no fire on 4.3 chev v6 mercruiser

[hydrick]

Re: no fire on 4.3 chev v6 mercruiser

i was mostly kidding.
usually if the neautral safety is activated the engine won't turn at all.

you start questionong alot of scenarios when you're down to one last thing.....a 380.00 module, lol

 

[dirtyoldman]

Re: no fire on 4.3 chev v6 mercruiser

I wasn't talking about the neutral safety switch.

 

[dirtyoldman]

Re: no fire on 4.3 chev v6 mercruiser

Before the module on the troubleshooting chart they should have you check the rotation of the distributor when cranking, like I mentioned earlier. If you have spark at the coil, but none at the plugs it could be that the distributor isn't turning. A broken timing chain can do this too.

 

[hydrick]

Re: no fire on 4.3 chev v6 mercruiser

yea, i checked that when 1st mentioned.thanks
i'm off to the lake to work on it coil in hand.
i'll update tomorrow.

 

[Reel Poor]

Re: no fire on 4.3 chev v6 mercruiser

Check the shift interrupt switch, it could be stuck. Disconnect grey tach lead (there are two grey leads, one to the control module and one to the tach) from negative side of coil to eliminate/isolate shorted tach.

 

[hydrick]

Re: no fire on 4.3 chev v6 mercruiser

Check the shift interrupt switch, it could be stuck. Disconnect grey tach lead (there are two grey leads, one to the control module and one to the tach) from negative side of coil to eliminate/isolate shorted tach.

you must have mental telepathy,lol
i got home jumped in the boat threw in the coil,nothing.......
i had a dealer loan me a "module just in case" i never even tried it.
i kept going back in my mind to the shifter. only problem is this particular boat is not even supposed to turn over if the neutral switch is activated.
so take a few sips of beer,scratch my head,kick the dog...just kidding about the dog, and asked my wife to move the shifter.
well it's working fine but i notice the switch is barely activating.i look a bit close, in there was a small piece of black plastic about the size of a dogs toe nail with jusssttt a smidget stickin from swith housing.
pulled it out, yold her to hit the switch and
she's running like a champ again.
thanks all for your help.

 

[Don S]

Re: no fire on 4.3 chev v6 mercruiser

There is a big difference between a neutral safety switch (located in the shifter control) that prevents the starter from engaging, and a shift interrupt switch (located on the engine) that kills the igntion for a split second when coming out of gear.
Obviously you are talking about the shift interrup switch but calling it a netrual switch. Correct?????

 

[hydrick]

Re: no fire on 4.3 chev v6 mercruiser

correct.

 

[hydrick]

Re: no fire on 4.3 chev v6 mercruiser

which also would explain why it was turning over eh dons?

though different subject, what should i be looking for regarding a sticking in forward gear periodically?
in other words some days ,though no rhyme or reason, it'll take a notion to stick.

 

[Haut Medoc]

Re: no fire on 4.3 chev v6 mercruiser

The shift interrupter switch is what enables the load to be taken off of the gears & allows them to disengage, by grounding the ignition circuit......
Your "sticks in gear" condition is related to that switch, I'd wager....
You should lube the pivot points on your shift plate....
If that fails to do it, your lower shift cable is on its way out......
​

 

[hydrick]

Re: no fire on 4.3 chev v6 mercruiser

thanks haut medic.