Brodak 40

[cory colquhoun]

After reading all the engine manual about running in, it says to run in without muffler, would I do any damage if I use a muffler as I don’t want to annoy my neighbours

 Cory

[Dan McEntee]

   The open exhaust lets more gunk, metal and heat out while you are running it. You are only going to be running it for 20, two minute runs to heat cycle it , if I remember the instructions correctly, so that should not be too annoying. This may sound silly, but try to find the biggest plastic tub you can find, and see if it will fit over your whole rig. Once engine is running and needle set, just cover it up. At two minutes, take it off and shut it down to cool. Or take it to your flying field and get your runs in between your flights.
  Type at you later,
   Dan McEntee

[cory colquhoun]

Job done,wasn’t as loud as I thought, big plastic bin worked great to soften the noise, thanks for the tip Dan.

    Cory

[Robert Zambelli]

Cory - I have run in around 25 Brodak 40 engines, with and without mufflers and found them very user friendly - no overheating.
I use ONLY Brodak fuel, 10% nitro and 23% oil (50/50 castor/synthetic) and never had a problem.
I've also talked to people who have used Powermaster 10/11/11 with no bad issues whatsoever.
A word of caution: I have serviced a number of 40s that were run on straight castor with bad results. The last one I did was varnished up so tight that it would barely go over TDC. Fortunately, easy to remedy.
Do not use straight castor and use no more than 23% total oil. 5 or 10% nitro works just fine.
This a really fine engine that will yield years of excellent performance.
I even converted one for scale (throttle) use by installing a carb from an OS FP 40 - worked as well as the OS.
We have sold over 2,000 Brodak 40s and had only around a dozen come back for warranty repairs.

Bob Z.

[cory colquhoun]

Cory - I have run in around 25 Brodak 40 engines, with and without mufflers and found them very user friendly - no overheating.
I use ONLY Brodak fuel, 10% nitro and 23% oil (50/50 castor/synthetic) and never had a problem.
I've also talked to people who have used Powermaster 10/11/11 with no bad issues whatsoever.
A word of caution: I have serviced a number of 40s that were run on straight castor with bad results. The last one I did was varnished up so tight that it would barely go over TDC. Fortunately, easy to remedy.
Do not use straight castor and use no more than 23% total oil. 5 or 10% nitro works just fine.
This a really fine engine that will yield years of excellent performance.
I even converted one for scale (throttle) use by installing a carb from an OS FP 40 - worked as well as the OS.
We have sold over 2,000 Brodak 40s and had only around a dozen come back for warranty repairs.

Bob Z.

Great Bob , I mix my own at 11 /11 , 8 , 70 , looking forward to mounting it on a plane, had no probs starting it , it tried to lean a bit in the fist 10 runs but settled in for the rest and never missed a beat, if it will fit without too many mods it will be going in a Brodak Nobler I have made to fit a TT 40, if not I will built a twister to start as I’m still not that good of flyer

 Cory

[Robert Zambelli]

I think it would be a perfect match for the Brodak Nobler.
Almost as good as a Fox 35!!!!    

Bob Z.

[Jim Hoffman]

Cory/Dan -

I suspect the big tub covering the motor would slowly starve the engine for oxygen.  How long did you run it?

Did you notice any richening of the motor due to reduced O2 as it ran?

[cory colquhoun]

Cory/Dan -

I suspect the big tub covering the motor would slowly starve the engine for oxygen.  How long did you run it?

Did you notice any richening of the motor due to reduced O2 as it ran?

didnt seem to make much difference in the run ,each run was approx 2 mins , the tub I used was an old horse feed tub which had a couple of holes in it, so I think it was getting enough oxygen

[john e. holliday]

I found on mine that the B-40 still needed some more run time.

[Balsa Butcher]

I think Cory was only talking about the initial 2 or three runs which Brodak suggests be done without the muffler. After that, break in may continue using a muffler, stock one is fine. Plan on 20 to 30 minutes of bench time. After that, it (performance and fuel consumption)will continue to improve as it gets more run time in the air. Excellent engine. 

[Steve Helmick]

Years ago, long before plastic tubs and mufflers were invented, I used to put a large cardboard box behind the engine (in slipstream, opening toward engine) to dampen the noise. Yes, it required a brick or something similar to keep the box from blowing away. There was a very noticeable reduction in noise, plus it collected a lot of oily exhaust residue.

When you start flying it, if the B.40 stops on its own pulling out of a wingover, it's seizing up and needs more running time … OR a cylinder head "cozy" to keep the head hot during the dives. If you do the latter, give it another go without the head cozy after 20 more flights and see if it still seizes. Repeat as needed until it no longer does that...  Steve