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Craig
07-26-2005, 08:03 AM
OK, maybe someone here has had this issue. The boat runs fine. Then without warning it'll develope a miss of sorts. Everything just dies for a split second, engine, gauges etc. Just like someone cut all power for a split second. As you run it'll get worse. I've checked every wire connection I can see including the grounds on the engine, the wires to the starter and the solenoid. Replaced the relay on the back of the motor, next to the circuit breaker. I have an MSD marine box, but given that the gauges all drop dead also, I don't think I can blame that box. Looked at the Perko batterry selector switch, but the connections were tight on the back. Had the alternator checked today, it's OK. I put a new ignition switch in this weekend, but haven't had a chance to go out again and test. Just looking for suggestions on anything else to check here at the house.
Craig

Sleek-Jet
07-26-2005, 08:07 AM
I had a car that used to do this. Turned out the postive battery cable was just about gone with corrosion. It was corroded down in the cable, not at the ends like you would think.
You might try changing that out if you haven't already.

Desert Rat
07-26-2005, 08:20 AM
Don't know your motor package but alot of engines use the large round connector mounted to one of the exhaust manifolds.. Almost if not all of everything on the engine runs through this connector. Have heard of people having problems with this connector getting loose and making and breaking contact. I have my straped together just so I don't have to worry about it. Give it a shot if it applies to you motor.

Froggystyle
07-26-2005, 08:24 AM
It is almost certainly a bad connection. Probably a butt connector somewhere in the harness that joins your main power line to the rest of the harness. Forget ignition as a problem, if your gauges are dropping you have a source problem.
Grounds are a good source of problems, power are also a good source. This is one of the many reasons I don't put any connectors in line with our power and ignition circuits. All terminal blocks and soldered terminals in accessible places. This allows better testing.
The culprit is likely to be the 10 gauge wire coming off of the starter that goes to your alternator and main ignition harness.

Craig
07-26-2005, 08:27 AM
Yeah, it has the big Merc connnector on the back of the motor, I've looked at that and it seemed OK. What sways me from that connector is that the gremlin also effects the bildge blower which isn't run through that connector. I will take another look at the battery connections as well. I think if I go out next weekend and the ignition switch didn't cure it, I'll experment with the battery switch, put it in the 1 or 2 position and see if it keeps doing it. I was also considering if it acts up, running a hot wire from the battery directly to the IGN terminal on the back of the ignition switch. I'm thinking this would bypass all the connections between the battery and the ignition switch. If it still does it, I need to trace forward of the ignition switch. Think that would work?

Craig
07-26-2005, 08:28 AM
It is almost certainly a bad connection. Probably a butt connector somewhere in the harness that joins your main power line to the rest of the harness. Forget ignition as a problem, if your gauges are dropping you have a source problem.
Grounds are a good source of problems, power are also a good source. This is one of the many reasons I don't put any connectors in line with our power and ignition circuits. All terminal blocks and soldered terminals in accessible places. This allows better testing.
The culprit is likely to be the 10 gauge wire coming off of the starter that goes to your alternator and main ignition harness.
Thanks Wes, I'll look at that, would that be the yellow one with the red stripe?

Dave C
07-26-2005, 08:31 AM
don't forget the grounds too!!!!!.....
also make sure your batterys connections are tight and clean too. They like to loosen up.

SummitKarl
07-26-2005, 08:32 AM
Am going with the Key switch, or the power line to the Key switch.
if ALT is good it don't need to be hooked to the battery to run, this is the best and easy way to check the alt when the motor is running pull the positive cable on the Batt, it should still run
MSD = Might Spark Don't know, make sure it's in a cool place, I strapped a 12vdc PC power supply fan to mine, no problems from there on..

Desert Rat
07-26-2005, 08:36 AM
DO NOT bypass your circuit breaker protection!!! I can't stress this enough!! If you have some type of major short to ground vice an open circuit you will source ALL your battery current throught this baypass wire and that is NOT a good thing! I think Wes has you on the right tract. Find where your blower connects up to power and it should be upstream (towards the battery) from there. It would have to me the master ground to kill everything. look at that too!

Dave C
07-26-2005, 08:38 AM
not unless he fuses the bypass ;)
DO NOT bypass your circuit breaker protection!!! I can't stress this enough!! If you have some type of major short to ground vice an open circuit you will source ALL your battery current throught this baypass wire and that is NOT a good thing! I think Wes has you on the right tract. Find where your blower connects up to power and it should be upstream (towards the battery) from there. It would have to me the master ground to kill everything. look at that too!