Melted Wire EX330

[GoBig]

I noticed this red wire on my buddy's boat is badly melted. I'm not exactly sure what this is for or how it melted. This is the red wire that plugs into the 60AMP circuit breaker on top of the left valve cover (EX330). There is no visible wire, it just appears that the shielding is melted. We were going to get his boat on the lake tomorrow. Not sure if it is safe to use or if we should replace it before we get on the water. It looks like it has been like this for sometime. Any insight here would be appreciated.

Thanks!

[AuMDLST]

RE: Melted Wire EX330

It appears it was resting against something hot - perhaps the exhaust? What was the closest source of heat? If a heat source was the cause you could use some 3M rubber splice tape to wrap the wire (best temporary option) or some 3M Super 33+ electrical tape (second temporary option). Avoid the heat source after taping and replace wire ASAP.

[jaybird]

RE: Melted Wire EX330

That is either the primary power feeding the 60-amp main power breaker or leaving the breaker feeding the main power to the helm.

Strange it’s only burned on the bottom unless at some point it was laying against the bottom of the exhaust manifold. If it were a result on an overload it would normally burn the entire circumference of the wire insulation not just the bottom and only then if the circuit breaker were faulty.

Is it burned the entire lenght of the wire or only maybe just the area that could have lain on the lower exhaust manifold?

[GoBig]

It is melted virtually the entire length of the wire, from what is visible. I didn't go much lower than what I could reach with an arms length from the top. To jaybird's point, that is what is strange about this melt pattern. If it were an electrical overload, I would expect it to be around the entire circumference. Yet, if it were exhaust manifold or engine block related, I wouldn't expect to see it so high up on the wire. It starts about an inch from the circuit breaker and continues down the bottom of the wire as far as I could reach. Thanks for the tip on the 3M tape AuMDLST. This is an odd one. Here are a couple more shots...

[CradGen2]

I would have that looked at

I would have that looked at. Something doesn't seem right there. No real heat source, and melted a long distance. It could be it was resting against another wire with an issue. Do you see RED melted anywhere.

[swooddc]

RE: I would have that looked at

Is that the wire that comes from alternator. I have seen them do that when you get the wires crossed. it wouldn't run if they were still crossed, but it looks like a direct short to ground happened or is happening.

[Andrew]

RE: I would have that looked at

there shouldn't be anything on the engine that gets hot enough to melt that wire that much.....

[GoBig]

RE: I would have that looked at

Boat runs fine with no electrical issues and from what I can tell, there is no red melted anywhere. All other wires in that area are in perfect condition. Bizarre.

[bchesley]

RE: I would have that looked at

Not bizzare for electrical gremlins. Electricity does weird stuff. I would say that you have a directly shorted wire and need to replace that quickly. I would be willing to bet that somewhere down the line there could be a cut in the wire that touched a ground. Time to start tracing wires.

[DavidF]

RE: I would have that looked at

Make sure the connection at either end of that wire is clean and tight. Poor electrical connections cause an increase in amperage that can melt the wire.

[AirTool]

Re: RE: I would have that looked at

Poor electrical connections cause an increase in amperage that can melt the wire.

polite correction: change "...increase in amperage..." to "...increase in resistance..."

Amps would generally be reduced but the amps going through those poor connections will generate heat at Volts squared over resistance or amps squared times resistance.

The volts used would be the measured voltage drop across the "poor" connection. Voltage drop across connectsion "is bad....really bad"

AirTool

[DanielC]

RE: Re: RE: I would have that looked at

There was a recall for a wiring change on the first EX 330 engines. It applied to Excalibur 5.7 engines serial numbers 420733 to 430242.
If your serial number is in this range, there should be a white tie wrap around the wires going to the fuse block, close to the fuse block, by the bracket that holds the 60 amp breaker.

[DavidF]

Re: RE: I would have that looked at

Poor electrical connections cause an increase in amperage that can melt the wire.

polite correction: change "...increase in amperage..." to "...increase in resistance..."

Amps would generally be reduced but the amps going through those poor connections will generate heat at Volts squared over resistance or amps squared times resistance.

The volts used would be the measured voltage drop across the "poor" connection. Voltage drop across connectsion "is bad....really bad"

AirTool

Well OK, Regardless, the result is the same...burned wires. This usually only happens on high amp wires.

[GoBig]

Re: RE: Re: RE: I would have that looked at

There was a recall for a wiring change on the first EX 330 engines. It applied to Excalibur 5.7 engines serial numbers 420733 to 430242.
If your serial number is in this range, there should be a white tie wrap around the wires going to the fuse block, close to the fuse block, by the bracket that holds the 60 amp breaker.

Looks like this is it. Serial number is right in the middle of this range. Thanks! Just another reminder of how awesome this site is. Is there a recall number that I should reference when I call my dealer? I'll go look through the recall notice section on this site. Thanks everyone for the insight...

[DanielC]

PCM service Update #SUP2002-02, Issued in September, 2002.
This was a quite involved change, changing the charging circuit, power supply to the fuel pump relay, and an alternator wiring harness modification.
It was a change fully covered under warranty in 2003, It should still be the same.
Take the boat to your local dealer, or West Coast Correct Craft.
There was also a recall for an ignition coil wire on these motors. Your coil to distributer wire should be red.