Author Topic: 038 diagnosis help. See video  (Read 1828 times)

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Offline Mark71gtx

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Re: 038 diagnosis help. See video
« Reply #10 on: September 29, 2015, 08:24:19 pm »
Well, I put in the new plug and put the settings on the carb at 1 and 1 and it still did the same thing.  I played with the screws and nothing helped.  A guy on another board said the choke flap could be the problem.  I removed the filter and that was the #%$@-&$ problem!  Apparently the aftermarket filter I bought is a pos...

Offline jmester

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Re: 038 diagnosis help. See video
« Reply #11 on: September 29, 2015, 08:48:53 pm »
Glad you got to the bottom of it.
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Offline 3000 FPS

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Re: 038 diagnosis help. See video
« Reply #12 on: September 29, 2015, 10:34:08 pm »
That is right I forgot about that.   The choke is in the air filter and is held opened with a spring inside the filter.  I have seen the spring pop off before and then the choke flap flops around.
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Offline Al Smith

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Re: 038 diagnosis help. See video
« Reply #13 on: September 30, 2015, 04:02:06 am »
Another problem that seems to crop up on the 038 series is the annular buffer shock mount which is on the left hand side aft of the engine .

These can become worn out allowing the intake boot to become stretched which will tear them on the under side .It's nearly impossible to tell if the boot is damaged unless it's removed and inspected .Obviously with a slight tear it won't leak air all the time and will cause a lean out at high speeds .Won't happen all the time though .I've changed around 4 or 5 of these things along with the buffers .

Offline Mark71gtx

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Re: 038 diagnosis help. See video
« Reply #14 on: September 30, 2015, 09:04:20 pm »
New trouble.  It seems this is not my only problem.  I still can't get it to run right.  It runs best with the high side turned all the way in.  It runs Super rich.  Muffler is wet inside from fuel. I pulled the carb apart and everything looks decent.  Carb holds vacuum. What is the problem?

Offline Moparmyway

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Re: 038 diagnosis help. See video
« Reply #15 on: October 01, 2015, 07:44:46 am »
New trouble.  It seems this is not my only problem.  I still can't get it to run right.  It runs best with the high side turned all the way in.  It runs Super rich.  Muffler is wet inside from fuel. I pulled the carb apart and everything looks decent.  Carb holds vacuum. What is the problem?
Is this with the air filter removed ?

Offline Mark71gtx

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Re: 038 diagnosis help. See video
« Reply #16 on: October 01, 2015, 08:11:05 am »
I put the original filter back on with a heavily tensioned spring.  It still doesn't work like it should with it on or off.

Offline Moparmyway

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Re: 038 diagnosis help. See video
« Reply #17 on: October 01, 2015, 08:16:24 am »
Is the saw real rich with the air filter off and the high speed needle seated ?

Offline Mark71gtx

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Re: 038 diagnosis help. See video
« Reply #18 on: October 01, 2015, 08:18:30 am »
Yes.  I pulled the plug and it was wet.

Offline Mark71gtx

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Re: 038 diagnosis help. See video
« Reply #19 on: October 01, 2015, 08:22:19 am »
I pulled the carb and the arm for the needle was slightly up, so I removed it and bent it until it sat flat like it was supposed to.  It is still rich.  I will check again tonight to see if I got the diaphragm and gasket backwards.  That is the only other thing I can think of.  This is the only carb I can remember working on that had a plastic fuel pump center.

 

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