FOX -- The Icon or .... ?

I have a few fox engines but I have never had much flying experience with them. I always thought that they were the ULTIMATE stunt engine; best of the best and all that jazz.

Now, I'm seeing all sorts of anti Fox posts.

Enlightenment PLEASE!

I have found that with proper break in and fuel, Fox motors can be used quite successfully with good reliablity. Where alot of the problems crop up is using synthetic fuels in these motors. All castor is the only way to go in the iron piston lapped versions. For what it's worth, I own about half a dozen old Fox motors that are 1950's vintage and they still work fine. Try to cut corners and you'll find yourself with a plethora of problems.

DAVE

The Fox .35 as stated when broke in and run with correct fuel will give good service. It lacks power of most in size but is lite. Quality contol in Fox is a joke. OS/Super Tigre/K&B/ Veco/ Enya/Johnson etc had them beat hands down. In olden days stunt flyers were like sheep and all used same equipment. Monkey see, monkey do. A couple of bad runs on a Fox and real trouble begins and gets worse in a hurry. With an LA .46 you run a tank of fuel on ground, next tank you fly a little rich. No way with a Fox.
I have a twenty year old Fox that is a good engine. My friend showed me some mods that he copied from a well known Fox expert. It Worked just fine and am quite happy with results. I have seen box stock Foxes do well also. They are not all created equal.
Dan

WHOA!

I guess quality control is (for me) the missing link. I have several Fox 35s and will have to run them all and ... just see.

Now, the $64 question:

I can't get a 4-2-4 break. I've tried taking off rich and wet lean but -- nada.

Also, I will be taking a Lil' Duper Zilch to Brodak's. I had planned on runinning a newly broken in 1952 Torpedo .29. But all suggestions will be appreciated.

I have Foxes, a .35 K & B Stallion, a plethora of McCoys (all types and sizes), Enyas, and an LA-40 -- all in pristine condition. Also, Fox .60 Eagles and a Hawk in case I purchase a "larger" ARF.

Comments, please. THANKS

>I can't get a 4-2-4 break. I've tried taking off rich and
>wet lean but -- nada.

There was a post on another BBS recently. Apparently, one important factor in getting a good 4-2 breaking run is 25-29% oil (preferrably all castor) in the fuel.

THe quality control on the new Fox 35 stunts is far better than it was back in the 70's and 80's. While the Vietnam war was going on QC was a joke, Fox made most of his money then turning out triggers for bombs.

John, I think your impression of the FOX probably comes from us older guys who were broken in on them in the 50's. We used to say that you don't break in a Fox, it breakes you in or you kill it. But we all learned how to make them work well cause it's all we had. And if you don't have experience or get help with FOX engines you'll surely kill them. Having said that, there is no contest comparing a FOX 35 to an OS LA25 when it comes to initial operation and power/cu in. OS wins. Unless you want the nostalgia factor, go with a modern engine.

I've been running / flying Fox 35s since 1952, have NEVER had a problem, still use the grand ole Fox Super Fuel, Champion VG-2 glow plugs, they just keep 4-2-4 chugging along !!!

As per the Champion VG-2 glo plugs, the late great Geo. Aldrich told me they were the best, and I believe it, just wish they were still made today.

Ken Wilson
Evansville, IN

I know this is hollowed ground but, I always thought Fox 35's suck and I still do. I got my first one when I was around 12,(getting hard to remember). I thought it was a piece of ##### then and I haven't changed my mind one bit. I have seen only one Fox that I liked and that was a Fox with an ABC piston liner combo down in Fountain Valley, CA that rocked. The rest in my opinion, can be used for a combination Fox 15\35 hurl contest. The 35 for guys with stronger arms.

Ya just gotta be smarter n what ya messin with.... :@

Hi John,

It does seem that people either hate or love the old Fox 35. Run properly, it is a great stunt engine. It does have it's limitations, though. Bigiron (Marvin D.) uses them in his Novi 4 with success. So do a lot of others. I have never had a problem with any of the Fox engines that were designed for stunt.

A hot plug, proper break in, and correct oil content are major factors. I am very suspect that many of those that do not like the Fox 35 really didn't do the proper things to start with. Of course a lot of newcomers do not want a 4-2 run. And that's ok. But I have never failed to get a Fox 35, 19, or 25 (all of them old models with 3 bolt back plates) to do a great 4-2.

I have run the McCoy Red Heads, Veco 35 Stunt, Enya, OS 35S, and about all the other "vintage" engines. Power might be a *little* better in different makes, but all are heavier, and if the plane is a good size for the Fox 35, it is all that's needed. I like them all, and the OS 35S is probably the best "overall". Having said that, I have put ST 46s in place of a Fox 35 in planes that were decidely obese!

What is your set up? I am curious as to why you cannot get a 4-2 break. (??)

Big Bear <><
Character: It's what you do when no one else is watching.

>I have a few fox engines but I have never had much flying
>experience with them. I always thought that they were the
>ULTIMATE stunt engine; best of the best and all that jazz.
>
>Now, I'm seeing all sorts of anti Fox posts.

If you are referring to anything I said, anti-Fox is a little strong. They have their good point and bad points, but, for all intents and purposes, they have been completely passed by for any practical application by other engines. At least if you don't modify them with the abundant aftermarket parts. The aftermarket parts make it work a lot better in most cases but then you are talking about a $200 engine, and you can certainly get much better engines for $200. In fact you can get 3 MUCH BETTER engines (i.e. Magnum 36, 40LA) for about the same money

The Fox runs today as well as it ever did, and better if you trick it out. It's close to *60 years old* and has hardly changed since it was introduces But the standard for engine performance is relative, and world has moved on.

