Stumped, slow start, jumps to full throttle

Auto Doc's said:
Hi Slomo,

What you are referring to is an air vane governor which controls the throttle when the engine is under load.
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This engine doesn't have what you are talking about. It's not an air vane governor. Just air vane.

Flywheel air pushes on the air vane opening the choke plate. Then the thermostat gets heat from the exhaust port. There is a heat sensitive spring that moves the thermostat arm to push the air vane which holds open the choke plate.

Autochoke has nothing to do with the throttle. They said the engine was not a primer engine. Leaves the other autochoke model possibility. Reason I asked for pictures to confirm this. His engine can have either a primer or autochoke per the parts list.
 
Sorry that it took so long. Busy Day
 

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have you checked the coil to flywheel clearance? Cleaned it to get rid of rust and particles? I doubt if it matters but the flywheel looks like it has been rubbing on the coil.
 
sgkent said:
have you checked the coil to flywheel clearance? Cleaned it to get rid of rust and particles? I doubt if it matters but the flywheel looks like it has been rubbing on the coil.
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Check out the brake pad. That is causing the scratches.
 
This is a single speed or should be set to be a single speed engine as in 3600rpm. If yours has a manual choke/throttle cable, set for 3600rpm and leave it alone. Use the dead man lever to kill the engine as normal.

I didn't see any new fuel lines from tank to carb. Yours looks original to the engine. I would replace it adding a good shut off valve inline. Make sure you have a solid fat flow of gas AT the carb inlet. If you have a slow trickle or nothing, red flag.
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Swapped the carb for one from a good running mower. Mowed the yard fine. But when shut off it would not restart. After sitting for about 10 minutes it would start but would only run slow, never went to full speed. I have a video of it running slow, will try to post it.
 
Sorry, haven't been able to get a video loaded. It started up fine and mowed today, about half way through the yard it popped a couple times and died. When restarted it just ran slow.
 
DId you check fuel lines? Someone said they looked original.

Did you check fuel flow at carb? Remove fuel line at carb and see if it is free flowing. An inline filter could be clogged, or crud in tank clogging the output. It kind of sounds like dirty tank to me. While mowing, the crud in the tank is in motion, settling down around the pickup/drain when sitting.
 
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