Author Topic: Sometimes she cranks... Sometimes she dont  (Read 3057 times)

Offline ChumminsCrew

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Sometimes she cranks... Sometimes she dont
« on: September 23, 2015, 12:37:03 PM »
Hey guys I'm new here and by the searching I've done I feel like I'm in the right place just have t found what I'm looking for yet. I've got a 90' model Cheyenne 3+3. I know it's later than 87 but to the best of my knowledge the one tons didn't change till 91. Either way I real hope someone cAn help me. In 2012 I set this truck up with a PPump cummins conversion and it's been the best investment yet. Now the problem at hand. Two weeks ago the starter crapped out. No big deal just go get a new one right? Well since doing that I got everything hooked up(which is still all factory wiring on the Chevy side and all it'll do is thump. I can jiggle the switch until my arm is dead and sometimes it'll start sometimes it won't. I kinda though the reman was a problem so I swapped it with a brand new one. Same thing! Pulled out my meter and went to work. Voltage was great everywhere. However when I would try to start it and it just thumped it'll only show about 3-4 volts at the exciter wire on the solenoid. If I take the wire off the post and try to start it shows 12+. At the times it thumps if I hold the ignition in the start position it drops the ammeter on the dash practically to nothing and the times it actually hits and starts its fine. Once it's running it reads around 15v. Way to high right? That's what I thought so I went back to testing. By now I've got my dash ripped apart and am testing through the ignition switch located down the steering column that the rod connects to from the key ignition and I've got a voltage drop of about 2 volts between there and the wire at the solenoid. Boom! Problem solved! Replaced the switch and hit the key same problem!!!!! Now I'm leaning towards fusable links. However the only one I have found is the on on the 8 gauge wire that goes to the 3/8 positive post of the starter. I had to leave for work so I haven't gotten to test anymore but could that be my entire problem or entirely irrelevant? I really appreciate any replies and any ideas yall can come up with. This truck is my bread and butter and really need to get it going again. Thanks in advance!

Josh
'90 3+3 Dually Cummins swapped 382hp/845tq
'82  K30 Prepping for 5.3/Nv4500/205

Offline Irish_Alley

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Re: Sometimes she cranks... Sometimes she dont
« Reply #1 on: September 23, 2015, 01:02:07 PM »
does the spindle kick out and make contact with the flywheel/flexplate?
i have a 91 v3500 that i just dropped a ve pump cummins into.
does it start if you jump the starter solenoid?
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline ChumminsCrew

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Re: Sometimes she cranks... Sometimes she dont
« Reply #2 on: September 23, 2015, 01:41:37 PM »
It sounds like it throws the plunger but doesn't have enough voltage to spin. Yeah it'll crank right up with a screwdriver across the posts. It seems like a ground issue or a wire somewhere coming loose that's taking to much load away causing the voltage drop. I've checked every ground under the hood and under the dash and everything is good.
'90 3+3 Dually Cummins swapped 382hp/845tq
'82  K30 Prepping for 5.3/Nv4500/205