My Craftsman 26hp tractor is running extremely ruff, I have replaced the plugs Confirmed that the plugs are working. It runs ruff at all speeds. The tractor was runing just fine a few weeks ago

Stating the obvious there is something wrong with the throttle plate or cable adjustment, this unfortunately is something for somebody qualified as adjusting the throttle plate needs knowledge and a rev counter to make sure the engine does not over speed.

get a spark tester and plug it into one of the plugs after it gets up to operating temperature. test the other one if you have good spark plugs and no spark going through the tester the coil may be breaking down. and needs to be replaced.

theres a filler plug on the back of transmission and chang filter to

If you are talking about the spark plug, I would need the model number of the engine.

If it does start ? But wont stay running , replace old gas with new, cleanout the carb. bowell , and maybe a new spark plug !

Hi, first check the oil. If it smells like fuel, change the oil. Secondly if oil smells ok, check the valve clearances and adjust if incorrect. Let me know if the oil smells like fuel and I will help with a fix to stop it happening again. Regards Phil.

Have you checked for a good spark from plug, if in doubt replace spark plug.

Check the oil and let it run to see if it clears up. Sometimes the oil will run into the cylinder when it is jacked up.

If you changed the belt make sure it did not interfere with the wire that runs from the pto clutch, sometimes that belt can rub on the wire and wear through it,also if you had the clutch off make sure you aligned the steel retainer bolt that sets in the alignment hole on the pto clutch,this keeps the clutch from spring when disengaged if you don't get that pin through the hole in clutch it can push on the clutch and bind it.Also it may be possible to plug that pto switch in backwards.Also if you jumped the fuse out it may now have burnt the switch or wiring somewhere.

go to any auto parts store with your model info as they have a book which will tell them which spark plug is best for u.