And, Foxes never worked worth a poop on profiles. The burp is one aspect of it. It's a fundamental design flaw, the true nature of which was discovered by Frank Williams about 10 years ago, and it's relatively easy to fix. The vibration is another aspect of it, and that is best fixed by a Randy hi-zoot crankshaft and the ABC cylinder/piston assy. So, you can make it work respectably well for the cost of a spruce stick (10 cents), and $115 of aftermarket parts. Or, you can go plunk down $74 (or whatever) for a 40LA or a 20FP, get more performance, with no need for trick fuel, and no modifications. For me, it's not a very hard decision.

Brett

If your a sport flyer such as myself a ole Fox should work fine. I do not care much about the competition aspect. I have lots of Foxes and lots of the OS 40LA. Fox is still my favorite engine. Even on the profiles. One is with the ABC, Hizoot crank, and hemi-head. Great engine. The rest are stock. Some burp some don't. My OS 40s are fine for me also, but I have trouble getting them to fly at the speeds like with the 35 ounce profiles. (help appreciated here) I know that everyone (almost) does not like the ole Fox, but they do work. Check with Bigiron about your Fox engines,he is also a die hard like me.
Lee TGD (got on flack jacket)

> Fox is still my
>favorite engine. Even on the profiles.

I never said anyone shouldn't like them. Like is subjective, and I can't address this. Objectively, they aren't even good sport motors, and I see people thrash away for hours trying to get them to run properly, failing, and then come off the circle proclaiming how wonderful they are.

Far be it for me to interfere with anyone's enjoyment, or be critical of anyone. But there is NO WAY, if asked, I am going to recommend that someone get a Fox for sport flying. I would consider that irresponsible when far better alternatives are available. I'm sure that people will take that as a personal insult, but it's not.

> One is with the ABC,
>Hizoot crank, and hemi-head. Great engine. The rest are
>stock. Some burp some don't. My OS 40s are fine for me also,
>but I have trouble getting them to fly at the speeds like
>with the 35 ounce profiles. (help appreciated here)

The crux of the problem with 40's on "35-sized" profile kits (which I have seen 1000 times, too) is that a 40 is FANTASTICALLY too much power for the airplane. A 20/25FP will fly a model like a Skyray much better (objectively) than a Fox because it has far more effective power. And, it will running in a "happy" place in it's powerband. A 40FP is far beyond the capability of most people to control in these airplane because you have to try to run it at 25% and it keeps wanting to run at 75%.

The other classic problem with 40's on "35-sized" profiles is that a lot of people try to use the wrong propellor, and/or try to treat them like they were bored-out Foxes. A 10-6/40FP on a Twister, in general, WILL NOT WORK. It will wind up "running away" (that is to say, running as intended) and when you have 3x the power you actually need, and get it, you end up going way way way too fast. You need to run a lower-pitched prop, 4", and then get the engine detuned enough that you can run it at a happy spot. Even then, it probably won't work because you are still overpowering the airplane. A 40LA is a much milder/lower performance motor that will likely be a much better match for the airplane.

A third problem stems from the first two. In a vain attempt to get a "stunt run" (i.e. 4-2 break, emulate the performance of a 60 year old motor, in a manner that was essentially abandoned for competitive stunt about 20 years ago)from these engines, they start trying to "fix" them by carving on them with Dremel tools/hand axes etc. This is a dead waste of time and energy.

Brett

Thanks Brett, I run a 11/4 on the OS 49 with an extra head gasket. I can, somedays, get a 5 to 5.2 second lap time which is fine for me. I was told to perhaps drop the venture size a bit. Not done that as of yet. Appreciate your candid replies.
Lee TGD

What take off NV setting is correct for a Fox Stunt .35: Rich, wet lean, lean?

By the way, When I get back from Brodak's I'm going to run all my Foxes, pick out one or two best and Ebay the rest.

John, what works best for me is rich, turn the plane up and see if it breaks in a 2 stroke sound. If not lean it a little more until it does. It should change as you move the plane from vertical to horizontal. This will vary depending on tank location. I run clunk tanks mainly now so this is not quite the same as a metal uniflow may react. I usually get good breaks will all of the Foxes I have in use now. I also use APC 10/5 props. Works for me.
Lee TGD

>What take off NV setting is correct for a Fox Stunt .35:
>Rich, wet lean, lean?

Depends on the prop and the airplane, but usually, with a 10-6 in something like a Nobler, probably just barely into a constant 2-stroke with occasional blips of 4. When it takes off it should back off into a fast 4-stroke and then click into a 2 about on the top half of round loops. But, adjust it for whatever it needs for the right speed.

Brett

>Thanks Brett, I run a 11/4 on the OS 49 with an extra head
>gasket. I can, somedays, get a 5 to 5.2 second lap time
>which is fine for me. I was told to perhaps drop the venture
>size a bit. Not done that as of yet. Appreciate your candid
>replies.

Try an air filter with a fine element, that usually knocks it down a bit. Which OS40?

Brett

Brett
I don't know how long you have been in C/L,
but Iam willing to bet not very long. I have
been in it a long time! My dad gave me my
first C/L when I was 9 years old. That was
back in 1954. The first engine was a 19 cub.
It was OK but it did not have alot of power.
As the years moved on I got hold of some Fox
engines,and as long as they were broken in
right and used all caster oil in them they
never let me down, but I did find an engine
that out ran a fox hands down in stunt.It
was the McCoy Red Head .35.They had the best
4-2-4 brake of any engine ever made! I still
have these engines till this day and alot more.
So to make a long story short,if you brake in
an engine the right way and use the right fuel.
Most all engines will last a long time. I will
keep my head down and wait for incomeing on this
on .
Hank

Hank:

Yes - Brett and the guys he hangs out with hardly know which way to grab the handle!

>I don't know how long you have been in C/L,
>but Iam willing to bet not very long.

How much?

Brett

> How much?
===============
Same here. What's the bet?

