Greetings all,

I have a 1997 Dodge Ram 2500 6 cyl, 12-valve, Cummins turbo with an intermittent starting problem.

My best girl uses this truck to transport her trailer and horse, (frequently), through our rural area and up mountains. Her getting stuck in the middle of nowhere would be a very bad thing indeed.

I spent all day Saturday in diagnostics and have pretty much decided the problem must be the starter solenoid, but I'm wondering if there is something I've overlooked.

First notice of trouble was refusal to turn the engine over. I had driven it maybe a mile-and-a-half and shut it off. 30-45 minutes later, it wouldn't start. Sometimes there was a click, sometimes no click. Turn the key to start and absolutely nothing happened. Jumpered to passenger-side battery from a friend's 2500 with same results. After a few minutes of trying, the engine finally started.

Drove it straight to my mechanic-friend at the farmer's coop. He started it several times in a row with no problem, (Isn't that always the case? Take it to a mechanic and it works fine for him).

The outside air temp was in the 60's--not hot, not cold.

As per the Haynes manual I have:

Pulled the key switch and checked all contact combinations up to 40 times with no continuity problems. Good.

Checked the starter relay and power going to relay. Good. (Is that one-inch-square relay really the only thing that provides power to the solenoid? I grew up with relays at least the size of a baby-food jar).

Checked the fuel pump fuse and power to it. Good.

Checked the park/neutral switch for proper continuity through multiple shifts. Good.

Cleaned battery terminals and lugged connectors. Batteries have proper fluid and voltage levels--about 12.75V with the engine off. Good.

Connecting voltmeter to battery posts shows about 14.3 volts when the engine is running. Good.

Checked cab console 10A engine fuse. Good.

Saw something vague about a possible fusible link, couldn't locate one. Is there one on this model?

After I put everything back together, it started right up. I let it idle for about 15 minutes, turned it off and tried to start again. *Click.* Nothing else happened. Tried again. It started. Several consecutive starting attempts revealed the same pattern: It would click and not start, then it would start, then wouldn't, then would. The fact that--when the problem first presented itself--sometimes there were *no* clicks when the key was turned, adds to my confusion.

When it's running--out on the road--it runs flawlessly: There are no secondary symptoms I have noticed.

Before I replace the starter, (am I correct in believing I cannot replace only the solenoid? Or could it be the starter and not the solenoid?), I would like to make sure I've checked everything else possible; I don't want to spend several hundred dollars when the problem is an eight-dollar part--I would end up sleeping in the barn. Have I missed something?

Any ideas or advice would be greatly appreciated.

TIA

Nathan

 

Sounds like you pretty much covered it. For starters though, I don't replace just the motor, or solenoid... they both hang out in the same environment, and when one fails, it is a pretty good bet that the other is not to far behind. Also, given that as a complete part, it really isn't that expensive..... just do the whole thing.

One thing you may want to look at before you spend your money though, is the wire that trips the relay, AT the starter... if it has greater than nine volts on it when you are actually trying to start the truck, bad starter. If not, then you need to find out WHY you don't have the voltage there.

Odds are very good though, that your starter is just old and tired, and in need of retirement.

Welcome to the Forums.

 

I just had a very similar problem and it wound up being my starter. Although my step has also had a similar problem but it was his ignition switch.

 

I would suspect the battery cables. Especially the negative. Next time it happens you can verify whether it is the battery cables or not by using a beefy set of jumper cables to bypass them. If it were me I'd try bypassing the negative cable first.

My old Fords over the years have notoriously eaten negative battery cables. On my mustang I finally solved the problem by going to a much larger guage battery cable than they give youy if you ask for an OEM replacement cable at the parts house. A brand new cable from ford or NAPA or whoever would last a couple years or so then suddenly one day the intermittent problems just return. Now there is a like a triple 0 monster cable or something completely ridiculous on there but haven't had it fail in like 13 years since I installed it.

I'm expecting a high compression diesel motor like a cummins will chew through even more cables than my gas Fords due to the amount of current the starter draws being so much.

Oh yes and BTW each of these battery cable failures I've had were intermittent. The jumper cable bypass technique saved me from walking many times until I realized I could overengineer the situation and fix it once and for all.

 

Well, if the barn is crowded and you really really really want to be sure it's not something else, you could mickey-mouse a (low current) 12V lamp in parallel with the solenoid, and place the lamp where you can see it. If the light comes on when the key is turned to start, but nothing else happens (no click, no crank) then at least the solenoid is failed. If the lamp doesn't come on, something is keeping coil voltage away from the solenoid.

I'd replace the starter and solenoid as a unit. There's no law that says you have to, but it'll remove the starter from your list of things to worry about. I kinda figure that if your SO would put you out with the horses for spending money unnecessarily, she'd put you out with the cattle if she gets stranded because the starter lets go in November.

 

Thank you all for your helpful ideas--I checked out everything you suggested.

Better than 9v going to the solenoid at all attempts--connection on the starter itself reads 12.52 volts. Main battery connections are all good. Cables all good.

Had the problem described in initial post at first-try today. Let the engine warm up to operating temp and checked again. Couldn't for the life of me get the problem to rear it's ugly head, but a couple of times I did get that gut-wrenching screech that says the bendix isn't fully engaging with the flywheel. That's a brand-new symptom as of today.

So. Mr. Dodge is getting a new starter and solenoid.

Thank you all again for your help.

Nathan

 

Glad to read you found the problem, and thanks for the follow-up!