E200txecm 1998

[jjhjrcmh]

What can cause a backfire when starting? Boat ran very good on saturday ran at 4500rpms and accelerated very well. Sunday ran good until eveing then noticed a loss of power down to 3800rpms and slow to get on plane. On monday I went down to check it out and when starting it would backfire and looked like fuel coming out of exhaust. I did a sprk test and found one cylinder not firing all the time. Is it the coil? I put a new fuel pump on boat, replaced the power pack as it shorted out but used older coils that tested good.

 

[Joe Reeves]

Re: E200txecm 1998

Spark test should be made with all spark plugs removed and using a spark tester whereas a 7/16" gap can be set for the spark to jump. The spark must jump this gap with a strong blue lightning like flame.... a real SNAP! The 7/16" gap is important.

A coil can be tested easily simply by switching the orange lead (powerpack to coil) from a known good firing coil to the non firing coil. If this now makes the non firing coil fire properly, then obviously the coil is okay.

What are the compression readings of all cylinders?

 

[jjhjrcmh]

Re: E200txecm 1998

compression on all cylinders is 88-90 psi and I found the coil that was bad. Replaced and she runs like a top, thank you for the reply