M running issues

WidefrontDan · Jul 24, 2016

I have a 41 M and when start up cold it will start up and die at low idle, then when you give it,gas or its under load it will start to run fine but with a slight miss every now,and then. Would that be carb or a timing?

Also when I go to turn it off after Bush hogging or using it for a little while it won't shut off it'll keep clunking for a few times then when it shuts off it'll blow a big puff of white smoke out the breather and blow the oil in the filter out

Janicholson · Jul 24, 2016

Use the choke a little more for cold starts for 3 or 4 minutes (less than 1/2 choke)
The fuel mix can cause a intermittant misfire, as can worn plugs. To get it to stop, make sure the low idle speed is near 500 rpm, and just in the middle of running well on idle mixture. If it still runs on (what it is called) put it in 5th, hold the brakes and let the clutch out as you shut off the ignition. Jim

David G · Jul 24, 2016

I agree with Jim, you have two separate issues going on.

The engine just takes a little while to warm up, might need a little choke until then.

Letting an engine run on is REAL bad for them, it can break rings and pistons. It is usually due to the throttle plate being to far open at idle, which lets in enough fuel and air to keep combusting like a Diesel. Make sure and let it cool for a few minutes then idle it down REAL LOW before shutting it off. I would assume the idle should be down around 500 or less when you close it down completely.

Brownie450 · Jul 25, 2016

Might try opening the idle screw a bit.
Should be set when engine is at operating
temperature, however.
Jim

David G · Jul 25, 2016

The idle mixture screw might be an air bleed on that, so screw it in, others can confirm.

John M · Jul 25, 2016

Problem 1 - As suggested use the chike a little bit.

Problem 2 - Several problems possibly - carbon build up in the combustion chamber, timing off, too hot of a plug, just to name a few. For now, just turn the gas off and let it run out then turn the switch off. Ive never like using the clutch to kill it.

Bob Kerr · Jul 25, 2016

Check your manifold bolts and nuts. It might be a bit loose. Seen that a lot. Also check intake manifold and carb gasket
with carb cleaner and see if speed changes at idle.

M running issues

WidefrontDan

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Janicholson

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David G

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Brownie450

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David G

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John M

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Bob Kerr

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