Mike Keville
Aero Images

>As the years moved on I got hold of some Fox
>engines,and as long as they were broken in
>right and used all caster oil in them they
>never let me down, but I did find an engine
>that out ran a fox hands down in stunt.It
>was the McCoy Red Head .35.They had the best
>4-2-4 brake of any engine ever made! I still
>have these engines till this day and alot more.
>So to make a long story short,if you brake in
>an engine the right way and use the right fuel.
>Most all engines will last a long time. I will
>keep my head down and wait for incomeing on this
>on .

Durability has been more than acceptable with the Fox**, ***, providing you use the right fuel. That has never been a point of contention. I have Foxes that have had 30-40 gallons of fuel run through them*, and they still run pretty close to the same as they did when first broken in.

The fact that the fuel can be essentially "unobtainium" from local hobby shops IS an important reason to recommend other, better engines.

Brett

*p.s. oops, shouldn't have let the cat out of the bag on my 35 years of C/L experience (about 10 years of which were almost exclusively Fox 35), before I got the money from the bet....

**p.p.s. except for the crankshaft, of course, which is rather famous for breaking at inopportune moments....

***p.p.p.s and the conrod wearing out due to excess front-to-back motion from slop (discovered by Marvin Denny and fixed by stuffer backplate mod).

Brett
Holly**** Iam not trying to be a smart****.
If someone wants some advice on geting an
old fox running right for (OTS) why not help
them? I know that the engines we have today
are far better then we had back 20 or 40 years
ago. But he wanted to know how to make his fox
run better, and I know it can be done! I did not
mean any disrespect to you or any one.If I came
off looking that way Iam sorry
Hank

>Brett
>Holly**** Iam not trying to be a smart****.
>If someone wants some advice on geting an
>old fox running right for (OTS) why not help
>them? I know that the engines we have today
>are far better then we had back 20 or 40 years
>ago. But he wanted to know how to make his fox
>run better, and I know it can be done! I did not
>mean any disrespect to you or any one.If I came
>off looking that way Iam sorry.

No problem, I wasn't offended; in fact, I thought it was amusing on some level.

But, I and many of us here have literally thousands of flight with the Fox, and it's not exactly a new topic. We have gone over the important aspects of helping the Fox run as well as possible, time after time. And, making it run better wasn't the question, the question was why doesn't everybody (anybody) use Foxes amy more. Even the last of the die-hards in classic, Don McClave, for example,
(who knows more about how to run Foxes than anyone aside from maybe Bob Gieseke) are now dropping it for what Don calls a "Sizemore Fox", otherwise known as a 40LA.

Point being, we are not coming up with this stuff off the tops of our heads, we have learned this over many. many decades of experience with the Fox, and, just as importantly, almost every other motor that has been used in stunt. We have the necessary experience to at least be allowed an opinion on what it will do, and what it will not do, well.

For completeness, things to do to a Fox, in order of preference, to make it run better in this application (29% castor assumed, correct break-in assumed):

Bypass stuffer mod (~free, fixes "burp/quit")
ST51 spraybar (~$20, fixes needle leaks/inconsistency, breakage of stock needle)
Randy hi-zoot crank ($50, greatly reduces vibration, overcomes breakage problem with stock crank)
15% nitro fuel (delta = $2.00 a gallon, significant power improvement)
ABC cylinder/piston ($65, reduces vibration, relieves fuel sensivity)
Stuffer backplate ($???, reduced rod wear)
Trick head (Muggleton Stage III-IV or Randy~$25, smoother power delivery)

I would point out that most of these things were discovered/invented by people who post here - Frank Williams (bypass stuffer mod), Randy Smith (trick crank), Marvin Denny (stuffer backplate), and another frequent poster, Larry Foster, is *the* guy who builds trick Foxes to as near as possible to modern standards and knows as much about the topic as anyone alive.

Brett

Hi Brett,

Only change to your line up of fixes that I would add is to use one of Randy Smith's Fox 35 size PA NVA instead of the ST. Eliminates any chance of air leakage and any chance of the needle loosening up due to the vibration of the Fox.

Big Bear <><
Character: It's what you do when no one else is watching.

>Hi Brett,
>
>Only change to your line up of fixes that I would add is to
>use one of Randy Smith's Fox 35 size PA NVA instead of the
>ST. Eliminates any chance of air leakage and any chance of
>the needle loosening up due to the vibration of the Fox.

I was unaware of the existence of such a thing. I'm sure it will work, and if you don't have to search around for a few washers to center it up on the venturi, that will make it better than the ST51 needle.

To be honest, if you do everything else, and luck out, the Fox needle will work acceptably well. The trick is to get a half dozen of them, and find the one that works the best. It matters A LOT where the flat spot is when it's adjusted properly. I forget the correct orientation, but it has to do with the where the flat spot lines up with the holes I want to say it works best when the flat is perpendicular to the holes, but I wouldn't put any money on it. If you get the right one, it will be reasonably linear over the 3 clicks it will run. Near as I can tell the orientation of the threads, and the flat spot, are just random, as is the correct position of the needle. I can't tell you how many hours it took to figure that one out. Then, I put in an OS35s spraybar/needle, and forgot about it until about a year ago when somebody asked about it.

