slight misfire on #1 cyl mariner 40hp 2stroke

j5ffx

Cadet
Joined
Dec 9, 2006
Messages
19
Hi to everyone, how do i trace this fault?
This motor (97 mariner 40hp 2stroke 2cyl 7041203FD) has a slight misfire on number 1 cylinder. it ticks over with a noticable misfire, if i pull the plug off #1 cyl it ticks over very well (sweet). if i pull #2 plug it continues to run but with a eratic misfire! it dosnt change when i rev it up a bit. it has got 2 brand new CDMs fitted, new trigger, new plugs, ht leads, carb kit and clean, compression test was all good =.

i have visually inspected the red stator, it looks good with no sign of a leak/melting, the reed valves are fine, the flywheel magnets look ok and the timing is good with the link and sync set up ok.
.
i have swopped the CDMs, plugs and i read somewhere to swop some green and white wires from the stator or was it the trigger? to try and move the fault to #2 cyl but it dosnt move. the fault is always on #1 cyl.

So can someone tell me the best way to trace the fault? im going to buy a DVA meter and then learn how to use it as i suspect it might come in handy either now or later on.
cheers jeff
 

j5ffx

Cadet
Joined
Dec 9, 2006
Messages
19
Re: slight misfire on #1 cyl mariner 40hp 2stroke

i found the fault, it was the rev limiter. i disconnected the BLK/YELL and BROWN wires from the rev limiter to cut it out of the equation and it then ran fine.
hope this helps others
regards jeff
 
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