Starter not even turning over intermittently
 

I was just on a long drive with my 1984 300SD and I stopped for fuel after about 4 hours driving. Temperature was in the 40s to 50s. After fueling the car would not start. The battery is new and all other electrical was functioning. I checked the fuse box, and they all seemed fine. The glow plug light went on and cycled through, but when I turned it nada. It was if the transmission was put in gear not park or neutral. I crashed the night and the next day the car started no problem in similar temperatures. I then ran the car for about an hour and turned it off, and it started again. Any thoughts? I could not find a similar post, but if you know of one. I would love to see it.

possibly a bad coil in the starter solenoid. intermittent electrical problems are pretty hard to track down... im sure as the problem get worse, you'll be able to pin point it easier.

good luck

Could be a bad starter. Does anyone know if the SD has a junction box like the D that allows a person to bypass the ignition circuit and jump the starter under the hood? Look for a junction box on the right inner fender (?). If you have it, jump terminals 1 and 3 to engage the starter.

That is good to know on how to short. I saw this post:

http://www.peachparts.com/shopforum/tech-help/19947-procedure-replacing-neutral-safety-switch-126-chassis.html

which indicates a similar problem. Thanks.

I'm suspecting the engine-chassis ground strap. I went through this same scenario a few years ago and found that the bracket, the strap was attached to, was loose. I changed a perfectly good starter out, in the parking lot on a hot Texas summer afternoon, before I found out the real problem.

Thanks Sam. What does that grounding strap look like?

I had a similar problem. After checking the ground strap, power from ignition, and the battery I decided to pull the starter and check it out on the bench. I have a manual transmission so I don't have to worry about the neutral safety switch. On the bench I was able to find a cold solder joint where the primary coil in the solenoid is grounded through the motor itself. Its just the solder joint just above the 17mm nut that the motor power comes from on the solenoid. I cleaned it us with a wire brush, added a bit of flux and resoldered it. Its good to go now and has not given me any trouble since.

I got a lot to look at. Thanks for the ideas

There is only one and it's BIG, about 00ga. and near the starter.

Next time it wont crank, run jumper from hot battery terminal to starter hot input, that will isolate starter.

Im betting bad starter, and you are lucky enough to at least get some warning that its going. Replace now or beware.

It seems that the car starting intermittently indicates the solenoid and or Neutral Safety switch. Thanks everyone.

Check the neutral safety switch, possibly your shift linkage bushings, they're known to do this.

possibly a worn out starter...mine just died this weekend. last few starts were kinda like a weak battery...then after about a dozen weak starts over 2-3 days it finally quit...starter clicks but no rotation. jumping did nothing and voltmeter shows a stron battery....pulled and tested, tested "ok" on the bench but we could see it turning real slow and very weak...enough to pass bench test but it's practically dead...

classic hot starter problem...heat increases the electical resistance...makes it hard for the starter to run...that's why letting the car sit and cool down sometimes helps...when copper gets old and corroded the resistance goes up over time...eventually needing to be rebuilt....

i'm guessing that was my problem and might be similar to your problem.

I have the hot starter problem from time to time.. When I'm not so lazy I'll replace it. Probably have to strand me somewhere to motivate me.

I have the same issue. I have never been stranded though. I get my car jack out and a couple hard bangs on the starter and starts right up.