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Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 28339
Experience:  have worked on and around most engine models for 35 yrs./Polaris ATV expert
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I have a 18.5 twinII. It will not start when hot and

Customer Question

Hello, I have a 18.5 twinII. It will not start when hot and starting to back fire through intake when under load, getting worse. Help
Submitted: 1 year ago.
Category: Small Engine
Expert:  Curtis B. replied 1 year ago.

This is the older flat head engine. DOes it have lots of hours on it? I had one and it started ok, but lost power as it warmed, and would not start hot. The valves had lost all clearance and required the valves to be opened u to .006 inch. Problem is the valves have to be removed and the tips ground off, to get clearance!

Expert:  Curtis B. replied 1 year ago.

my response shows as customer!