Intermittent no start 1981 240D

[sun tortise]

Replaced my starter, because on the old one (a rebuilt from Pep Boys) apparently the solenoid got stuck in the "engaged" position and ground it's little teeth off. The unit i replace it with was rebuilt by an old timey rebuild guy, and for a few days worked fine, hot or cold. Then it just quit. Got home thanks to a push start.

The next day, with the car fully cooled down, it started just fine. But after i drove about 5 miles, it would not crank again. Fortunately, i parked on a hill. When i got home, i checked the battery, it was at 12.85 volts. Would not crank. Also tried pulling the glow plug connectors. Hit the solenoid with some "Freeze-it" to cool it down, also banged on it with my special solenoid whacking tool, and it STILL would not crank. Checked and re polished the battery connectors and the chassis connection from the battery. I had also polished the battery cable connector at the starter end. Jumping from the starter terminal to the solenoid terminal with a screwdriver elicits a spark, but no action.

Any ideas? I'm thinking the solenoid is iffy and the old timey rebuild guy (now out of business and probably deceased), bench tested it, (which i also did before installing it) and the solenoid worked fine. Is replacing the solenoid worth the effort, or should i just get a whole new starter. Or am i overlooking some other possible cause of the problem?

Thanks!

[Sugar Bear]

The heavy positive battery lead should always read battery voltage at the solenoid. The little wire to the solenoid gets power in the crank position to close the solenoid which then essentially connects the heavy positive lead to the starter motor.

When it won't crank is there power to the small wire at the solenoid? If no the problem isn't starter/solenoid related. If there is power to the little wire check for power out of the solenoid to the starter motor. If no power out, the solenoid is bad, if power out and no crank the starter motor is bad.

If the solenoid is bad change it, if the starter motor is bad replace the assembly.

Hope this helps, good luck!!!

[Diesel911]

A typical troubleshooting step is to either use a jumper wire or a remote starter switch to the solenoid. If it cranks like that you have may have a neutral safety switch issue and or shifter busing issues.

How about your ground cables?

[sun tortise]

I connected the positive cable from the battery direct to the little solenoid wire via a screwdriver. There was a spark, but no action. So i think that eliminates the ignition switch as a problem. It is a standard (thank goddess, i was able to pop start it); so as far as i know, no neutral safety switch involved.

I guess when and if it quits raining, i will have to pull it. You will be able to hear me cussing all the way from upstate NY!

[Sugar Bear]

is there power to the starter motor from the solenoid when the little wire is energized? See post #2.

[sun tortise]

I did not check if there was power to the starter motor itself, but when i jumped the cable from the battery to the solenoid wire with a screw driver, there was a spark, indicating that the solenoid was drawing current, but it did not make any kind of noise that it would have if it were working correctly. But i did not actually check for 12 V on the starter motor itself, as i assumed that if the solenoid is not engaging, there would be no power to the starter motor. I could check that when it gets light out and stops raining.

[sun tortise]

So after the car cooled down fully overnight, i turned the key, and it cranked. Several times. So i let it warm up for about 20 minutes, turned it off, and it still would crank. But when it was about half cooled down, i tried again, and it would not crank.

Is this weird, or just "cranky"?