How is the starter grounded?

[Jay87]

Oh, also... what should happen if I disconnect the wire from terminal 50?

[Jaxx_]

Have you troubleshooted the solenoid?

If you really want to go crazy, jump the starter by bypassing the solenoid. If it turns you know what the issue is. If it doesn't, then start worrying about your ground.

And don't catch anything on fire or shock yourself.

[StereoInstaller1]

What are you using to test voltage with? You really should not be using a meter of any kind, you should be using a test light.

A meter can see voltages when there isn't enough current to actually trigger things, but a light bulb will show enough load to be a "real" reading.

Test that starter wire when disconnected with a test light first.

You know this is gonna be some dumb little thing, right?

[Jay87]

I guess thats a good point - I've been using a digital multimeter. And yeah, its bound to be something dumb.

I tried to bypass the solenoid by taking the large lead from the junction block and touching it to the bolt on the solenoid where the field winding strap goes... if this is not correct, then the positive connection from the solenoid to the starter must be internal to the assembly body. When I did this, the motor did not turn. I'm beginning to think I need to test my battery, even though everything else seems to run fine (dash lights, headlights at normal intensity).

I will get my hands on a test light and make sure I enough current to light it at those terminals.

I'll see what I can do about not lighting fires and getting electrocuted. You can worry if I dont post back. By the way, StereoInstaller, I can't stop watching you signature :-P

[Jay87]

It IS the effing ground! I dont know why, or how it would have spontaneously lost ground and failed to crank, but I grounded one of the mounting posts on the back of the starter body to my strut tower with a jumper cable and it cranks! It seems a tad slow at first, not sure why, almost like my ground with the aligator clips wasnt quite good enough or something. So I can make the car start now, and feel like I can fix this with a beefy grounding strap.

But, what could have happened all of a sudden to kill the ground? Ive hypothesized before that losing the starter mounting bracket to the block might have done it, but I dont know if the car had it previously.

I've made sure the starter is mounted tightly to the flywheel housing, and that the contacting surfaces are clean. Is there a grounding strap from the tranny to the frame that I could be missing, or is the flywheel housing grounded by virtue of its bolted connection to the block?

I'm glad to have found a fix, but now I need to understand! (Its the engineer in me I guess).

[StereoInstaller1]

I bet that bracket is the issue...

[Jay87]

Nope, looks like it was my old shitty grounding strap. Pulled the strap off the car that goes from the oil pan to the frame, and cleaned both ends and mounting surfaces with a steel wire brush.

Starter cranked right over. Probably I should replace this strap entirely...:roll:

Thanks for all the help diagnosing!

[StereoInstaller1]

Holy crap!