Brett

>>Hi Brett,
>>
>>Only change to your line up of fixes that I would add is to
>>use one of Randy Smith's Fox 35 size PA NVA instead of the
>>ST. Eliminates any chance of air leakage and any chance of
>>the needle loosening up due to the vibration of the Fox.
>
> I was unaware of the existence of such a thing. I'm
>sure it will work, and if you don't have to search around
>for a few washers to center it up on the venturi, that will
>make it better than the ST51 needle.
>
> To be honest, if you do everything else, and luck out,
>the Fox needle will work acceptably well. The trick is to
>get a half dozen of them, and find the one that works the
>best. It matters A LOT where the flat spot is when it's
>adjusted properly. I forget the correct orientation, but it
>has to do with the where the flat spot lines up with the
>holes I want to say it works best when the flat is
>perpendicular to the holes, but I wouldn't put any money on
>it. If you get the right one, it will be reasonably linear
>over the 3 clicks it will run. Near as I can tell the
>orientation of the threads, and the flat spot, are just
>random, as is the correct position of the needle. I can't
>tell you how many hours it took to figure that one out.
>Then, I put in an OS35s spraybar/needle, and forgot about it
>until about a year ago when somebody asked about it.
>
> Brett


Hi Brett,

Randy's spray bar is machined to the same size as the stock Fox, it uses his PA needle and the nylon seal collett. It's a drop in replacement.

Didn't have a clue as to the "fix" you found as to the flat spot on the Fox needle. Didn't take too many gallons of fuel on that one, did it?? LOL!!

Big Bear <><
Character: It's what you do when no one else is watching.

>Didn't have a clue as to the "fix" you found as to the flat
>spot on the Fox needle. Didn't take too many gallons of
>fuel on that one, did it?? LOL!!

That one was about 40 gallons into the program.

I actually kind of like having "clicker" needles, as opposed to the friction/"stepless" type (like the ST). Keeps you from tricking yourself into making too small adjustments.

Brett

The Fox 35 has most certainly NEVER been the ultimate stunt engine (if such a thing even exists).
Bret's statements about the Fox are probably a little kinder toward the Fox than I would be, but essentially I agree with what he has said.
I would simply add that if you have a Fox 35 and wish to use it, do so, it can be made to work.
If you're going to buy something new, specifically for stunt for heavens sake spend your money on a modern stunt engine that doesn't have all the problems and doesn't have to be "played with" forever to get good consistent runs. Stick with Brett's suggestions for the smaller profiles like the Skyray etc.
Personally I would reccommend a larger airplane and a good 40-46 like the OS LA's and the Brodak profile Cardinal (the kit is an excellent flying stunter, can't speak for the ARF). I say this because I sincerely believe them to be easier to fly, especially under less than ideal conditions, and that's exactly what an intermediate level flyer needs.
For built up fuselage airplanes in the 500-600 Sq in class, a real stunt motor like the Aerotiger 36, Magnum 36, RO Jett 40, or PA (light) 40 is the ticket. Yes they are more expensive but you'll get much more flying done and they'll last "forever". If you put all the trick stuff on a Fox it still won't be as good (it will work OK), and you'll have spent as much money as for the motors mentioned. I would add the Rustler 40 and Double Star 40 to the list, not that they are quit equals (IMHO). If you need more testimony to this look at what most expert level "winners" are flying. They don't use this stuff because they just want to spend extra money. They use it because it works, and allows them to concentrate more on flying.
'Nuff Said.

This has been an excellent thread. I ran a old Fox in my old time Reinhart International because in the original Air Trails construction article, there was a Fox. I also have an ABC Fox which I had in a very light (for me) Oriental and was my best flying plane to that time. I have been using FP20's in a SkyRay I built for my sweetheart (we plan to be married August 19) and in a Combat Streak and in a FoamRay (SkyRay with Cartier foam wing) and I am very happy with them all. I totally agree with Brett's comments on FP40's, I found I had no application for them, although they seem to have acquired a cult following, I dumped them on eBay. I am preparing yet another Oriental for a Magnum 36 (maybe too much engine) and my Already Crashed and Repaired Cardinal has a 46LA with which I am very, very happy. Anyway, I did enjoy my Foxes/Orientals since 1972 but it is now 2006 and Hooray Beer!

In answer to your question Bret, I have an OS 40LA on a Banshee. I tried 10/6 last week and seemed to work fairly well. I will go back to the 11/4 and see what happens to the times. Clunk tank w/uniflow.
Lee TGD

THANKS everyone, I have never received so much usable information ... EVER!

I have two new LA-40s, one has an R/C carburator. Where's the best place to get a c/l venturi?

Should I keep the K&B Stallion .40 for "profile" use?

Are good running Enyas worth converting to C/L?

I have not yet drilled the motor mounts on my Lil' Duper Zilch. I had planned to use a Torpedo .29 but I'm game for suggestions.

Hi John,
You can find a venturi here: http://www.clstunt.com/products.htm and also an NVA for it.

Cheers,
Ken

BTW: Didn't Kenny Stevens win Advanced at the Nats a few years ago with a FOX 35????

Wes:

>BTW: Didn't Kenny Stevens win Advanced at the Nats a few
>years ago with a FOX 35????

Yes. It wasn't in a profile.

Brett

>In answer to your question Bret, I have an OS 40LA on a
>Banshee. I tried 10/6 last week and seemed to work fairly
>well. I will go back to the 11/4 and see what happens to the
>times. Clunk tank w/uniflow.

For a LA, try that, and an 11-5. The LA is a very different animal from the FP, and generally better suited for stunt. As I suspect you found, the LA is not too happy chugging along with a 10-6 - that's why it sometimes goes too fast. You have to dial it down so much that it won't stay there, at least, not every time.

Assuming a *stock* motor, of course. Aftermarket jobs, well, you are on your own. I have seen some perfectly good, stock, 40 and 46LAs that have been "improved" to the point that they put out the same or less power than a Fox 35. I won't dismiss the possibility that someone out there knows how to actually improve the motor, but I sure haven't seen any.

