Originally Posted by carpe_diem
hello, I wasn't sure where to put this post. O.k., last month I think, either myself or my wife had posted a question as to what motor we have in our '83 oldsmobile delta 88. Well I want to thank the person for helping us. And it is indeed a Buick 307..Regal to be exact. Last month we had a horrible time with alternators....kept burning them up and I didn't understand as to why, well tracing the alt. wire back it led to the starter and it was burnt, along with the distributor, and ignition wires. By then, I was ready to scream. So, I pull the starter to gain clear access to the connectors, that's when I found a small metal plate affixed to the block.....come to find out it was a reman. block in 1995. So I WAS at least pleased to find that It also has info. on the bore and the main and rod bearings. Anyhow after pulling the starter, I go to have it tested, one place said it was bad and another said good so I'm thinking what the
. I asked a friend of mine and he said that there might be some bad windings or something. I took it apart and found that the large terminals on the solenoid were pitted and burnt. I'm just wondering if this could have been the root of all this grief? The car seems to be running fine now. I hope that some of this info may be of some help to someone.
Burnt wires are a result of a higher current drain than the wires are designed for. This overheats them and melts the insulation, in bad cases the wire itself. This is usually the result of a short or some item pulling more current than the wire is designed for, the manufacturers seldom get this wrong. These circuits with the possible exception of the starter are protected with fuses which certainly should blow before the wire gets hot enough to melt insulation.
Burnt contactors inside the solenoid may or may not be meaningful. The heavy current it switches to the starter has a tendency to burn these given enough time. On the other hand a starter with an internal short will pull abnormal amounts of current and burn the contacts sooner rather than later.
I think the alternator wire going to the starter solenoid is a bit strange. One could connect with the battery's positive side there, where the power cable attaches to the solenoid's power lug. But typically the alternator wire attaches to the battery at the positive post, this just saves the OEM a couple feet of wire when the battery is under the hood. The way it's wired is functionally fine but you need to be sure the routing keeps wires away from the hot exhaust system.
Why ignition wires and distributor would be burnt, I don't know they should be fuse protected and are not in the power charging circuit. As for the alternator, if there's a short, which could be internal to the battery, that isn't fused, the alternator will rise to the occasion and try to supply the demanded power till the smoke leaks out of it.