Brodak 40

There has been a lot of discussion about the B-.40's since they came out. I am going to interject a thought It seems to me that a lot of folks have taken the time to disect/examine/study this engine and then have posted what all is wrong with it.

Well, let's go the other way! Are there some issues with the engine? Yes! But they are minor (my opinion). The NVA is a problem with some of them because you can't shut the fuel off. Very simple solution is to install a ST NVA and that problem goes away. You can also file some threads off of the needle that comes with it but I don't recommend that becuase you can also mess up the needle itself.

Prop nut! On some of these the crank shaft is not EXACTLY 1/4 -28 and so there have been problems with using spinner adapters and nuts. Some of them won't even allow you to run the nut that comes with it down to the shoulder or the crank. Chase the shaft with a 1/4 - 28 die and this problem goes away. You don't remove much metal at all and should have no "security" problems with spinner adaptors or prop nuts.

Break in! 9-6 prop, 8 ounces of fuel, 11500 RPM, on bench. Four times the money! Put it in a plane!

It takes about two gallons of fuel before it will "one flip" start everytime but this is just due to time on the engine. After 1/2 gallon it will one flip about 70% of the time.

Performance! I have seen four of these engines on four different planes. They run consistently and are very easy to needle. Very good power. J.D. Falcon on 65' lines. (Plane weighs 41 ozs.) Great tension overhead and breaks 4-2-4 at exactly the right place.

In conclusion! Are there some issues with this engine? Yes! Is it the best stunt engine ever built? No! BUT, (my opinion) is it a great engine for the money? Bet your sweet bippy! Additionally, John B. is aware of the aforementioned problems and is in process of trying to solve them. It's just going to get better

John

To suppliment what John just said, My B-40 was a snap to break in. It wasn't as tight as some of the others I have seen. About 30 minutes on the breakin bench, short (2 min runs) and then put it in my NOVI IV. The Novi had a Fox 35 in it so I could get a really good comparison between the two engines. Like John said, my needle would not close down enough to even get a REALLY RICH run so I replaced it with a ST NVA. I then filed away the bottom 3/32nd of an inch of threads on the needle (being VERY careful to not damage the tapered part). It works fine now, but I haven't reinstalled it back in the engine. I first flew the B-40 in the Novi with the "reccommended" 10 X 5 prop, 10% nitro, 24% oil fuel, and the stock venturi. WOW!!!! Sub 4 second lap speed in a four cycle mode!! I have had combat planes slower than that!!! Go to a 11 X 4 prop. Better but still too fast and not enough time on a tank of fuel (3 1/2 oz). (I can install a larger tank). Mess around with some different props. I am NOT into "re-pitching" props. Tried a cooler fuel 7 1/2 % nitro 22% oil, much better. Tried all the props again. Still too fast and too short on fuel. With 4 inch pitch, not enough pull over head. Ordered some 10 1/2 X 4 1/2 APCs. and also got a couple of Taipan 10 X 6 and 11 X 5 props and cut the 11 X 5 down to 10 1/2. The Taipans worked very well, but the engine seemed to labor and not be up to good power.
The APCs were VERY good but fast and somewhat low on fuel mileage. I turned six different venturis ranging from .275 diameter up to .295 dia. and so far have not checked them all. BUT the .288 is working so very good that I am going to use it for a while. Good speed 5.1 to 5.3 sec laps Good pull through all maneuvers and Very good mileage. 7 min 45 secs on 3 1/2 oz. Like John said, Good one and two flip starts even on inverted starts with the plane on the ground on its wheels. No tendency to flood or bite. My opinion is that it is a better than average engine for most of our applications and for those who do not wish to put up with the hassle of fiddling with pipes, this is a good choice and reasonable price.

How does it compare with my Fox 35?? As many of you know, my Foxs are QUITE strong. The NOVI IV is 630 or so square inch wing and the plane weighs 44 oz with the Fox and 45 oz with the B-40.
The performance is very close with the Fox being a mite slower in lap speed, which in my opinion is better. But I haven't fooled with the B-40 as long as I have with Foxes. I would highly recommend the Brodak 40 if you do not wish to mess around with engines to get the power. Just bolt it on and go fly.

