5.7/350 Merc gauges dead won't start

[cruzin1a]

Hi all, this is my first post to the forums. I did some reading and got some good ideas to check when I get back down to the boat. I just thought I would float my situation out there for some thoughts and ideas. The boat is a 1988 Cruisers Inc Rogue 2120.

Right now the situation is as follows, All of the gauges on the dash are dead. The motor will crank but it will not turn over and run. Curiously enough every now and again when I turn the key to the ON position the gauges come to life and the boat turns right over and runs. Within a few seconds the gauges go dead and so does the motor. There is no defined pattern to this. It happens randomnly.

I am planning on bypassing the dead man switch from what I have read here. I think I need to check the ignition by pass in the shifter. Not sure how though. I've also readt that the oil pressure sensor can be an issue and I think I read that I should disconect the grey wire from that gauge behind the dash. My thought is a bad ignition at the dash and I thought I would go ahead and repalce it because it llooks like the original.

Any other thoughts would be greatly appreciated.

 

[Don S]

Re: 5.7/350 Merc gauges dead won't start

I am planning on bypassing the dead man switch from what I have read here. I think I need to check the ignition by pass in the shifter.

Don't just start changing parts, check them.
When you turn the ignition switch to the run position, do you have power to the purple wire on the ignition switch? If not, then you need a new ignition switch, if not, you move to the next place in the circuit. It could be the kill switch. Do you have power to it and coming out of it? If you do, move on till you find where the power stops.
The switch in the control is for a neutral safety switch, has nothing to do with the ignition. If it was bad, the starter wouldn't engage.

 

[cruzin1a]

Re: 5.7/350 Merc gauges dead won't start

Thank you very much for the advice. I will check those two things you mentioned and post the results.

 

[cruzin1a]

Re: 5.7/350 Merc gauges dead won't start

I went to the boat this evening. I tested the ignition switch as you said I should. I found that when it was in the on position it was passing 13volts as it should when functioning correctly so I moved on to the kill switch. While getting ready to test the kill switch I moved the wire that runs between it and the ignition and the gauges lit up. I moved it again and the gauges went off and on. There is a crimp on that wire between the ignition and the kill switch. I installed a new crimp and the issue is resolved.

I sincerly appreciate the assistance.

Now on to the Isolator and Alternator...