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Old 06-17-2012, 08:14 PM   #1
deason
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Default Dle 20 idle problems

I am having problems with the idle of a dle 20. Past 2400 rpms, she runs like it should-good, clean response. It turns a xoar 17/6 prop at 8400 rpms. But once you go back to idle, it will act like it is loading up and die. After it dies, it is almost impossible to start back unless you let it sit for about 10 min.

I have replaced the spark plug (ngk), replaced carb (new) and replaced tank and lines.
BTW, out of the box this thing ran great. good smooth idle and top in. It has been in 1 crash due to firewall failure on edge 540. Right after the crash, I installed on another plane and it started the problem but not as bad as it is now. Over the past gallon of gas, it is getting worse and worse.

Does this sound like a module going bad?

Thanks....
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Old 06-17-2012, 08:49 PM   #2
Low_Cal
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My guess is its overheating. Check cylinder head temperature if you can.
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Old 06-17-2012, 09:06 PM   #3
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Quote: Originally Posted by Low_Cal
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My guess is its overheating. Check cylinder head temperature if you can.

What should the temp be and what would make it overheat besides running lean?
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Old 06-17-2012, 09:52 PM   #4
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If it loads up and dies at idle, that generally means the low end is too lean. Back it out about 1/4 turn or so, then tune the high end for best RPM, then re-tune the low end until the motor transitions well when you quickly move the stick from idle to fast. When you return it to idle, it should idle stable for as long as you want. If it loads up, the low end is generally too lean. If it has rough transition, then the low could be a little rich.

If this is a new motor, just get it running well, don't worry about getting the absolute maximum RPM out of it until you get 3 or 4 gallons through it.... it needs to break in and get the rings seated well.
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Old 06-17-2012, 10:14 PM   #5
deason
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Quote: Originally Posted by reyn3545
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If it loads up and dies at idle, that generally means the low end is too lean. Back it out about 1/4 turn or so, then tune the high end for best RPM, then re-tune the low end until the motor transitions well when you quickly move the stick from idle to fast. When you return it to idle, it should idle stable for as long as you want. If it loads up, the low end is generally too lean. If it has rough transition, then the low could be a little rich.

If this is a new motor, just get it running well, don't worry about getting the absolute maximum RPM out of it until you get 3 or 4 gallons through it.... it needs to break in and get the rings seated well.
Ive done this earlier before original post, it doesnt seem to help. Also, it is impossible to start afterwards unless you let it sit for 10 min or so. As info, it has about 2 gal of fuel through it since new...and when I take the plug out to inspect, it is black.

Last edited by deason; 06-17-2012 at 10:16 PM. Reason: edit
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Old 06-17-2012, 10:50 PM   #6
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After you run the motor and shut it off (or it dies)... take a look at the fuel lines... is there fuel bubbling back into the gas tank?

If so, it could be a couple of things... either your carb is getting too hot from the exhaust (not likely on a single cylinder motor) or you may have a problem drawing fuel from the tank to the motor. Check and make sure the vent line is clean and can get air into the tank.
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Old 06-17-2012, 10:59 PM   #7
deason
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Quote: Originally Posted by reyn3545
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After you run the motor and shut it off (or it dies)... take a look at the fuel lines... is there fuel bubbling back into the gas tank?

If so, it could be a couple of things... either your carb is getting too hot from the exhaust (not likely on a single cylinder motor) or you may have a problem drawing fuel from the tank to the motor. Check and make sure the vent line is clean and can get air into the tank.
Will do on the next run....
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Old 06-18-2012, 12:49 PM   #8
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Over 400*F is too hot. Sounds like its running hot and lean. The carb may be vapor-locking from the heat.
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Old 06-25-2012, 10:52 PM   #9
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Default **UPDATE**

Tried everything and finally came to the conclusion it was the ignition module. Ordered one and installed and she purrrrrrs like a kitten and runs like a champ.

An old gas guru once told me that "Its either gas or spark..... if its getting gas, its gonna be the spark". By gosh, he was right.
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