My personal thoughts are that the venturi could be a slight bit smaller in the stock condition. It would be much easier to ream the ID out slightly than build or buy a new venturi. NO, I haven't suggested this to John B!!

This is great information.

I'm just curious if it is a Product Review or a Main Forum item.

The distinction seems awfully blurry these days.

Great post, regardless.

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>This is great information.
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>I'm just curious if it is a Product Review or a Main Forum
>item.
>
>The distinction seems awfully blurry these days.
>
>Great post, regardless.
>
>Cy.

Right now it is an item of interest. People are sharing what they are doing with it and how they are making it work. I think it is fine right where it is at.

I haven't read any of the Brodak articles because I've seen several of these motors in competition and every one of them have appeared to run great. I have talked to the pilots and they have all been happy with the motor. I also know that if your not happy with it, John will take care of you.
Bottom line is I feel it's a win, win motor; it targets the sport flyer as well as the competition flyer.
John Brodak has done so much for control line. This does not surprise me at all that John has put together a quality motor like this.

Like I've said so many times before it's important that we support all the people that manufacture for us. They are the single biggest reason that control line has grown so much over the last several years. Most all of us rely on one or all of these people for every plane we build and fly.

After working with two B 40's, I basically agree with everything said except the fuel mileage. On the second engine, now pretty close to broken in, 3 patterns were flown last week, mostly 4 stroking, lap speeds seemed about right, smallish profile at 48 span, 480 squares and 3.25 oz was a gracious plenty of 7.5%/22 fuel with a 10-15 lap reserve.

The first engine would occasionally make the pattern mostly 4 stroking, same fuel, on an Oriental on 3 oz, 3.25 would have been perfect.

Bigirons Fox 35's are very, very stout. There is no comparison in power between the garden variety Fox 35 that you are likely to get off the shelf and the B 40. My estimate is that it "feels" 20% stronger on the same airplanes. A little stronger than various OS35S' and easier to get good runs out of.

I continue to assert that both B 40 engines flood very, very easily and when minimally flooded feel like they may be dry. No choke and clamp fuel line when filling when hot gets you a likely one flipper. Cold starts require minimal choking. Inverted starts are as easy as profile starts assuming you get the right choking for the engines temp figured out.

The APC 10-5 is the only prop I have ever used on the B 40 on any airplane. Saw no reason to change.

As to venturi sizes, I think a gripe on the first bunch of 6 B 40's first tested by some East coast guys, was that the venturi was too small and was costing power.

No airplane I have experimented on comes close to being too much for the B 40 but I suspect the previously mentioned 44 oz/550 squares is pretty close.

Note that the Brodak site suggests the B 40 on a 670 Sq. inch Legacy with a 10/6 prop. This is not a knock on Brodak and he/they deserve our support for working through the teething problems to bring out a very nice, reasonably priced, out of the box stunt engine. I expect it to continue to improve as minor quality control issues are worked out.

I agree! Brodak 40 is an awesome motor! The first couple of starts are tough but after that, it gets easier and easier! In addition, it gets more and more powerfull with each run!

As an example, I have 2 B40s in two different ships. One has got 1 gallon of fuel through it already, while the other is about 1/4 of a gallon. Both engines are being broken in on the planes! The first one easily spins 11x4 APC(cut down from 12x4) without any wind up. The other winds like crazy with a Rev-Up 10x6. Others fly on 10x5 APC in order to avoid the speedup in the maneuvers.

More and more, I realize how good that motor is! I had it run away after it broke a prop only to come back with more 'gusto' the next time.

There is only one other motor that works like a charm right out of the box for under $100: OS 46LA-S. If anyone knows of a motor that will run as good as B40 for under $100, please let me know as I would love to check it out.

Although I haven't flown mine yet, but the break-in is going nicely. I don't think I've had to flip it more than three times to start it. Starts right up and keeps chugging away. I am slowly having to lean it out on each run and haven't seen anything negative about it.
All of the problems that have been reported on previous B40's don't exist on mine. Maybe I got one of the Mid-week engines that they were really paying attention to. Never buy an engine made on Monday or Friday. Nice thread and bolt action on the prop nut, all engine bolts nice and snug, venturi pointed the right direction, and the funny little lock nut on the muffler actually works well (specially since I replaced it with a tounge muffler). No muffler for the break in though, that goes on when it gets mounted in it's new engine compartment.
So far my B40 seems to be really well built and a solid runner. I can't wait to get it in the air.

