History:

The small wire on my solenoid (Guessing coming from Fender-mounted solenoid?) would sometimes detach from my starter/solenoid (B in the diagram below) after a bumpy ride. I'd go to start up the truck, nothing would happen, sure enough, the wire had slipped off and I'd put it back on and I'd be good to go again. The other day this happened, when I put the wire back on, the truck started up but the starter motor sounded like it struggled briefly to get the truck going. When I got back home and parked in the driveway, the truck would no longer start.

Now I'm getting a click when I try and start the truck.

I cleaned battery terminals, checked the voltage, charged the battery. I'm getting 12v on the fender-mounted solenoid terminals. I'm getting 12v on the multimeter checking terminal A (on the diagram below) and grounding on the body of the truck at the solenoid/starter.



I took off the starter motor, hooked up the 12v auto battery, positive to post A, negative to the starter motor body. Placed a jumper wire between B and A and the starter motor whirred to life. Seems to me the starter motor is OK.

I cleaned up all the terminals, tightened things down, put it back on the truck, still just a click.

Anyone know what's the next thing to diagnose here and how to go about finding the issue? Thanks.

 

You could crawl under the truck and try again jumping A to B. If you get a little click, bad solenoid. If you get a big click, more of a clunk, bad starter.

IDT you can just get a solenoid for these units, I think you have to replace the whole thing, in which case it does not matter which part is bad. I recommend DB Electrical on Amazon.

 

So would I disconnect the battery and then use jumper cables from the battery back to the solenoid like I did on the bench test?

 

I guess what I don't understand is that when I did the bench test and put 12v to post A and then jumped A to B the motor kicked in. When I bolted it on to the truck and hooked everything up, I'm reading 12v to post A, but jumping post A to B just gives a few sparks... What am I missing?

 

Run a jumper cable from the negative battery post to the block then try starting the engine. If it does crank over your cause is a bad ground connection.

 

I did this, no luck.

I measured Neg battery terminal to ground bolt on starter, on key turn it gives me 0.03v, positive terminal to that A post on starter gives 0v.

When I do turn the key I do hear a whirr for a second or two, I thought it was the fuel pump engaging, But having done all these measurements and still no luck I think it's possible it might be the starter turning (as it does on the bench test) but not popping out to engage (which it does, right?) ... I'll have to get someone to help me turn the key so I can actually listen properly to where the noise is coming from the rear or from the starter at the front.

 

After getting some help, it was the fuel pump making a sound, not the starter, still no luck...