glow plugs

Hi,
my tower hobbies .75 is acting strange. With glow plug ignitor (battery)
attached to glow plug engine runs fine, as soon as a i pull the ignitor off
the engine dies. Have tried multiple glow plugs and it is always the same
thing. Anyone know what causes this symptom?
Thanks,
jeff
Reply to
jeffm
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Two things have happened to my Tower 75 like that. One was low compression, replaced piston and liner. The other time this happened was a very rich mixture. First try leaning it out and if it then starts, readjust your mixture to its optimal setting. Howard
Reply to
Howard
If the plugs are new, I'm gonna guess it's too rich. The raw fuel will drown the plug.
Dr.1 Driver "There's a Hun in the sun!"
Reply to
Dr1Driver
Hmm, sounds like it may be a bit on the rich side. Try leaning it out a little. Maybe try a hotter plug? I had exactly the same problem with a different engine and it turned out to be stale fuel.
- Troy
Reply to
Troy
If you use ATF for afterrun oil it is possible the glow plug has been coated with ATF. This will reduce the effectiveness of the nitro and the glow plug element.
Steve
Reply to
Steve
Possibly running far to rich
Reply to
ray fisher
You're probably running a bit rich and drowning the plug. However, your engine "may" like to run a little rich if it's new so do two things: First, install an OS #8 plug in it because that's a little hotter of a plug that will burn better under rich conditions, and, Second, try leaning the low end needle a little because that's the more likely place that a "drowning" rich setting will affect the engine the way you describe it.
MJC
Reply to
MJC
try a new plug. i had that happen many times and it was always remedied simply by changing the plug
Reply to
PaulBK58
Try an ENYA #3 glow plug, they usually clear up this problem.
Reply to
Rumprider
I believe he said "I've tried multiple plugs...". Dr.1 Driver "There's a Hun in the sun!"
Reply to
Dr1Driver
I believe he said "I've tried multiple plugs...". Dr.1 Driver "There's a Hun in the sun!"
------------------------------------------------------------------------------- The multipule plugs might not have been new. I have seen people put another used plug in when they are having problems....................................................
Reply to
Courseyauto
Meh, if you want a hotter plug use an OS# A3
- Troy
Reply to
Troy
Meh, if you want a hotter plug use an OS# A3
- Troy -------------------------------------------------------------The 8 is the hottest OS plug except for the 4 cycle plug.
Reply to
Courseyauto
Jeff This engine has a rich mid range. When you get the low end and the high end adjusted the mid range is a tad on the rich side. I have changed the taper on the low end needle to solve the problem but first Try a new glow plug. You want a HOT plug with an IDLE BAR. I recommend Thunder Bolt RC Long Hobby People have them. You can also try a 4 cycle plug like OS F. The low end needle should be set on the lean side. If this does not solve your problem order a new carb. for a GMS 76 from Tower.
Reply to
O4U2P
Thanks for all your responses. I was running it rich, apparently this engine likes to start rich then once it's running i lean it out then disconnect the ignitor. Once i do that it runs fine. It is a fussy engine, I swap it out with a O.S. .61 which is not near as fussy and starts easy but I have more fun and more power with the TH .75..I'm not too much of an engine person, I just like to start teh engine and fly and i do appreciate all the useful advise you all have....
Jeff Austin, TX
snipped-for-privacy@aol.comnojunk (O4U2P) wrote:
Reply to
jeffm
Sorry you have been misinformed an A3 is hotter.
See:
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- Troy
Reply to
Troy
Sorry you have been misinformed an A3 is hotter.
See:
formatting link
- Troy
-------------------------------------------------------------------------- --------------------------So much for a logical numbering system.............. i use Enya 3 plugs anyways
Reply to
Courseyauto
Replace the carb with one from the GMS and the problems will disappear.
-- Paul McIntosh
Reply to
Paul McIntosh

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