Brett

After a forty year lay off from CL I bought seven Fox 35s through Ebay to power my fleet. I hadn't talked to anybody about flying, I just wanted to fly CL again . All the engines were used but all were in good condition except for one with a hole in the piston.(The seller said it just had a little play use.) I started my fleet with an ARF Flite Streak and a Sky Ray. Before I had a chance to fly them I went to the Fall Follies in Salem and watch a few fair hands fly. Paul Walker, Howard Rush, Dan Rutherford. Scott Riese, etc.(Sorry if I left "you" out) I had no idea who these people were but they sure did fly well and nobody was using a Fox 35. A guy my age who was flying an Oriental with oriental writing on the wings said to me after I told him I was getting back into CL with Fox 35s "Do yourself a favor and buy an OS 40 LA or some other modern engine." What did he know? As it turns out Mike knows quite a lot. When I first started a Fox 35 on the Sky Ray I thought the lenses in my glasses must have fallen out. There were two, no, three engines on the nose of the Ray. All but one of my six engines produced the same result. The one that didn't shake the nose off the plane had the "burp". I have seen five profile planes at Delta Park with Fox 35s do the figure 9 when the engine "burp" quit on an outside loop. How is a newbe or a retread going to learn anything except flying level and an inside loop using a Fox 35? "Do yourself a favor and buy a OS 40 LA." Best CL advise ever given to me.

Later
Richard

Well, John, if you have your sights set on winning the Walker Trophy, then a Fox 35 sure ain't going to get you there. But if you have them (like you say you do) and just enjoy flying C/L Stunt, then Iwould keep one just because. A whole lot of guys here give exactly the correct advice but not everyone can be as successfukl as Paul Walker, nor do they have the money to buy up engines.

I have about every one of the popular new stnt engines, and have used them in various situations. If you want a dead solid top level CLPA engine that gives no hassles, then get an appropriate sized PA engine w/pipe for the plane you want to build. And set it up and run it EXACTLY like Randy Smith says. That is the most reliable set up I have seen everywhere I have been. Do disrespect meant to anyone. Problem is, way too many people try to reinvent the wheel. Some can, but most fail. A good complete PA system can be had used for a little over $300 usually, depending on engine size. The correct Bolly prop will be $30-$40 new and get at least one back up.

A close inspection of your goals in CLPA are in order to see what "engine systems" you really need.

I will definitely agree that an OS 25LA set in a wet 2 stroke with a 4 pitch prop, right out of the box, will "usually" be a great improvement over a Fox 35 on a Ringmaster.

The new engines are super easy to use (try Brett's OS 20FP set up) and the method of running them has vastly changed since the early '90s like Brett said.

Big Bear <><
Character: It's what you do when no one else is watching.

I think that there should be recognition that Foxes come with at least 2 sleeve configurations. There is the Fox 35 sleeve with the small intake and exhaust ports and the one with the much larger intake and exhaust ports. My Fox's with the small ports seems to have a propensity to quit when the plane is upwind and at about 45 degrees or more. They are so bad I take my dremel and open up the ports to the larger size. I have visited the factory and asked about the difference and was told that the ports were cut smaller by mistake. Unfortionately the smaller ports seem to make the engine run hotter, which is why IMHO the engine quits at the worst time and place.

I figured out why you guys are having so many problems with your Fox engines... too much science and TLC!

Break In - Two 4 oz. tanks of what ever fuel you have around and then run out both tanks on a test stand (AKA a 2X4 clamped to the porch steps). Bolt into your favorite Ringmaster. Take it to the local ball diamond and be sure to launch on the dusty part of the infield. It's a scientific fact that the best "lapping compound" can be found on a ball diamond. The ingestion of these fine particulates will accelerate the break-in producing a Fox .35 with the precise tolerances for maximum performance. Hey... it worked when we were kids!

Hi John:
Rather than go into all the advantages/disadvantages or suggesting that most would be better off with their fox 35's on ebay or in their tackle box, I would say the Fox 35, old or new, is a very good to great stunt engine IF you are one of the relative handful of experts familiar with Fox 35 engines.
Otherwise, unless you want to spend significant dollars for Fox 35 tuning, some or which involves using nothing from the original engine except the crankcase there is just no reason whatsoever to use them.
For example, for the price of one of the best tuned fox 35's you can buy two Brodak 40's, equal to greater power, only an ounce or less heavier, close to idiot proof.
For the price of an untuned Fox 35 you can get an OS LA 40. No long break in, no wasted two gallons of fuel, no need for high castor specialized fuel, lots more horsepower, no burp on profiles, idiot proof. The fox 35, even if well broken in, needle valve replaced, etc. in still will likely provide significant user challenges and frustrations-Ok I suppose if you have a high threshold for frustration.
OOOPS-said I would not go into advantages and disadvantages.
Sorta like comparing a 1948 Studebaker to a new Chevy Impala. Neither are state of the art but one functions well, the other is awkward and outdated. The choice is obvious for the user given equal pricing.

Jim P tell us what you really think of the Fox 35!!

>Jim P tell us what you really think of the Fox 35!!
Hothandle
Well, I guess I done did. Great in the 50's, OK for a few today.
Jim

>Sorta like comparing a 1948 Studebaker to a new Chevy
>Impala. Neither are state of the art but one functions well,
>the other is awkward and outdated. The choice is obvious for
>the user given equal pricing.

One is still around after 58 years and the other doesn't have a prayer of lasting that long.

We are currently flying three Fox 35's. All are profile mounted. All are running outboard Hayes tanks. One has had at least a 55 gallon drum of fuel run through it while the other 2 have had about 2 gallons. One of the newer motors is running without a muffler and the other two on muffler pressure. All start with 2 or 3 flips and 4-2-4 all day. None of them die on outsides. Granted they are not the most powerful, but they are not the devil that folks make them out to be, and they sure sound sweet when they're breaking.
Now, in case Zuriel(Z2) reads this and thinks I'm full of it, because he landed one of my Fox 35's inverted from an outside flameout a few weeks ago, it was the plug. It did the same thing to me the next afternoon. I changed the plug and it hasn't happened since.