LOVE MY B40,
Dave Fincher

I finally got my B.40 on the test stand and as of 6pm today I have 6 two minute runs on it. The first three times I flooded it and it does bite. I had the test stand tank too high and the fuel was flowing into the engine. My fault, not the engines. The last three starts were three or four flips and boy does it have power. My OS .40 FP never tried to pull the test stand up the driveway, but this engine does. Sounds nice and the neighbors yapping little terrier runs into the house instead of barking at me all day. No muffler for break in and like I care about a loud dog. Ha.
I'm using 10% nitro, 22 oil (50/50) and a 9/5 prop to keep the rpms up in the fast four cycle mode. I have not experienced any of the problems others have reported. I will mount this in the ARF Nobler when I have 20 minutes bench run on it. More later,

Went out this afternoon in light winds to put a couple or three more break in flights on the latest B 40 before installing it in the airplane it is going in as I think the break in is pretty much done.
Was adjusting tank and needle at the same time and got a really screaming lean final run. I was impressed that the engine never lost power through any maneuver, never sagged in any way and delivered a fast but solid feeling run upright and inverted and through all loops and some hard corners-no hint of power loss.
Flight time was 8 to 10 minutes on 3.5 oz or so. Piston had browned slightly on inspection. Presumably no damage to AAC construction but I would have preferred that this not have happened.
Again, I think the point is that there was no sag or loss of power anywhere despite an overly lean setting and that a guy could have flown a decent but fast pattern if this were to occur in comptetion.

Has anyone had the sleeve installed incorrectly? Slightly turned .

Scott

>Has anyone had the sleeve installed incorrectly? Slightly
>turned .
>
>Scott
I have 2 B40: both had the sleeve installed correctly.

I have two also, the sleeves in both are correct but the one I picked up while at the Brodak Fly-In does have the needle assy installed wrong. Minor inconvenience considering how great these things run.

Bought two, had to align the sleeves on both.

>Has anyone had the sleeve installed incorrectly? Slightly
>turned .
>
>Scott

Scott, out of three batches of engines that I have received, 18 engines in all, I have seen one that was slightly off--maybe one degree, maybe two, but not enough to make any difference if left that way. I pulled the head and corrrected it.

Ideally you want the sleeve centered in the exhaust, and this is done by "eyeball" and "guess". Nobody puts a micrometer in to measure if the exhaust cut in the sleeve is absolutely centered in the exhaust. And it can be a fooler. If you don't look in exactly with direct light, you can think it is off when it isn't. (I know, it even fooled me. I thought one was off, but when I looked straight in with the light focused properly it was fine.) some engines like the FP series or the Thunder Tigers have a pin that makes sure the sleeve is properly aligned. Ironically, on the FP engines it would be better if it could be turned slightly. The wrist pin would then be centered better, not the exhaust. Does it make any difference in the run? No. Same with the Brodak. If it were slightly off, it wuldn't make any difference. Now, if it were major off...!!

John assembled 50 of the first batch himself from parts. Maybe somebody at the factory "goofed" and got the sleeve on an engine or two slightly off. It is easy to do. It is also easy to correct. Just lower the piston, remove the head, and turn the sleeve. This is something anyone can check before they even run it. Something you should check with any engine. But, certainly, not a problem.

Some of the alignment problems may have been from the batch of motors that were shipped in pieces to dealers to fill orders (these were originally intended to be parts stock). I would imagine that the Russians pay fairly close attention?

See Ya

As of Thursday I have 22 minutes on my B.40. With my finger over the venturi I pull the prop through until fuel gets to the inlet, then three blades, release my finger and flip the prop three times, hook up the glow driver and one flip and it's off and running at a nice 4.Next stop, ARF Nobler. For a fuel tank I have installed a Brodak's "BH-489 A.T.F. 4 oz. Medium Wedge Uniflow Tank". This infor from the label. More later.