another battery / starter issue

[riffman12]

Thanks for the replies guys. I'm starting to think the issue is a loose connection somewhere because the issue doesn't seem to happen on warm days. As one of you said, heat causes expansion which forms a stronger connection

I'm in the UK at the moment but will be investigating when I'm back next week.

What are the most likely connections to check? The battery terminals look fine.

 

[TheDurk]

Thanks for the replies guys. I'm starting to think the issue is a loose connection somewhere because the issue doesn't seem to happen on warm days. As one of you said, heat causes expansion which forms a stronger connection

I'm in the UK at the moment but will be investigating when I'm back next week.

What are the most likely connections to check? The battery terminals look fine.

Yeah, that ain't good enough. If I have your situation, no matter how they look, I will pull both terminals, use a battery brush on posts and terminals, coat with Vaseline (not dielectric grease in this one case) and retighten. This is routine PM should be done every two or three years or so anyway. Then pull fender ground, sandpaper terminal and surface, and retighten. Don't look, just do it before testing anything else.

Also check carefully attachment of terminal to cable and all along the insulation for any bubbling on the outside. This is a sign of bad corrosion underneath.

That done, the only other connection that will overheat if poor is the large starter lug to battery positive cable. That's a fun one to get to. All the other connections are low-current in the control circuit and I would be surprised if they would have that behavior. So once you have done the above, time to pull the starter. First verify you have good 12V+ at the small lug when the key is turned. That will rule out the control circuit.

 

[riffman12]

Yeah, that ain't good enough. If I have your situation, no matter how they look, I will pull both terminals, use a battery brush on posts and terminals, coat with Vaseline (not dielectric grease in this one case) and retighten. This is routine PM should be done every two or three years or so anyway. Then pull fender ground, sandpaper terminal and surface, and retighten. Don't look, just do it before testing anything else.

Also check carefully attachment of terminal to cable and all along the insulation for any bubbling on the outside. This is a sign of bad corrosion underneath.

That done, the only other connection that will overheat if poor is the large starter lug to battery positive cable. That's a fun one to get to. All the other connections are low-current in the control circuit and I would be surprised if they would have that behavior. So once you have done the above, time to pull the starter. First verify you have good 12V+ at the small lug when the key is turned. That will rule out the control circuit.

great thanks for this. I got back last night and will be hopefully getting some time this week to start diagnosing using the tips you've all provided.

One extra bit of info: last night and this morning, it was reeeeally cold out. The 4runner cranked to life on its first try both times with zero issues. Usually cold weather caused the most problems, but now I'm wondering if it was related to the heavy rainfall we were having when I made the thread.

Is there anything that rainwater would be doing that could cause these sporadic starter motor issues? Perhaps it's getting a relay or a fuse wet or something?

 

[riffman12]

just to update anyone who has similar problems:

I haven't had much time recently to work on the truck. It's also dark out every time I get back from work now, so I took it to my local mechanic.

They tested the starter and confirmed it was bad. Replaced it with a reman. Denso unit. I don't know if it was the contacts or something more serious with the starter, but it's nice knowing the whole unit is good now.

 

[IBallEngineer]

just to update anyone who has similar problems:

I haven't had much time recently to work on the truck. It's also dark out every time I get back from work now, so I took it to my local mechanic.

They tested the starter and confirmed it was bad. Replaced it with a reman. Denso unit. I don't know if it was the contacts or something more serious with the starter, but it's nice knowing the whole unit is good now.

I guess I can't say I told you so, because guessing doesn't count!
And you swapped it out completely? Say it ain't so!! hehe