What's the only thing uglier than a blue motor on an airplane?
A blue motor with a natural muffler.

Would people PLEASE quit buying the blue motor......you know it comes in natural?
Why in the world couldn't they make a matching muffler?

>One is still around after 58 years and the other doesn't have a prayer of lasting that long.

Me either.

>All start with 2 or 3 flips
Amazing! Must be different Fox 35's than the ones I see our locals flipping on until their arms are blue. When the circles are crowded and the air is nice, we should declare a "no fox" period so that folks can fly without wasting a lot of time.


>Would people PLEASE quit buying the blue motor......you know it comes in natural.
Yep, and they are cheaper too. If a guy works his tower discounts right and sells the RC carb and muffler, he should be able to get into an FP 40, stunt ready with venturi, tongue muffler, and ST needle valve assemby for well under $40, $5 or so higher for the LA 46 natural.
Now how much was that Fox 35 stocker again(not counting the $25 of break in fuel)?
Jim
Opinions are like rectal orifices-everybody has one.

>All start with 2 or 3 flips
Amazing! Must be different Fox 35's than the ones I see our locals flipping on until their arms are blue. When the circles are crowded and the air is nice, we should declare a "no fox" period so that folks can fly without wasting a lot of time.

Your locals should come to an engine clinic so they can tell whether an engine is wet or dry. Most any engine that has good compression can be made ready to start in one or to flips - and that's not an opinion - it's a fact.

>Your locals should come to an engine clinic so they can tell whether an engine is wet or dry

I can usually get them started for folks after clearing the flood, going through the backward runs, etc.
Or conversely, priming on top of the piston(in cold weather). They case load with choking in colder weather before getting enough on top of the piston to fire.
And then there are those that are worn out or overcooked that just will not start until they cool down.
Easy way to avoid all this-get another engine.
Jim

I actually still have my Fox 35 from my tender tender youth,(okay not so tender) and I do plan to send it Frank Bowman to fix it up. But, not because I have anything serious planned for it that's for sure. I can see how if you wanted to do a classic ship and wanted to remain true to the spirit of the thing right down to the authentic suffering with the Fox 35, then rock and roll. But in this day and age of more than decent engines-why?

I guess the Fox 35 is a sore spot with me because I abandoned a fantastic running Enya 5224 with the black venturi for the Fox because all of the East Coast stars back when were running Fox's and they wouldn't speak to me until I got one.

Granted, the fact that I can take a Saito 72 out of the box and make it run pattern after pattern without a hick-up can possibly be attributed to the "hands on experience" I gained in my youth with the "character building" Fox 35.

Back around 1977, I decided to take up flying stunt. I bought four Fox 35's on sale for $12.95 each. I did replace the Fox NVA with an ST NVA. All four ran the same and ran to suit me at the time. I had no problem that I recall with them and they served me reliably. I still have two of them (one hauling a trainer around)and may fly one again someday. So I think Fox 35's are good. However, If a new CL flier asked me what to buy, I would say LA 40. As said, easier to get the performance.

One thing to remember. A Fox 35 must be compared to other 6 oz engines, not other 35's 36's and 40's. The OS LA 25 is one, but even the OS LA 15 is 5.5 oz. Of Course, you can't beat an OS MaxS 35 @6.5 oz.
Another thing, it run's better upright or inverted. I prefer McCoy's for side mount.
One last kudo for the Fox. There are left hand cranks for the Fox. I bought two many years ago. The left hand crank is a necessity for aircraft like the All American Sr.
Happy Landings

>The left hand crank is a
>necessity for aircraft like the All American Sr.

Or you could build it to fly clockwise..

At Indy, the offenhouser was the engine of choice for way too long. Then came the v8s. Same thing with the Fox. It has had its time. Still a good engine, just no longer a great engine. I have several and the ones I fly with are ALL L&J conversions. So no longer really a Fox. As to the "burp", I learned from AL Lennon in Pocatello, Idaho in 1971 how to eliminate it with a popsicle stick in the fuel port next to the liner. It was no big secret, just what "they" did. With no PAMPA newsltter, no internet, things like this took forever it seemed to get out.

After giving it a long memory chase, my brain came up with the fact that have used exactly 2 Fox .35 stunt enignes, from the box, ever!! Seems I started out in stunt with a Barnstormer and a McCoy .29 Sportman. Then on to O&R (ugh, ugh), Forster (ugh),Super Tigres, (rah, rah,, K&B green heads (wow) (NO K&B Stallions-bad, cheap engine), OS Max, and four L&J mods to Fox, which makes them no longer a Fox. OS engines so far have been the best in my collection of power plants. Have not tried my Saitos yet. So, no Foxes

You answered a BUNCH of my next questions ... so

Please check out my next post regarding suggestions for repowering my Ringmaster which I WILL be taking to Brodaks (With a highly reinforced left wing). I will put the LA-.40 in an ARF (Probably an Oriental) as soon as I get there on Sunday. The Ring will do service as a practise platform and a "Profile" entrant.

Hmmm. I actually have a Fox Stunt, NIB, which I won (at a combat contest!)... Someday I'll bring it out and break it in, and put it on a Twister.

The only Fox Stunt I've actually had that's been run was from back in the day when "Super Slow Combat" mean Fox Stunts, rather than a speed limit (like today). Talk about S-L-O-W! I bought a used one from Indy RC, screwed a pressure tap in the venturi, and used a remote needle and bladder. Worked OK, but vibrated like the dickens. Turned out the best prop to use was a Taipan 8x6 - it outran most of the other Foxes that turned up other than Bud Bodzioch's (he's got a real, honest to goodness 80 mph one, and he's the one who pointed me towards the 8x6 props..). The Fox Stunt might make a fairly decent Stunt engine, but I must say, it sucked as a Combat engine. Not much power, and hot restarting wasn't at all easy.

