Sudden slow cranking problem
 

hi I have a 1998.5 dodge 2500 24v, a couple weeks ago my truck started cranking very slow out of no where's, even more so when it's colder outside.
I checked both battery's ( 31 series ) and they were holding at around 12.3v and load tested at just over 1000 cranking amps. When I engage the starter the voltd drop to around 10. Went and bought 2 new 27 series battery's and its cranked the same as before.
So I returned them and put the old ones back in.
I then started checking my leads, the positive going to the starter was a bit corroded so I replace the entire cable. And still the same slow crank, I then performed a drop test. I connected my meter to the positive terminal at the starter and the negative to the starter housing. Volts dropped to around 8, i then tried grounding the the starter housing directly to the battery's using another cable via starter bolt, and still slow cranking.
I went and grabbed the girlfriends car and tried boosting it to give it a little more juice and it didn't change a thing.

Im fresh out of ideas and don't want to go out and buy a starter and still have the slow cranking problem.

I read threw tons of threads and forums and tried everything that I could find.

Anybody have any ideas, cause I'm stumped.
thanks

Welcome to DTR! :welcome:

The steps you've taken look good so far. You may want to pull your starter out and inspect the solenoid contacts and possibly the brushes too.

The solenoid contacts wear out over time, though usually you get a no crank problem rather than a slow start.

Give this thread a read, it has a great write up and pictures on our starters.

https://www.dieseltruckresource.com/...tarter-141395/

I hope yours is still the original starter. They are very well built starters and fairly easily serviced. Don't replace it unless there isn't any other option. The auto parts store replacements are nowhere near the quality of the original.

I forgot to mention that the other day I heard some sparking noise as I was cranking it but couldn't figure out were it was coming from.
I'm gonna pull the starter this weekend and take a look at what's going on in there

thanks for the advice

For grins, also take off your serp. belt to make sure your alternator bearings did not seize.

That has happened more than once.

had the belt off last week to change the water pump and all pulley checked out good

Check the positive cable running across the front of the engine for shorting on a bolt. Also check there is a full size ground wine from the battery to the engine block, if it got left off the starter tries to ground through whatever it can.

12.3 volts is not great but bare minimum for a standing battery so do take that into account later on, even though your proved the cranking issue to not be battery related.

And yes, inspect the starter. If its OEM then simply replacing contacts and plunger may be all it needs. But.....if its unfortunately been replaced with an auto parts store unit then it could be dragging internally and just need to be replaced again. :thumbsup:

Did you do this after the hard start problem?

I had my Alternator bearing seize while idling and it killed the engine, turned so hard I burnt up the Starter.

Took the starter apart and the plunger and the contacts were paper thin. Change it and it's cranking faster then ever 👍🏼

Glad you got it fixed!