Cummins Diesel Forum banner

Help with starting issues

612 Views 4 Replies 4 Participants Last post by  tobylou8
Hello,

This is my first post here, so I hope it's a good one. I'll try to make it short as possible.

The issue I'm having is that the truck is acting like it's got a dead battery upon initial start when it's "cold". it'll crank very very slowly upon initial startup attempts, and after a few seconds it'll refuse to turn at all. It's been in the 40-50s here so I dont think it's that cold. Once the truck runs for even a minute or two, I can shut it off and it will turn over hard like it normally would, and start right up without hesitation.

I've tried everything I can think of to solve the issue. Here's a list of the mods I've done/tried to get this thing to start.

2/0 Cables with high quality lugs for both ground and starter
Additional 2ga grounding system that connects directly to 14 different locations on the truck
battery cut off switch to ensure there's no draw when the truck is shut off
every battery known to exist..... i've been through stock batteries, heavy truck batteries, and now im rocking a dual 6TAGM battery set up with approximately 2450CCA capacity (those batteries aren't cheap)
Starter and alternator are brand new and have been removed from the truck twice in the last 4 months to ensure they are still functioning properly.


I've bypassed the C/O switch to make sure that's not the issue, and checked the specs on it's current draw capacity to ensure it's able to handle the throughput. so that seems fine.

Like I said, I can not for the life of me figure out what the heck is going on with this thing. It's driving me crazy and it's such an inconvenience just to get going in the mornings. I've resorted to carrying around another battery in the bed of the truck so i can jump start it from that. once it starts, it's fine to continue to start for the rest of the day. I know it's not a battery issue that's causing the problem.

The strange thing is that it only happens after it's sat overnight. if i fire it up, run around for a minute and then park it for 4-6 hours, it usually starts right back up without hesitation.

Any assistance on this problem would be greatly appreciated,

Thank you,
Matt
See less See more
  • Wow
Reactions: 1
1 - 5 of 5 Posts
Is it an automatic or manual transmission? How does it run while warming up?
Is the engine stock?

Does the starter have LarryB's heavy duty contacts in it?

  • Like
Reactions: 1
Yeah sounds like a starter issue more then anything else....even though it might be "new" doesn't mean it's a good unit. I've gone trough multiple units, starter, alternators etc that were "new" and were junk right out of the box.

Things can test fine on the bench, but once they are actually put under "load" they will fail of perform poorly.
  • Like
Reactions: 1
Yeah sounds like a starter issue more then anything else....even though it might be "new" doesn't mean it's a good unit. I've gone trough multiple units, starter, alternators etc that were "new" and were junk right out of the box.

Things can test fine on the bench, but once they are actually put under "load" they will fail of perform poorly.
I went through three alternators in a year!!! Finally figured out on the Remans, all they do is change the brushes. If the rectifier diode is within "specs", it stays. I started testing them in the store for a/c leakage and none of them passed. Finally got a PAperformance 1 wire and ended most of my electrical issues.
  • Like
Reactions: 1
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top