Anyhow.. just curious. Back in the day of the Flite Streak and the Ringmaster, did all those teenage sport fliers really care about this 4-2 break 5-second-lap stuff, or did they simply fly the darn things around as fast as possible?

You are right, we didn't care about the 2-4-2 break. We did know about lean runs cooking the piston/sleeve though (from hard learned experience). We did think faster was always better. Good post.

Truthfully I've recently gone back to running my foxes a lot faster than the 5.0 sec lap time, slow 4-2-4 type of run and I haven't had any problems with the engines cooking themselves or vibrating, etc.

I am probably well within the operation limits of the fox and the planes actually fly better - stronger pull, no burps, etc. They're not that hard to start either - once set correctly.

When I get one from the bay I usually have to fiddle with it a little bit to get them set correctly. I then run for about 5-6 tanks through them before I start flying. Of course this is true of all the engines I get used from the bay, etc.

I'm not an expert and will never be an expert. but for the 20 to 25 bucks I'm spending on the old fox 35's I am getting an awful lot of fun for my money. I've had people give them to me for nothing sometimes.


Now my planes aren't super light but they are not that heavy either so that gives some latitude in engine performance

A Fox guy with a "McCoy 40" handle?

I and all my friends had McCoys in the 50's. I flew my first Fox last year at Brodaks in a Bi-Slob. I totalled the Bi-Slob and will replace the wings "sometime" this summer. I just couldn't get used to the underpowered feel of the Bi-Slob/Fox set up. When the Bi-Slob is back in the circle I will probably have a hot .40 or a good .60 for power ... hovering does not appeal to me.

I have both engines.

as well as mccoy35's, k&b's, os, etc.

Power is very definitely necessary - hence my bump in speed and performance on the foxes

It's not so much that they're hard to start, it's just that they're hard to start in the middle of a match after you've stuffed it in the dirt and are trying to get back up again as quickly as possible. I know the Foxberg Racing people know how to do it, for me it was iffy. Once in the air, as long as you went up a little rich, they ran OK, but I still have a scar on the inside of my left wrist from when it quit on me directly overhead in a match, and I put my hand up to protect my face. Got the propshaft square on the wrist. (Center Marshal came over, took a look to make sure there wasn't blood spurting everywhere, and said "OK, continue!".)

i got my first fox 35 in 52 or 53...mine just wouldnt break in....one of those that ran the conrod into the back cover...it ran good through most of the flight then it would start boggin down and sag untill it landed still running and just smokin hot!!!...this after a few months flying...my dad and i took it duke when he was on varna(north hollywood) he gave me a nice one that always ran good...i havent been around in forty five years ..lots of things happened since then...but in th 50s all those guys that won with foxes either knew how to fix them...had fox do it...or got really lucky when they got a good one out of the box...fox had a good engine..but poor quality control...it got really bad when fox moved to arkansas ..."THE"icon?....not back then... ...jim

Here are two questions which we can discuss indefinately without ever knowing the truth. Here are my guesses, which are just that.

Of all the first through third place airplanes in all the stunt contests flown in the USA from 1948 to the present, what percentage were powered by Fox stunt 35's? My guess -- 60%

Which engine is in second place? My guess -- ST 46

Fox Stunt .35s have won more contests then all of the rest combined.......and are still as capable when installed in the proper sized and weight plane.....Maybe we can even run them on a pipe... ;-)

Some time ago, early 70's I think. I bought a new Fox Stunt 35 from A.H.C., broke it in per instructions and mounted it on a re-built Sterling Mustang to see what all the hype was about. It replaced a well worn Fox Rocket red head. I never could get used to the 4 2 4 break and would always try to lean it for more power, even the worn out Rocket seemed to out power the new stunt engine. I eventually gave up on the Fox Stunt and it sits today in the original box, I have no use for it, just my opinion here. I Thank You.

I have never been a fan of the Fox 35 Stunt, and would never put one in any of my ships (personal choice, so keep the safeties latched on your flame throwers ) As Brett points out, there are many “fixes” available for this engine that cost a considerable amount of money. I have wondered for some time now, since the Fox 35 has a large following, and Fox still produces this antique, why hasn’t Fox implemented some of the known “fixes” and improvements so many people advocate?

Pete

I am not getting into the debate about OS vs. Fox, but the one thing I do like is that Fox is still making engines here in the US, that right there is reason enough to own a Fox engine even if all you do is run it on a test stand.

< I have wondered for some time now, since the Fox 35 has a large following, and Fox still produces this antique, why hasn’t Fox implemented some of the known “fixes” and improvements so many people advocate? >

Perhaps its because Duke himself, and the folks at Fox that came after, knew that when used as intended, that the Stunt .35 was and is perfectly capable.....other than taking apart and carefully deburring, the only thing that I consider worth doing is to install a stuffer back plate and do a carefull break in using the fuel and procedures that Duke laid out so many years ago, and if I need more power, I simply bolt in a Fox .40......(non schnurel) version and if I don,t care about a 4-2 break, any of the new Fox engines are certainly capable........

Now that all that is said, I am certain that we could name any engine that we care to and say virtualy the same things about it..be it a model engine, car engine, motorcycle engine, and even full scale continental and lycomings.......kinda like the old Ford, Chevy, Dodge argument........they are all good and do their intended jobs very well...but for the sake of a good argument, I will stick with Fords, Foxes, and Franklins........ ;@

Mornin Phil;

I wasn't going to get into this, but what the hey.

"FOX ICON" I own a "FEW" Fox engines both old and new, not the least of which some are the venerabie .35 Stunt. Don't worry Mr. Lucky the safety is on. LOL My experiance with these engines (both stock and modified) is that if you follow the break in to the letter you will never have a problem.

