[ccski]

Hey folks. Had the 800 running since spring, rebuilt the clutch and mower deck. Runs strong but has one issue. when travelling a direct bump will cause the wisconsin s7d engine to sputter for a second or two then come back to speed. Thinking something grounding in the primary but have been unable to find anything worn thru. just thought of the keylock perhaps shorting? gonna try that next before venturng under the flywheel. Points and condensor seemed ok after adjusting gap, (was very tight and thought I had it there but still same issue after gapping) to 0.020.

Thanks for any suggestions.

 

[29 Chev]

Check for a loose condenser wire or other loose connections if you think it is electrical in nature - could do the wiggle / jiggle test by moving the wires with a screwdriver as the engine is running. Could also try tapping the component locations with a screwdriver handle or wooden stick to see if it sputters. Just suggestions that you could try.

 

[ccski]

Thanks Dave did all of the above can’t seem to find anything wrong pulled the fly wheel didn’t see anything obvious there. Will keep plugging along all part of the fun right. Can’t think what else would cause it to stall slightly after a sharp bump for maybe two seconds then build
back to regular speed

 

[4getgto]

Do you think you're losing spark or gas ?
My first thought was the maybe the float in the carb bouncing around...just a wild thought.

 

[ccski]

My first thought was spark because it happens within a second of the bounce. Revs drop then recovers. I have done nothing with the carb figuring if it runs good 99.9% of the time why get into looking for parts. One thing I did notice is the bottom of the gas tank height and the in take of the carburetor height are nearly identical very little offset for gravity feed. Do you think a carb could react that quickly?

 

[EricFromPa]

Do you think you're losing spark or gas ?
My first thought was the maybe the float in the carb bouncing around...just a wild thought.

Yep that will do it. If the float is set to shutoff a bit early the fuel will slosh away from the jet when you hit a bump. I've had that problem with alot of carbs that have a side mounted or angled jet that sits up off of the bottom of the bowl a bit. Walbro Kohler carbs do the same thing if you make the float level with the carb body because they have an angled side mounted main jet in them.

 

[ccski]

Thanks 4getgo next step dig into the carb.

 

[4getgto]

Thanks 4getgo next step dig into the carb.

Wouldn't be to hard to take the bowl off and see what the float looks like.
You have a problem that may be tough to replicate.
May sound silly but what are the chances of bouncing the tractor around with it sitting still and have spark tester on one of the plugs and watch the spark ?