With a 25 year old Tecumseh, my guess is valve clearance.
Me, I like Castrol 5W30. Castrol cause my last truck had a rod knock, and Castrol was the only brand that quieted the rod knock for more than two days.
that old,,i bet it has ignition points and condenser and may need them changed. i would take carb bowl off and be sure its clean insidetoo,tighten head bolts.. lucas
tecumseh rep said is ok to use 0w30,5w30,10w30 synthetic in tecumseh snow blower engines. i use it in my tecumseh 7 hp tiller engine and it got more power .. lucas
that idea about the valve clearance is a good possability too.
Starts up runs but a few minutes it stalls out. Let it set and starts up again and stalls. Just put a new carburetor on it does the same think.
Check for the spark as soon as it stalls out. It may be the coil heating up or some other part that generates the spark.
I doubt that it could be the hole in the gas cap is stopped up,but have seen engines run for a short period of time and quit and then start back up after a period of time.
It sure sounds like the coil is causing the problem. Loosen the gas cap as soon as it stalls then try to start it.
In line with that, I would verify there is good fuel flow to the carb.
Try blowing through the hole in the gas cap. If you're still not sure that the hole goes all the way through (zigzagging), put it on loose, so air can get in, and see how long it runs then.
Ignitor/coil failing hot
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.