Can't figure out missfire

bertsmobile1

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OK
So you have a flywheel PTO
It is still not the timing key
The timing key is 1/2 in the crank shaft & 1/2 in the flywheel
The flywheel is the big round thing with the magneto magnets on the outside & the alternator magnets on the inside .
 

Hammermechanicman

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It can be the flywheel. Some engines the keyway is milled into the taper of the crank and all you see is the key in the flywheel and none in the crank
 

slomo

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Take some wider pictures of the flywheel.
 

tkos115

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Only difference between these pics and the orginal one is I have the nut and metal spacer in place in these pictures. I know the flywheel isn't under the engine where the belts attach.

I'm probably just gonna send this thing down the road. It was free and I'm pretty much done messing with it. I have set littlerly everything I can to spec, replaced everything, swapped everything, and tested everything and nothing has made a difference. Short of splitting the engine and replacing stuff, it's all in spec and adjusted by the book.
 

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slomo

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So assuming that key is 100% intact, I would say rule out the key and abnormal timing. Again I'm no Tecumseh expert like others on here.

WHICH, after rereading this one, takes me back to the carbs. Running rich and popping, adding choke makes it worse......... I would Bertsmobile1 boil clean those carbs. Use a bread tie (plastic cover removed) and rod out all holes both ways.

As sgkent is preaching on, sync those carbs. (y)
 
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sgkent

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so until the carbs are synced that issue cannot be ruled out. Was the exhaust cleaned out, meaning are there any screens or catalytic converters that can cause excessive back pressure?
 

slomo

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Is there a fuel pump on this? If so do you have good fuel delivery AT the carbs?

Air, fuel, spark and compression.
 

tkos115

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I synchronized the carbs a little while ago today by the book. Made pretty much no difference. I did it 3 times to make sure and it didn't change anything. It does have a fuel pump and it is working correctly. I boiled the carbs a few days ago and no difference. I even put two brand new ones on and it didn't change anything. Compression is good, and so is spark. I put a new muffler on it as well since the old one was rotted out and rattling but other than the noise level the engine runs the same. There are just two exhaust pipes, one from each cylinder that go directly into the muffler. Both of those are clear and open.

I think this engine is just possessed or something.. I've never had an engine be this weird when littlerly everything is within spec that I can check without splitting the block. But the cam lift seems good since all pushrods move up and down the same amount.
 
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VegetiveSteam

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Only difference between these pics and the orginal one is I have the nut and metal spacer in place in these pictures. I know the flywheel isn't under the engine where the belts attach.

I'm probably just gonna send this thing down the road. It was free and I'm pretty much done messing with it. I have set littlerly everything I can to spec, replaced everything, swapped everything, and tested everything and nothing has made a difference. Short of splitting the engine and replacing stuff, it's all in spec and adjusted by the book.
I haven't read every post but have you taken the flywheel off and held the flywheel key in your hand? Bad fuel or trash in the fuel could of course affect both sides but I would doubt both ignition modules went bad at the same time. If you're still working on it check the flywheel key and you have to take the flywheel off to do that. If that is good I would check valve timing next. I won't go into that now since I don't know if you've already junked it but if you're still working on it, checking valve timing is pretty simple to do and only requires removing one valve cover.
 
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