Burnt alternator plug.

[richard booth]

So my 1988 B2 which has been bulletproof for 230,000 failed to start for my wife. Went to get it and battery was dead, put a good battery in it and was good for a couple weeks then died again, got the alternator off and the rear plug w the two heavy gauge wires was badly burned up. Question is do I have to use a JY old plug or would it be advisable to make one? O.E rectangular plug is heavily insulated and literally turned to carbon. I looked all over but have not been able to find a new one, also searched the electrical threads but was not able to find one about this issue, any help appreciated.

 

[Ozwynn]

That plug is fire prone. I had the same issue on my 90 F150. The 2 black wires are the charge cables and they are not adequate to carry the load. The alternator itself is externally cooled and prone to heat stroke. I recommend a 130 amp 3g conversion. If your alternator is 7” from ear to ear you can use one from 93 Taurus or 95 Mustang... if it’s 8.25” you can use one from 92+ F150 with a 300 6cyl. If you have serpentine belt drive you will have to clearance the alternator bracket. If you have V belt then you will need your alternator pulley. I recommend using a 4 gauge charge cable with a 200a mega fuse. It took literally 10 min to convert the wiring and now I can run my lights, wipers, defroster, and 250w stereo and not drop below 14.6v

 

[4x4junkie]

I agree, a 3G alternator swap would be best course of action here. The 3G alt has a stud on the rear housing that the charging cable(s) attach to instead of the burn prone push-on connections you have on the OE (2G) setup.

If an alt swap isn't something you want to do, then the best I can suggest would be to get another (good) connector off a junkyard truck and clean it up as good as you can and use dielectric grease on it (however if the contacts on your alt have suffered any collateral damage, then chances are you're gonna be quickly replacing everything (again) anyway, so think hard about a 3G swap).

FWIW, the 95 amp 3G unit from a '95 E-150 or F-150 with the 300-I6 engine bolted directly in place of the stock unit on my 1990 2.9L. The pulley however will need swapped if you still have stock V-belts, and some (very minor) rewiring the electrical plug is needed.

Some info about alternator swaps is at right on this page:
http://www.therangerstation.com/tech_library/index-charging-ignition.shtml

 

[adsm08]

If you don't want to trust JY parts new replacements for that plug are available.

Last 2G alternator I bought even came with one.