My 1993 Johnson 25hp starts up, runs for a few seconds then turns off, then it's hard to start without using the key switch electrical primer. Before it turns off, if I push the key switch primer in, it keeps running, as long as I keep doing it. After it turns off, I let it sit for 10 minutes, and she starts right up without priming and runs fine till she dies again. Repeat same as above.
It ran fine 10 days ago, but was running hot, so I took the heads off and cleaned the water passages (passages and thermostat were totally clogged) and replaced the thermostat with a thermostat that is always open because I cut out the hat. Put in new headgasket, and head cover gasket, and torqued to spec and now re-torqued to spec. I finished the job and ran the motor to test it, and I get the result above. I don't see any relation between my work and the engine shutting off do any of you?
It seems like a carb problem but why would it happen now? I'm stumped.
It ran fine 10 days ago, but was running hot, so I took the heads off and cleaned the water passages (passages and thermostat were totally clogged) and replaced the thermostat with a thermostat that is always open because I cut out the hat. Put in new headgasket, and head cover gasket, and torqued to spec and now re-torqued to spec. I finished the job and ran the motor to test it, and I get the result above. I don't see any relation between my work and the engine shutting off do any of you?
It seems like a carb problem but why would it happen now? I'm stumped.
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