...I had a corroded battery cable, waay down inside under the rubber.
Sometimes it would work, sometimes it would overheat and not work.
I figured out that if I loosened the battery cables and wiggled everything
it would get to the point I could start it. After I replaced the cables I cut
them all apart and found the problem. The wires were mostly green
powder.
Cool one, Ryan.
Know this:
You could've found the problem the first time it sounded -weak- if you
would've put a meter to the system and traced down the partial open
circuit. You would've never broke down even one time from it.
Believe it?
Also if you would've put a little motor oil on the connections when new
and did it in such a way that the motor oil ran in under the insulation a
little, that set of battery cables would still be working good.
Believe it?
Just a 1/4 teaspoon on each one when you change the engine oil. That
don't sound too hard to do does it?
Replaced the original (really-small! 8 gauge?) battery cables off my '75
F150 at 150k miles in the mid 90's. They were still good, just my buddy
wanted me to replace 'em because they looked so little an' Micky Mouse!
Micky Mouse or not, they still worked good as new because they'd never
corroded.
-----------------------------------
See that little cable clamp at the rear of the big clamp?
Found -lots- of those too open to operate the starter.
One day found both of them bad on the same battery. LOL
The coolest part of it for me was she was at the scrap yard and all the
guys there (workers and customers) were voicing an opinion on what
was causing the trouble. Many of them were agreeing with each other
and "patting each other on the back" for their diagnosis too. LOL
Not a single one mentioned the little clamps because they looked-clean
they had to be good, see? ...take a guess who walked over with a cheap
analog meter and found the trouble with no-guessing and quicker than
it takes to read this post. xD
Using a meter to find electrical trouble really does work.
Believe it?
Steve83's got a write up showing how to solder cables to get rid of
those sorry things.
The little clamp looks to be too small, but I've always wondered if it
wouldn't work good if the plate and bolts were bronze and kept oily.
Alvin in AZ
ps-
BTW, this is a starter relay...
http://www.panix.com/~alvinj/file12/starterRelay.jpg
That round thing on the side of the starter motor is a starter solenoid...
http://www.panix.com/~alvinj/file12/starterDelco.jpg
...it could be called a "Delco" I guess? It was invented by Delco.
It doesn't have to have a starter relay because it can be controlled by
a light-duty ignition switch. The positive battery cable goes directly to
the big terminal there on the starter solenoid.
These Ford starters need a starter relay because they don't have the
starter solenoid on 'em...
http://www.panix.com/~alvinj/file12/starters351w.jpg
...that's a manual transmission starter on the left.