Fox 36 c/l slant plug model

I have a NIB Fox 36 slant plug engine plus a couple of good used examples. I have wondered if Fox put this engine out as a sport engine rather than for stunt which their 35 filled. Maybe it was supposed to cut into the market that the K&B Stallion was aiming at. It seems to have a higher compression ratio than the Stunt 35.

Does anybody know anything about this engine. I want to use this engine for OT stunt and would like to hear from anyone who's doing this?? Thanks, Brian

It's not as good a 4-2-4 running engine as the usual Fox Stunt .35, but it (and its companion 29) is a quite capable sport/stunt engines. True, they aren't used that much, and are overshadowed by their Fox Stunt cousin. One of the problems was their release date...rather after CL interest had peaked. So sales weren't particularly strong. And, they were competing with the Stunt, of course.

One of the best 4 cycle-2 cycle needles that I have ever created on a flight was for a couple of CL newbies (RC guys on a lark) a few years ago. They couldn't get their .36 (Shoestring, if memory serves) started, so I helped. Really a sweet run, much better than I gave myself on Fox Stunts or OS 35-Ss or whatever else I was running that afternoon. Every plane they brought out had this .36 engine, by the way.

So go for it.

More: The .36 has a little more power (more compression, and the timing is a little more agressive) vs. the Stunt .35. So, another thing you can play with is adding one or two head gaskets.

Want to give a Fox Stunt .35 an instant steriod boost (while screwing up its 4-2-4 characteristics)? Stick a .36 head on it. It's a two minute, perfect bolt on operation.

>More: The .36 has a little more power (more compression, and
>the timing is a little more agressive) vs. the Stunt .35.
>So, another thing you can play with is adding one or two
>head gaskets.
>
>Want to give a Fox Stunt .35 an instant steriod boost (while
>screwing up its 4-2-4 characteristics)? Stick a .36 head on
>it. It's a two minute, perfect bolt on operation.
>
>Currell

You can do the opposite with the 36, put the head from a 35 on it. Watch the fence, however. The fence on the 36 is taller and slightly more towards the center. This, more than anything, gave the 36 more of a power boost. Matter of fact, you can put the 36 piston in the 35 engine (keep the 35 sleeve) and change the head (because of the fence location) and keep the run and get more power. It forces you to raise the engine on the beams (or lower it if inverted) by about 1/8 of an inch to keep consistent upright and inverted runs. This is one oddity that I have never understood in that the only change you have made to the engine is in the piston.

It was a great slow combat engine. It also came along about the time that slow combat was being considered as becoming an official event, so there may be a connection. I have a couple and they are nice. Light, powerful, and consistent easy starters.

I have one and agree with Chuck, I like mine a lot.
I seem to remember that they came out at about the same time as the ST C35 which was much more powerful and so wiped out the fox for Combat..... I also have ST C35's and they are better than the Fox36 IMHO

These engines are typical Fox junk. The one you want is the ball bearing version. If you have the needle bearing version make sure the needles are not gooped up or you'll fry the crankshaft. I would suggest removing the needle bearing and replacing with a phospher bronze bushing. A good piston fit is rare in these engines. I happen to have a good one that was hand picked from the factory and, it still requires extra oil and a fat needle valve to keep from over heating. Get the liner properly fit and tapered and it will be 200% better. Some of the cranks were'nt heat treated right and are brittle. Try tighting the prop on real good and see if the prop shaft pops off. If you need to replace it, the needle bearing shaft is slightly bigger than the ball bearing shaft. Good luck finding one that's made right.
I would try to find a better engine.

Giffy

Giffy,

If I'm not mistaken, the Fox referenced by LU2 is what's now known as the .36 "Stunt". This engine had a plain bushing rather than either a ball or needle bearing. I hope that LU2 will correct me if I'm wrong. Here is a dim picture of one.

The 36 vibrated even worse than the 35, but did have a little more power. It was also a bit heavier than the 35, so I found little use for it. I hadn't thought much about it, but this might be a good engine for the ARF Nobler. The inverted engine should be less of a vibration problem than on a profile.

I do, however, have one that Aldrich reworked including a chrome sleeve. I haven't run it yet, but have high hopes for it.
Steve

LAST EDITED ON Nov-12-03 AT 06:16 PM (CST)
 