I have never had one burn up,seize up or any other mishap that has been discribed over the years. Yes I agree they lack a little in the QC department, so I just do it myself,simple

I guess the bottom line here is that you either like them or you don't, if you don't just don't use them, if you do have fun.

For those of you that don't like them and are thinking about tossing them remember this: I HAVE A VERY LARGE BARREL THAT YOU CAN TOSS THEM IN< ANY CONDITION WELCOMED.

As a final remark Fox has been around a long time and it dosen't look like they are going anywhere in the near future. There is room in this HOBBY for everyone whether you are a Fox person or not. Just take what you have and go out and have FUUUUUUN!!!!!!

Avid FOX collector and CLPA enthusiast;

Bill Gruby [photo not recovered: sipcof.gif]

PS My Ringmaster still has an unmodified 1950 >29R Racing Special on it---FOX FOREVER

Lordy, lordy, lordy!

I can hardly believe that this old thread (07/2006) has lasted this long.

When I saw and heard my first Fox .35 the year was 1951 and I was 16 years old. The Fox was in a gorgeous Staggerwing Beech and the pilot was an expert. (I was impressed.)

The next time I saw someone flying a Fox powered airplane was at Brodak's 2005 Fly-In. (Again, I was impressed)

My point (or is it a question?):

To me, the nostalgia factor plays a huge part in my C/L hobby. I was a "McCoy man" as a kid and to this day. Are the boys who were "Fox flyers" ditto, ditto?

Is anyone out there who still flies an un-burped Fox/Ringmaster just because, just because?

John---Read post #69 and your question will be answered LOL

Bill Gruby [photo not recovered: sipcof.gif]

If you are a sport or mild stunt flyer, the Fox Stunt works just fine. You may be using Foxes on Ringmasters, Streaks, CG Busters/Shoestrings/Cosmic Winds, or perhaps Tomahawks, etc.

You are of course putting an engine that was state of the art in the 50s on a design that also is 50+ years old. If this makes you happy, then go for it. There is a lot of potential fun here.

If you want to move a bit forward, put the wooden stick in the bypass, and you probably will tone down, or even eliminate, the Dreaded Fox Burp. Or, if you want to move into a more modern era, simply use an OS 20 or 25 FP, and enjoy a smoother running experience.

I have quite a few Foxes, starting out with the 4 bolters with the 2 bolt backplate, all the way through the 50 Anniv (wow, an actual mount for a muffler...). Generally, they all are fast starters cold, and after sitting around for a while. As purely hot starters, such as in a Foxberg race, you need to know the particular engine you are using for any idiosyncratic restart needs.

A little off the subject, but I find that some of my best Fox Stunts are 29s, and not 35s. Probably just a random thing, but, does anyone else out there see this?

In over fifty years of modeling, and countles profiles flown with countless Fox Stunt .35s as well as McCoys, Vecos, K & Bs,Johnsons, OS Max, and all the rest, I have yet to experience the so called (burp)....mebbe I have been doing some thing wrong for fifty odd years... and if I was gonna move up, I would order me a new Fox .25 or a new Fox .40. or a new Fox .60....but like I said in an earlier post, if a Fox stunt .35 is broken in and ran as intended, it is as capable today as it was nearly sixty years ago when it was introduced and the only thing worth doing to it in my book, is to put a stuffer back plate on it.....There really is a reason that the Stunt .35 has won more contests then all the rest put togather and is still in production today.......

Now if Duke had just made an aluminum ringed piston for it.....

I have a VERY old Fox 35. I bought it back in 1951 I think.
I recently got re-interested in CL and sent it to Fox and had
a new sleeve and piston installed. I have ran it a couple of time
on a stand and it seems to run like new. I am putting it into
a scratch built Ringmaster and hoping for the best in my retro
CL experience.

[photo not recovered: 22080.jpg]

Attachment #1, (jpg file)

Woody: You have a pretty old one, dating back to the California Arnold & Fox days. The only older ones are with the two bolt backplate.

Currell

Currell;

You have a good memory that is indeed a 1951 Fox .35 Stunt all .35's prior to that one had 2 bolt backplates. Mine go back to 1949.

Woody go for it put that on your Ringmaster and just have fun like we used to. I just love to see those old Foxes reincarnated and used again.

I wonder if the newer engines will be around that long. Only time will tell?

PS after seeing your post I went back over mine, I have very large fingers and hit the 8 instead of the 9. I have yet to see the early Fox without the web myself. I use AMEE for any identification. Sorry to have misled you.

The very earliest 4 bolt head-two bolt backplate Fox doesn't have the boss between the case and the venturi. They are very rare, and the only reason I know about this is the Anderson Blue Book. I have never seen one.

Once again, as many have posted here, here is an engine that has undergone about a dozen or so crankcase updates, yet you still can interchange, up and down, the piston and sleeve assembly, and also the crank.

And a little bit more about the Dreaded Fox Burp. These are just opinions on my part...

1. Some of the folks who say their Fox Stunts are unaffected by this may not be paying the fullest of attention. It is there, but it has happened so often (and it is so brief, usually) that it goes unnoticed. Sort of like your thumb using the space bar on your keyboard, or your noticing your heartbeat. I probably have run about two dozen different Fox Stunts (29s and 35s) on a variety of profiles, and never have seen one that did not have a burp on outside maneuvers.

2. Go grab a few Foxes over the years, if you have them available. George Aldrich, either on Flightlines or on Isky's site, measured the bypass volume on a number Fox Stunts, with the earlier "sandcast" ones having the greater values. You can eyeball this, without going through the laborious measuring process such as GMA performed. I use Foxes a lot, from the early to the late ones, and cannot get a correlation between bypass volume and "burpability". Apparently, once the volume exceeds a certain volume, it is like an on/off switch. And the small volume ones (pretty much the latter engines) already have the switch on.

Currell