Ok Merc guys,here is a good question

Working on the pontoon from he!!....

1991 75 hp 3 cylinder.
Finally got spark to the ignition after replacing the switchbox and fixing some wiring.
Engine has good compression,good spark and is getting fuel but will not fire one bit.
No spit,sputter,backfire or anything...
My next thought is the flywheel has slipped and its so far out of time it won't run.

Where do i go from here? I am used to working on Evinrudes but this Merc has me puzzled...

Re: Ok Merc guys,here is a good question

Physically put #1 piston at TDC and see where mark on flywheel is.
If magnet relationship is out of sync with TDC the trigger is reading
at the wrong position.
How far of a gap will your spark jump?

Re: Ok Merc guys,here is a good question

How long has it been since the motor was run? Just yesterday I had trouble with my 1971 85hp Merc...hadn't run in awhile, had to rebuild the starter, rewire everything etc. Great spark, but no go. So I took a small spray bottle and put gas from my tank in it and sprayed directly into the cylinders, put the plugs back in and cranked over. Turns out it just needed those couple primings to get the fuel circulating. Motor runs again =). It's somewhere to start. If it doesn't want to go with fuel in the cylinders, then you might be having some timing issues. This method is easier than getting into the timing. Hope this helps.

*edit* it's a 1973, I was thinking of my '71 evinrude 40hp

Re: Ok Merc guys,here is a good question

agree with topol 86 100% if you take the plugs off and spray a lil 50:1 right into the cylinders and you still dont get as much as a sputter, then its definate timing issues, but if it temporarily cranks over for a few seconds then its a gas issue

Re: Ok Merc guys,here is a good question

Did the premix in the carbs and no go.Not even a pop.

Starting to think the flywheel slipped or its a timing issue.
I have also been told a bad regulator can cause it to try and start backwards.
It was getting dark so i didn't think to check that.

I guess its time to pull the flywheel. Got to order the puller being there are no threaded holes in the flywheel for another puller.

Thought i had the job finished when i got good spark jumping the tester.

Thanks for the help guys!