Glow Plug Burnout

[IBinSaneDiego]

I just broke in a new motor, I have it tuned and running aprox 240 degrees, and running great. I have clean air filters, but now the glow plug is failing rather quickly. The last two appears that the coil was forced up into the plug? Too much compression? Too rich/lean?

 

[Monkey Wrench]

Hard to say without knowing what kind of mill it is, but if you have a head shim for it, may want to try putting that in.

 

[IBinSaneDiego]

Dynamite Mach 427. It has the standard shim... I do after an extra .01 and .02 shims.

 

[olds97_lss]

What percent of nitro? Most "normal" engines are setup to run 15-25%. Running to high of nitro can cause that as well.

 

[robriguez]

if your running 30% you should add a shim. Otherside I can't think why a coil could possibly be pushed up inside the housing....

 

[IBinSaneDiego]

Well yesterday I threw away a bunch of money. I was using O'Donnell 20%., And I added an additional shim. So I bought a couple of high end glow plugs. Each plug died a similar death after about 1 tank each... and ran excellent up until they died. Good temps no higher than 240. Went back and bught some Blue Thunder 20% and some cheap A3 plugs. They lasted alittle longer, but still died the same way. Then some other RC'r dropped by to see what was up... said he never seen anything like it. Made a couple of suggestions which I will try. One about the placement of the fuel line... away from the motor. Maybe the air in the line contributed?? Anybody want to buy a used LST2 with tons of extra parts? Just kidding... atleast not yet. onder2:

 

[olds97_lss]

You ever try running an OS #8? The A3 is to hot for BB use. I always got pre-detonation when I ran those in a pinch. The #8's are more expensive, but I get better power and easier tuning with those in my OS 21 RG.