1981 BlackMAX v225 - No Spark

Hey Guys . . . I'm fairly new to working on outboard engines, so don't make fun of me too badly for asking some dumb questions. <br /><br />Problem: <br /><br />No Spark (any of the plugs.)<br /><br />History:<br /><br />This engine sat for a few years, but compression is 125psi (+/- 2psi) in all 6 cylinders.<br /><br />Bought the service manual and the clymers guide.<br /><br />Trigger, Stator, and rectifier all test within spec (followed the service manual procedures).<br />Coils, Wires, + wires to switch boxes are all new.<br />and hooked up per wiring diagram.<br /><br />The wires at the base of the High Speed Spark advance module are cut and there is no idle stabilizer. <br /><br />Starter engages and spins the flywheel with no problem. <br /><br />-------------------------------------------------<br /><br />Questions: <br /><br />1. Do you need the high speed spark advance mod. or the idle stabilizer for the engine to run?<br /><br />2. If it's not the idle stabilizer or the High speed spark advance . . . then is there an easy way to test the switch boxes? wiring harness? or key switch?

Re: 1981 BlackMAX v225 - No Spark

Check the kill switch it should be the black and yellow. good luck

Re: 1981 BlackMAX v225 - No Spark

It should crank without idle stabilizer or the hi speed spark advance mod. the manual only gives the test for a running engine.

Re: 1981 BlackMAX v225 - No Spark

Does it crank?<br /><br />If so, it's not the kill switch...<br />If it does and no spark at all, and you're sure the stator, trigger is ok... I'd lean toward the switchboxes....<br />Did you Ohm out the stator and trigger leads?<br /><br />Let us know...

Re: 1981 BlackMAX v225 - No Spark

Thanks Guys!! <br /><br />KClost - The trigger and the stator both test out fine (per service manual tests i.e. ohms fall with the specified ranges) and when I turn the ignition key the starter spins the flywheel. <br /><br />Is it worth having the switch boxes tested by a dealer or should I just spend the $$$ on a new pair. <br />--------------------------------------------------

Re: 1981 BlackMAX v225 - No Spark

First ensure that the switchboxes are grounded.... <br /><br />I'm kind of confused why you whould have no spark at all on any of the cylinders... It's kind of rare that both switchboxes would go out at the same time... But since it has sat for a few years I guess its possible.... <br />I'm not comfortable telling you to buy a set at this time.... But "if" you are sure that there is voltage coming from the stator leads and the triggers are signaling properly (You need to use a Peak voltage meter to confirm that.) Then, it is may guess the boxes are the culprit....<br /><br />You've given us good info on all the other electrical components, so that even further stregthens my guess...<br /><br />What method did you use to test for spark?

Re: 1981 BlackMAX v225 - No Spark

hello<br /> dissconnect the black/yellow wires from the switch box's and retest. the kill switch has nothing to do with cranking.<br />I will agree its rather odd to have both switchboxes fail at once.

Re: 1981 BlackMAX v225 - No Spark

I disconnected the black and yellow wires from the switch boxes and made sure that everything was grounded (according to the wiring diagram) => had spark all the way around.<br /><br />Sprayed some fuel in each clyinder. <br />Three cranks and the engine came alive!!!!!! <br /><br />Thanks guys for your help.

Re: 1981 BlackMAX v225 - No Spark

rodbolt, You are correct about the kill switch.. Sorry about that... <br /><br />But the black/yellow wire<br />Please explain what this did...

Re: 1981 BlackMAX v225 - No Spark

i remeber saying something about the kill switch 2 days ago lol

Re: 1981 BlackMAX v225 - No Spark

CHECK THE MERCURY SWITCH.SEE IF LOOSE OR SHORTED OUT. (BAD SWITCHBOXES BIAS CURRENTS)

Re: 1981 BlackMAX v225 - No Spark

Yep, prolinews, you were right on the money....<br /><br />I feel pretty stupid...