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Engine basics => Engine set up tips => Topic started by: Richard Koehler on December 27, 2012, 10:01:26 PM
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What brand glowplug are people using in their Brodak 40's. My B-40 has so far destroyed two Fireball R/C longs and a gold Fox.
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Hello Richard, I went with Tom Dixon's choice on the Double Star .40 in which he suggests the Sig R/C long. That plug has worked quite well for my son Shawn for several years now. On contest day of course recently, the plug was not doing so well and was replaced with a Thunderbolt R/C long. I would also think a Enya #3 would also be a good choice. The fuel of choice were using is Powermaster 5-22 GMA blend. I'm curious as to why your taking out plugs. I can see this happening if the engine is quite new. Is the engine mounted in the inverted position? It doesn't take much to choke these engines usually requiring one rotation of the prop. I start my inverted engines upside down and this enables me to see that the venturi is wet inside when the engine is choked. That could be quite damaging to plugs. By far, my B-40 is the most reliable one flip starter I've ever owned. Ken
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What brand glowplug are people using in their Brodak 40's. My B-40 has so far destroyed two Fireball R/C longs and a gold Fox.
What happened to the Brodak plug that came with it?
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Thunderbolt RC Long (x2)
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Stunt folks generally have good success with "go-to plugs" such as the Thunderbolt and the Glo Devil #300, along with the Sig r/c. Others may vary. If you continue to blow plugs, I'd look at too much compression in your Brodak, possibly a manufacturing variation. I might try adding one head shim to slightly
lower the compression, and see if the plug destruction is resolved.
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Richard: the Brodak 40 is, in general, not tough on plugs.
I have John Brodak's very first engine, his personal 40, engine number 1. It has been run in quite a frew different aircraft as well as a variety of props, from 10-6 up to 11-4.
I have run a bit of Powermaster 10-22 (50/50) but mostly Brodak 10-23 (50/50).
The engine has been mounted both upright and profile.
I do not know what plug is installed but, whatever it is, it has NEVER been changed.
This engine, by the way, flew the very first Brodak ARF, the profile Cardinal and now resides in the original prototype ARC Smoothie. It's still one of the easiest starting and best running engines I've ever used.
What Bill Hummel said may indeed be the solution to the problem. If the tolerances are off enough to raise the compression substantially, that could quite well shorten the plug life. Try a few extra head shims and see what happens.
Bob Z.
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TRY... only 1 .. extra head shim first, The HOT RC long plugs work well in the Brodak 40, Plugs such as mentioned, Glo Devil #300 , T Bolt RC Long, SIG RC Long, The Big Bore t Bolt also works well
Randy
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Thanks for the help guys.This is a basically new motor and now I at least know where to start to sort the problem out.
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You might pull the backplate and check for wear marks on it. Aluminum shavings/powder sent through the engine are very hard on glowplugs. There should be a steel wear washer behind the prop driver (from memory). Using an "electric finger" excessively can cause the backplate to get buggered up by the crankpin. y1 Steve
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Another item to ck is the head and backplate bolts. somehow I have accumulated quite a few B40 and all but three are still NIB. I decided to ck the bolts and found most needed to be snugged down between 1/2- 1 full turn. I was quite surprised. In.each engine I was careful not to over tighten. I plan to install one extra head gasket before flying any of these engines.