Nf-ID: #R:ida.liu.se:9961:trsvax:1195667303:000:3216
Nf-From: trsvax.tandy.com!earl    Aug 26 08:23:00 1992



/* ---------- "FAQ? (questions about engines)" ---------- */
Is there any FAQ list for this group? I have a minor problem
with a Webra 6.5cc engine. My engine doesen't run properly.
It starts but stop again after a few secconds. I suspect that
the glowing plug is to cold. How does an engine react when I
use wrong glowing plug?
Goran
*****************************************

   It's hard to answer a vague question. But....

   If the engine's running too rich, it'll cause the glow plug to cool off
and quit, unless the glow plug battery clip is left attached.

   If the engine's running too lean, it'll quit, usually, it'll overheat, sag,
maybe surge a little, then die abruptly.

   If the glow plug is damaged, old, et cetera, it'll cause the engine to quit.
Typically, a damaged plug won't keep the engine lit up properly, after you
remove the glow plug clip, it'll slow down and die, or just die abruptly.

   If there is a fuel line problem, pin holes, poor fuel tank location, bad
fuel lines, and so on; it'll cause symptoms like you mentioned.

   If you have a fuel problem, the engine will run off the prime, for a few
seconds, and then die, as it can't draw fuel properly. If the needle valves
aren't set right, it'll run lean, when you open the throttle and then die.

   .... checking for a bad glow plug is easy, just replace it with a new one.
I assume your using a R/C Webra engine, so I would suggest you try a regular
FOX R/C long plug. Unless your into high performance, tuned pipes and such, the
FOX plugs will work good enough. The Control line plugs may or may not work well
depending on your engine uses, etc. Everyone tends to have glow plug preferencesbut the FOX plugs have always worked well for me without problems.

    If you have a new engine, the initial engine runs and break in's tend to be
extra hard on the glow plug. If the engine is running rich or flooded out a
few times, the heavy fuel droplets cause the glow element to get damaged easily.
If the engine runs lean for a few seconds it can cause the element to melt and
open. During break in, minute metal particles will fly around inside the engine
and interact with the glow plug element causing rapid failure too. Some engines
may have left over machine residue (small metal bits and particles) inside and
these bits can destroy a glow plug in short order too. I suggest on a new engine
that hasin't been used yet, to remove the back plate and flush out the engine
with denatured alcohol, and then re-oil with light machine oil and then put in
the glow plug and install the engine, etc. Some engine's, such as FOX, are
test run at the factory, and thus you would not have to do this flush out task.


***********************************************************************


<This information is provided by an individual and is not nor should be
 construed  as  being  provided  by  Radio  Shack or Tandy Corp.  Radio
 Shack/Tandy Corp has no obligation to support the information provided
 in  any way. > 
						
						Earl W. Bollinger
						@ <trsvax!earl>


"You were in the Clone Wars!", said Luke excitedly.
"Yes", replied Obi Wan, "I was a DOS programmer. But that was before the dark
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