Hello All,

I am just getting back into C/L after 30 years. I got up in the attic a couple of weeks ago and pulled down 6 large shipping cartons of model airplanes, engines, and enough balsa and other other accessories to build a lot of planes. Out of a collection of about a hundred engines I specifically looked for the slant plug 36's and couldn't find any of the two I knew I had. I bought the first one to use for local club fun fly type events and slapped it on a Flite Streak turned out to be a nice combo and flew well first time. It seemed like that engine got better and better as time went on. Then one afternoon I was doing a wingover and smacked that sucker straight into the asphalt. I was looking into the sun as it came over the top, sneezed violently just at the wrong time and lost it. After sweeping away the litter and pulling the engine out of the pavement I decided I better get another engine. It was a warm day and the asphalt gave enough to leave a hole back to the crankcase. Tips of the yellow 9/6 plastic prop were sticking out of the hole and looked something like a crocus just coming out of the ground in the spring.
I went back to the hobby shop and bought another 36 built another streak and again was fairly happy with it. The crashed 36 although it was partly buried in the asphalt had no apparent damage to the crankcase and only a mild dent in the back plate, probably from the crank slamming into it the only apparent damage was to the prop nut, washers and the needle valve assembly. The intake was scratched up but not cracked. After the new streaks were built I cleaned up the front of the shaft, put a new nut and washer on it and tried running it on the test stand as it turned over and didn't seem to be binding. I opened the needle valve about 3 turns primed etc. flipped the prop and flipped the prop again and again. Put in a new glow plug flipped the prop and it started first try. It sounded great and ran through 10 ounces of fuel. I took the engine to the flying field and flew it on the new streak. Everyone commented on how well the new 36 was working. When I told them it was the old one they didn't believe it at first until I showed them the new one on the other streak. I explained that the previous incident with the engine wasn't a crash; it was a successful attempt to dynamically tune the engine. That engine still improved, as it got older. About a year later I managed to scrape up the head pretty bad and when removing it noticed the sleeve was rotated about 60 to 70 degrees clockwise in the crankcase. I don't know when it happened or how for that matter. I do know that after putting on the new head and putting the sleeve back where it belonged it didn't run as well, although it still ran pretty good. That was several moves ago that I last saw that engine. Although I don't want to dynamically tune another one I would like to try turning the sleeve again.

Giffy: Your opening sentence suggests that you cannot render an objective judgement re these engines.

Just a thought. Well, two actually. If you'r thinking of using your 30 year old balsa just check that it's not gone too brittle for practical use. You just might build a model that turns into the proverbial bag of balsa bits without even crashing.
And if tempted to use 30 year old yellow nylon props, have a real good try to break them by bending. Sometimes they go real brittle also. In fact probably better not to use them. Best wishes on the comeback trail.

>Just a thought. Well, two actually. If you'r thinking of
>using your 30 year old balsa just check that it's not gone
>too brittle for practical use. You just might build a model
>that turns into the proverbial bag of balsa bits without
>even crashing.
>And if tempted to use 30 year old yellow nylon props, have a
>real good try to break them by bending. Sometimes they go
>real brittle also. In fact probably better not to use them.
>Best wishes on the comeback trail.

Ian, What makes balsa brittle is the loss of moisture in the wood. I also have a pile of 20 year old wood and restored it by using a humidifier in a closed room. No it didn't warp the wood.
As you know too dry a wood and you can't use CA without a kicker. It needs the moisture to flash off.
Old nylon props also benefit from being put in hot water for about 20 minutes. Yes I know that some say boiling but it really only has to be brought to a boil and then simmered.
Come to think of it thats why coligen is so popular in cosmetic surgery. Fills in the crevises and makes you look 'fresh and dewey' Dennis

Does your engine have a round venturi or a square one?
Bigiron

This is the one I'm referring to. Same as shown in the box picture above.

Chuck,

You certainly used the wrong backdrop for your photo. You'll probably get a lot of questions about that DRA back there. Quite a few musicians read and post here.

Then before it starts, IT'S NOT FOR SALE!

That is a sport 36. Plain bushing main bearing. mildly timed, it is easily started andd easy to adjust. It 4-2-4 runs fairly well but in my opinion likes a rich 2 better. A good 10 X 5 or 10X 6 prop with 5% to 155 nitro fuel with 25% CASTOR oil or more. Some had a reputation for vibrating quite badly, but I found that when they did, more breakin solved the problem.
Bigiron

> That is a sport 36. Plain bushing main bearing. mildly
>timed, it is easily started andd easy to adjust. It 4-2-4
>runs fairly well but in my opinion likes a rich 2 better.
>A good 10 X 5 or 10X 6 prop with 5% to 155 nitro fuel with
>25% CASTOR oil or more. Some had a reputation for vibrating
>quite badly, but I found that when they did, more breakin
>solved the problem.
> Bigiron

Marvin, I have one that has had so much run-in in 20 years that it's about wore out and it still vibrates. Thr other side of the coin is that I have 2 others that don't Dennis

Thanks a bunch guys, all of you. I now know a lot about this engine. All the pics posted are the same as my engine. They sure do have a nice pop when lubed and flipped over. I too am a recent - 6 years ago, re-tread from '60s flying. Got plenty of engines and projects and don't mind lower performance retro engines at all. I've got a nice Fargo-Moorehead Skylarks club profile kit that the 36 would be great on. Going to run a K&B GH 35 on a Nobler, the exhaust is on the outside when inverted and this just somehow makes good centrifugal sense. I'm not sure these engines were know as true 4-2-4 stunt engines, but I've always thought they were a ##### good engine.

Again thanks all.