Why is it...........?
 

I have an SH .28 and I have just replaced the glow plug, why is it when I take off my glow heater it will die?

Sorry for the dumb and probably repeated question.

RE: Why is it...........?
 

Could be any number of reasons:

1. bad fuel (it may have absorbed some moisture from the air)

2. bad plug (sometimes they're bad out of the bag - but not often).

3. low compression. If your engine is worn then it may not run without external glow heat

4. the wrong plug for the fuel-type (a plug that's too cold can cause this).

5. engine tuned wrong. If the engine is too rich it may stop when the heater is disconnected

(I'd be picking number 1 though - it's surprising how quickly fuel can go "bad" if left in the sun or with the lid off for even a few minutes on a hot, humid day)

RE: Why is it...........?
 

Plug may be too cold for your mixture setting / itro content

RE: Why is it...........?
 

Did you replace the glow plug in an attempt to fix this problem? OR Has this problem just started since you replaced the plug?

Sounds too lean to me. or a tank problem, tune the motor to peak rpm then richen it a couple hundred rpm then recheck holding the plane with the nose up 45 deg then strait up to simulate a take off.

Tank vent plugged? Muffler pressure nipple plugged? Hole in any of the fuel/Pressure lines?

RE: Why is it...........?
 

I replaced the plug hoping to fix the problem, i also replaced all the fuel lines. I have tried 3 different plugs.

RE: Why is it...........?
 

5. engine tuned wrong. If the engine is too rich it may stop when the heater is disconnected


thats usually the main reason for me second would be a bad plug

RE: Why is it...........?
 

Metallica is right. I somehow thought that it was dieing "taking off" from the ground rather than taking off the heater, sorry if I caused confusion

RE: Why is it...........?
 

I have richened it and leaned it out on the high side and nothing seems to work. First of all I must tell you that I am terrible at tuning and I get too frustrated!![>:]

RE: Why is it...........?
 

If its dieing with heater removed at idle, the low needle is too rich not the high needle. They both need to be set correctly, is there anyone at your club that can tune it for you?

RE: Why is it...........?
 

Thats one of the problems here NO CLUB, i cant even find someone to run with[&o] This is on a LST, do you think it could be the primer on the tank leaking?

RE: Why is it...........?
 

Try some new fuel, that gets my vote

RE: Why is it...........?
 

Schlag,



It looks like you are on your own, then.

You will need to learn how to tune your engine properly and searching the RCU car fora would probably be the best place to start.


Tuning car engines is rather strange to most of us air dwellers...
Plane engine techniques don't work the same for them...