AE92 Levin Smallport 4age alternator connector melted

[solitaire]

Hi,

As in description, just saw the grey plastic cap over the electric cable the connects to the alternator (or rather bolts to the alternator) is melted in a section, like one particular part underneath is very hot, will try to get picture when it is not raining,

anyone seen this before? any idea where to start troubleshooting.

only symptoms have been a slight burning smell which i thought was just 5 years of dust burning off, other than that the voltmeter shows 14v across the battery when it's at idle, no other issues to suggest something is wrong.

[matt dunn]

Wont be melted from current as there is next to no current through the connector,
so must be from external heat like from the exhaust manifold.

[solitaire]

Wont be melted from current as there is next to no current through the connector,
so must be from external heat like from the exhaust manifold.

It's a pretty beefy looking electrical cable, I thought they output like 70amps? (not challenging, just asking, I know you know your stuff!)

It's a pretty particular melt, i'll take a photo, it's on the intake side of the engine, i'll have a hunt for some heat sources.

[Grrrrrrr!]

70A distributor.. no..

70A alternator. now that would make sense.

[solitaire]

70A distributor.. no..

70A alternator. now that would make sense.

Aaarrrggghhh sorry massive typo, long day. I meant alternator, very sorry,- original post should be alternator, not distributor

[Stu-]

The reason the distributor wiring looks beefy is that its shielded which protects the trigger signal wiring from electrical interference. Actual voltage induced by the pickups is very low and current is minimal.

[solitaire]

updated OP to read alternator rather than distributor

sorry for confusion.

[matt dunn]

OK, yes have seen that, there will be a bad connection between the alternator and the lead.

Best thing to do it take both nuts off the alternator stud and replace them,
and file or sand the terminal until it is shiny, or replace it,

as it will only get worse and eventually burn the rectifier.

Have seen it a few times before.

[solitaire]

OK, yes have seen that, there will be a bad connection between the alternator and the lead.

Best thing to do it take both nuts off the alternator stud and replace them,
and file or sand the terminal until it is shiny, or replace it,

as it will only get worse and eventually burn the rectifier.

Have seen it a few times before.

Hmm, just replaced faulty rectifier

Will do that, many thanks for your help.

[matt dunn]

Hmm, just replaced faulty rectifier

Will do that, many thanks for your help.

The actual cause of the problem is usually due to the fact the nuts were not clean enough
or tight enough when put back together,
so if you have just done the rectifier either the problem was already there and may have burnt your last one,
or possibly has been caused during reassembly after replacing it.

[solitaire]

So the nut was effectively heat welded to the stud, which proceeded to snap off... which was not fun at 8.30pm when i had 90km return commute in the morning.

Managed to rangi the housing slightly to let me go lower on the snapped stud, sanded all the contact points back to shiny (they were filthy, really bad, no idea how i missed it) and reassembled.

Back up and running now, voltage across the battery at 1100rpm is 14.75V - sound ok? I'm not sure what it should really be, i think it's slightly up on what it was (14.5V from memory)