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Old 07-10-2009, 06:13 PM   #1
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Default Engine starts but stalls after throttle increase. Help!

I was driving my car around in circles at a dirt parking lot and it was running fine, but all of a sudden it stalled. I let it sit for awhile, and when I started it back up again it immediately stalled when I increased the throttle. If I increase the throttle very slowly it will run fine at very low speeds, but if I increase any more than about 1/4 throttle the car stalls. Since I lack a starting mechanism at the moment I'm not sure if its out of tune, but it was running extremely well before and I didn't change environments or anything. I also periodically spit a giant wad of spit on the engine head while running it in this parking lot, and every time the spit evaporated in 4+ seconds, so I don't think I overheated the engine. The air filter was a two stage well oiled air filter which stayed on the engine the whole time. What could be causing this? The engine is a Macstar .28.
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Old 07-10-2009, 06:17 PM   #2
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Its obviously way too rich. With all the problems you are having I would try to find someone at the closest track to help you with it, not the lhs.
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Old 07-10-2009, 06:19 PM   #3
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Just sounds like a bad glow plug to me
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Old 07-10-2009, 06:27 PM   #4
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Theres really no telling what it is. Diagnosing a problem on the net is pretty much useless without being able to troubleshoot the actual engine. If I were him I would find someone with some experience to help him out with it.
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Old 07-10-2009, 06:40 PM   #5
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Theres really no telling what it is. Diagnosing a problem on the net is pretty much useless without being able to troubleshoot the actual engine. If I were him I would find someone with some experience to help him out with it.
I agree completely, but changing to a new plug is one thing eliminated..God I could be so rich if I could diagnose and fix problems on-line
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Old 07-10-2009, 07:57 PM   #6
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Could be an air leak or a cracked case also.. hard to diagnose over the interwebs.
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Old 07-10-2009, 08:40 PM   #7
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What does this have to do with the glow plug? I already said it starts fine. Correct me if I'm wrong but doesn't the glow plug become a fancy hunk of metal after the engine is started? I was under the impression it served no purpose after it started.
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Old 07-10-2009, 08:45 PM   #8
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Quote:
Originally Posted by sokar View Post
What does this have to do with the glow plug? I already said it starts fine. Correct me if I'm wrong but doesn't the glow plug become a fancy hunk of metal after the engine is started? I was under the impression it served no purpose after it started.
glow plug stays hot after you take the ignitor off from the cycle of the engine. its just like a diesel
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Old 07-10-2009, 09:42 PM   #9
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glow plug stays hot after you take the ignitor off from the cycle of the engine. its just like a diesel
and if your glow plug is bad guess what happens!? ...your engine stalls..Garfield just try a new plug..If it does the same thing, that's one problem you eliminated

You cant go forever with 1 plug anyway..you did change it after you completed engine break in right?
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Old 07-10-2009, 09:55 PM   #10
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and if your glow plug is bad guess what happens!? ...your engine stalls..Garfield just try a new plug..If it does the same thing, that's one problem you eliminated

You cant go forever with 1 plug anyway..you did change it after you completed engine break in right?
I have not replaced the plug since I bought the car.

But I'm still confused. How does the plug stay hot after the ignitor is disconnected and there is no power to it? And even if it did stay hot, how would that affect the combustion? Isn't the chamber hot enough to sustain the combustion without the heat of the glow plug?
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Old 07-10-2009, 10:07 PM   #11
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LOL, no the plug ignites the fuel! That's how it stays hot and that's how
you get combustion!
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Old 07-10-2009, 10:16 PM   #12
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I have not replaced the plug since I bought the car.

But I'm still confused. How does the plug stay hot after the ignitor is disconnected and there is no power to it? And even if it did stay hot, how would that affect the combustion? Isn't the chamber hot enough to sustain the combustion without the heat of the glow plug?
While the engine is idling screw the glow plug out and see what happens. You have the plug on tight right?
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Old 07-10-2009, 10:21 PM   #13
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A good writeup on how glow plug works and how to select the right one to use.

http://www.bsrcc.com/glowplugs.htm
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Old 07-10-2009, 10:28 PM   #14
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First RC Nitro lesson..Most glow plugs (especially standard type like you have) will be useless after engine break in. Your manual should have told you to change the plug after break in..Its good that your asking questions and leaning..now change the damn plug
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Old 07-11-2009, 03:33 AM   #15
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Quote:
Originally Posted by Jaz240 View Post
First RC Nitro lesson..Most glow plugs (especially standard type like you have) will be useless after engine break in. Your manual should have told you to change the plug after break in..Its good that your asking questions and leaning..now change the damn plug

+1
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