M35A2 starting issues

[Jerro2]

When attempting to start my truck push the start button the buzzer stops momentarily then starts back up, but the truck doesn't attempt to start. I've checked and replaced the battery terminals and the condition stays the same. Can anyone tell me if starters stop working without warning, just like Chevrolet starters do? Or any other suggestions would be welcome.

Thanks

 

[Elk1111]

How old are the batteries?

 

[pitpawten]

Work your way through the system:

1. Batteries full 12v each at terminals
2. Batteries full 24v at terminals when connected
3. 24v continuously at both ends of wire #7
4. 24v at wire #3 when start button depressed

If 1, 2 or 3 are no check batteries, terminals and ground

If all are yes but 4 is no, likely bad start switch, jumper wires #7 and #18 to see if you get a crank.

If all are yes, you can supply 24v directly to the 2nd stud on the solenoid (circled in pic) to see if you get a crank. If no likely bad starter, but that's the last option.

 

[G744]

The buzzer is just a "low air pressure" warning.

It will buzz until sufficient air (about 80 psi) is present.

 

[art]

I had a similar problem,
Check the battery ground wire that attaches to the frame.
Located above the batteries on the frame.
My cables were loose from sliding the batteries in and out.

 

[ToddJK]

Pitpawten had it right, only thing I'd add, check the battery wires, if you can see copper, check for any corrosion, sometimes you have to peel the insulation back a little to make sure. I had that issue not long ago and when I attempted to start the deuce, it just clicked then I had nothing for a moment and the power came back. My first thought was a loose terminal but one of the cables was full of corrosion so I replaced all the battery terminals and one of the cables.

 

[M35fan]

I cannot add to the good advice above, except:

My truck acted exactly the same way once. For me, it turned out to be weak batteries. They were each showing ~12.5V on my meter, but when I took them to Oriellys for a load test, they didn't have enough amps. I put two brand new batteries in, and she fired up instantly. Good luck!

 

[pitpawten]

I'll also add that I had a very similar symptom on my truck which turned out that the starter solenoid was on its way out and eventually welded itself open which eventually melted out a battery.

So I don't think there's a shortcut for checking each piece independently, which really isn't that big of a deal.

 

[72m35a2]

Chevy starters ?? What like a thousand years ago
On mine. Mice chewed me wires to solenoid under hood.

 

[Jerro2]

How old are the batteries?

Batteries are 2 years old, both hold full charge still.

 

[Jerro2]

Chevy starters ?? What like a thousand years ago
On mine. Mice chewed me wires to solenoid under hood.

Yes, Chevrolet starters are notorious for just stop working with no warning. I've been checking all my wiring, but haven't found anything along the lines of what you experienced, yet.

 

[Jerro2]

The buzzer is just a "low air pressure" warning.

It will buzz until sufficient air (about 80 psi) is present.

Yes, I'm well aware of what the buzzer is for. Thanks.

 

[Jerro2]

I had a similar problem,
Check the battery ground wire that attaches to the frame.
Located above the batteries on the frame.
My cables were loose from sliding the batteries in and out.

I checked that as well. I've been checking all my connections, since I thought it might be a bad wire connection. I guess I didn't fashion my problem very well when I asked for assistance, I'll do better next time.

 

[Jerro2]

Work your way through the system:

1. Batteries full 12v each at terminals
2. Batteries full 24v at terminals when connected
3. 24v continuously at both ends of wire #7
4. 24v at wire #3 when start button depressed

If 1, 2 or 3 are no check batteries, terminals and ground

If all are yes but 4 is no, likely bad start switch, jumper wires #7 and #18 to see if you get a crank.

If all are yes, you can supply 24v directly to the 2nd stud on the solenoid (circled in pic) to see if you get a crank. If no likely bad starter, but that's the last option.

1) yes, 2) yes the remaining ones I'll check. Thanks for the help.

 

[Jerro2]

Pitpawten had it right, only thing I'd add, check the battery wires, if you can see copper, check for any corrosion, sometimes you have to peel the insulation back a little to make sure. I had that issue not long ago and when I attempted to start the deuce, it just clicked then I had nothing for a moment and the power came back. My first thought was a loose terminal but one of the cables was full of corrosion so I replaced all the battery terminals and one of the cables.

Okay, yes I replaced both terminals due to being unable to tighten them enough to make good contact with the battery post. I didn't notice any corrosion on either cable, but I will check. This just happened all of a sudden. One moment the truck will start the next time I tried it the low pressure buzz pressed the started button everything went silent then the buzz started again. Thanks.

 

[72m35a2]

Off topic. Chevy starters on gen 1 blocks fail because of heat. Normally when headers are added

for ur problem. Just go back to basics. Start where u have power/ voltage. Then check down stream till you find where y don’t have power
If u have full power to the starter and solenoid then starter is likely bad or something is overloaded the circuit