Starter relays keep failing

[Auser]

So, my 1984 aspencade has gone through 2 starter relays in matters of 2 to 3 starts before they both failed. The original relay failed because the wire going to it melted in half. I think I have it wired correctly, but must not. All the electronics work correctly, starts a couple of times, then the starting half of it fails, while everything else works correctly.
Any ideas?

[Rambozo]

Measure the starting current. Probably a bad starter drawing way too much current.

[Auser]

I'll make sure to do that

[Auser]

So, since the relay won't make the starter work, am I going to have to jump it via relay to measure the starter and use the multimeter on the wire going to the starter connection on the relay?

[Rambozo]

To measure that amount of current, you will need a large shunt or a DC clamp on ammeter. A typical multimeter will not do more than 10 amps, the starter could be over 100 amps.

[Auser]

Oh, that sucks. I'll see what I can do about that.

[WingAdmin]

It could be a bad starter drawing too much current. It could also be resistance in a cable or connector. If oxidation or something has caused some resistance - even a small amount of resistance - in a cable, or where a connector is clamped onto the end of a cable, or between a connector and a terminal - basically anywhere in the power chain, when you pull current through it, it will heat up wherever the resistance is encountered. With the huge amount of current being pulled, that heat will build up very quickly.

This is exactly why the "three yellow wire" stator connector melts - the terminals in the connector oxidize and develop resistance, lots of current gets pulled from the stator, the connectors heat up enough to melt the connector.

[Rednaxs60]

I would recommend a refurb of the starter. These starters have a lot of crud inside from the brushes and need to be cleaned. if you don't want to do it yourself, take to an auto electric shop that does starter/alternator work. An auto electric shop should be able to do this work in a few hours. The other benefit to using an auto electric shop is that the shop will have the tools to change the starter bearings if needs be. The OEM starter can be rebuilt a few times, and the expense is generally less than an aftermarket starter.

[Auser]

Thank you for all the info I'll definitely be taking a look at the starter. If the bearings do need replaced I'll take it somewhere, but otherwise I'm really trying not to take any part of it to a shop, because I like working on it even though it's a pain sometimes.

[Rednaxs60]

Here are some pics of the starter disassembled. There is a cover locating pin, quite small, don't lose it. Internal wiring may be hard, brittle, needs to be moved out of the way when removing the armature.

Good luck.