undecided need help

[toonin22]

my co worker was working on his 98 200 horse offshore merc because he for a lack of a better words set the engine on fire. the regulator/rectifiers were charred bad. he was installing the new ones and instead of solder or bullet connectors he put butt connectors but before putting the wire in the butt connector he puts silicone in the connector then crimps the wire. Good Idea? I dunno i can see the pros and cons of it. Would it add resistance? or would it make for a good insulator?

 

[Mi duckdown]

Re: undecided need help

First of all why did the engine catch on Fire.?

 

[toonin22]

Re: undecided need help

I was told that the where the wires are located over time from the heat of the block and being tampered with could cause the fire. Do you have any input as to the culprit or how to check and find what could of caused it. The wires and the lower regulator were the only things burnt. I would say about four inches of wire were gone and the insulation was burned up on the upper regulator wires. Also i noticed the trigger wires were extremely soft. I wanted to check the stator but he had silicone in the connectors and i wasn't about to stick my meter leads in that sticky stuff. On another note he was also having problems with his starter at the same time and he said the problem with the starter was ongoing for the week prior to the fire, (going to do a voltage drop test on the starter circuit in the am.) The way he was talking at dinner last weekend was that he laid on the started pretty hard to get it started. He said around twenty min i wasn't there. That would cause an increase in ampreage but I didn't think that the starter would do that. Actually could a faulty diode allow starter solenoid to feed power back into the regulator and that mixed with excessive current flowing on the high amp side of the solenoid maybe melt the wires allowing them to short once the engine was finally started? Any knowledge you could share would be appreciated.

 

[j_martin]

Re: undecided need help

Actually, the design is faulty. The yellow wires and bullet connectors are carrying 20 amps at full load, which is what would happen if the battery were deeply discharged. Those are 10 amp connectors, so they tend to overheat. That causes corrosion, causes more heat, etc. A lot of the heat will go down the wires into the regulator itself, and especially with the old clear potted ones will usually burn them down.

The red wires carry 10 amps apiece. Within spec for the connectors.

I wired up my 40 amp system on the bass boat to recharge all the batteries on board when underway. It took a week or two to take out both clear potted regulators. I replaced them with the black 6 wire ones and it took about a week to take out the bullet connectors. I've since soldered and insulated the yellow wires, and it works like a champ. It pulls enough power off the engine to take a coupla mph off'n WOT.

Wire nuts will eventually fail also, but are probably better than the bullets.

hope it helps
John

 

[toonin22]

Re: undecided need help

thank you for the input. and it is my personal belief that it should be soldered if anything especially if you have to do it again. but i am not him. its his money. he will eventually take my advice just a matter of time. thanks again really good info.