Timing Adjustment 1978 140 Hp Evinrude

[danjmartin]

" Hey Joe,

You suggested re

" Hey Joe,

You suggested retarding the timing on my 140Hp Evinrude (high ring pistons) by 4 degress. Two questions, 1) why would that help? 2) how do I do that?

Thanks, Dan

p.s. got the motor to start last night and approx. 120psi in the cylinder (matching the others) "

 

[joereeves]

"Dan... The factory timing was

"Dan... The factory timing was okay when the quality of gasoline was high, but later that quality dropped. The low quality of gasoline coupled with the full spark advance of the engine when it was built resulted in piston damage. No need to go into the technical aspects of it though.

Remove the s/plugs. Rig up a spark tester so that you can connect a timer light to #1 cylinder. Set the throttle to full throttle, full spark advance. Have the timer base pressing on that rubber stop. Spin the prop if need be if the engine is going into forward gear so that the dog and gear lobes mesh properly. Crank the engine, using the timing light aimed at the flywheel and the timing pointer.... set the timing by adjusting the timing advance screw that has the rubber stop. Set it to 4° less than what is called for.

Joe"