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Dominick, Marine Mechanic
Category: Boat
Satisfied Customers: 1009
Experience:  25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified
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I have a 1993 v4 140. the idle was gh, 2000rpm.I ran a

Customer Question

I have a 1993 Johnson v4 140. the idle was high, 2000rpm.I ran a decarb solution through. After that it ran fine, but still high. I then rebuilt the carbs. Now the engine misses and sounds out of time.
Submitted: 1 year ago.
Category: Boat
Expert:  Tan replied 1 year ago.

Hello. My name is Tan.

We need to do a spark test and a compression test. Spark must jump a 7/16" gap on a spark gap tester. The compression must be 90+ psi with no more than 15% difference.

Did you mess with any of the linkage adjustments?

Can you do these tests?