Hello all. I'd like to say thanx to all the folks out there that take their precious time to respond and help others with their problems. This is a great site & source of info!!

Here's the problem I'm having with my '82 300D:
My starter occasionally will kick out & spin freely but will not engage the engine's flywheel at all. It will do this once or twice, then it will engage & start normally. I figured maybe the solenoid was sticking so I removed & disassembled the solenoid & cleaned & honed the cylinder wall & reassembled. Worked Ok for a while, then came back. I then replaced the starter/solenoid assy with a reman'd unit by ac-Delco. Then, what do you know, the problem still exists!! Upon removal of the starter, I looked at the flywheel teeth & in several places around the flywheel I did notice some wear on the "leading edge" of the teeth but certainly none were missing or chipped. What in the world is going on? Any ideas or suggestions would be greatly appreciated!! Thanx. Bill

Did you replace the starter or just the solenoid assembly? If the starter, you got a bad rebuild. It happens. If the solenoid only, well, you probably would have been better off replacing the starter. Hurt my wallet, but I went with a MB rebuilt starter when I had to do the starter last March on daughters '83 300D. Hers had the same problem. Hasn't missed a beat since. If you did the starter, is it still under some sort of warranty? Man, I hate taking that thing out on the 5cyl turbos.

Yeah, I replaced the starter which came with the solenoid. But I don't understand what's going wrong with the starter. I wish I had some sort of theory I could take with me when I return the part. I've already called the parts store & they told me they would do a bench check & if it kicked out & turned they would not take it back (& of course it will bench check). I don't doubt at all that it's a bad rebuild - just wish I knew exactly what the starter's problem is. Beyond that, you said you ended up with a rebuilt MB unit & it's been a good one? I've heard others say the Fastlane starters are good also (?). Did you say your daughter's car had this exact same problem? Yeah, I really don't want to replace this starter too many more times. Not fun.

when the starter "whirrers", then voltage is enabling the motor (of the STARTER) to spin freely...if the SOLENOID is energised, then the pinion gear SHOULD engage the teeth of the flywheel on the (diesel) engine. however, the solenoid may be only partially (or not at all) engaging the flywheel. if the voltage from the RELAY is a good STRONG 12vdc, then possibly the SOLENOID is at fault....if the "whirring" is NOT actually the starter motor spinning (at speed), perhaps there is another difficulty. Please be Sure that All of the electrical connections are free of CORROSION.....i am NOT SURE, but i think that your RELAY may not have good contacts. only my opinion. please consider all other opinions. good luck.>>...p.s. often, the solenoid will stick and not engage AND OR release completely when WORN and or when COLD.(not GEORGIA cold, if you catch my drift) best wishes always, spo.

Thanx for your advice, spo. Yes, I am positive that the pinion gear is being spun by the starter & that's my "whining" sound. But what doesn't make sense is that the actual starter relay contacts aren't "made" until the travel is such that the flywheel SHOULD be engaged by the pinion gear, atleast that's the idea. I called the parts store & they told me the "reman'd" AC-Delco unit would have had all its internal parts REPLACED with new. The only used part remaining was the housing so I can't figure what could be wrong. I still have the old one I removed - maybe I'll take apart the solenoid again to see what I can find out. And yes, all my elec connections are good & battery strong. Once engaged, the starter turns the engine well.

Yeah, my daughter's car made the whirring sound but no start. Happened a couple of times and she hollered about it. I verified the problem and just ordered the part. Don't want her stranded anywhere.
I believe the bendix gear is not extending all the way out. Bench test is worthless for this kind of diagnostic. Does not duplicate the conditions the starter is trying to operate with.
That said, let me add a word of caution: if I was about to get into a spitting match with the parts guy over this, I would make one more check. I would remove the started and mark the ring gear on the flywheel. Then I would watch the gear very carefully while an assistant rotated the engine all the way around. Just to make sure that there were no teeth missing. A small bit of chewing on the edges is one thing. A missing tooth is another thing entirely.

The problem that you describe is usually the starter drive. It has a oneway clutch design to keep from over revving the starter when the engine starts. If this clutch slips you will have this problem. Starter sound, but no start. Just replace the starter drive in the old one and ask for a refund on the defective new one. Jeff

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1971 R600 Mack toterhome (SuperDawg)
99 NU-WA Snowbird 34+2 SE 102 5er
If it's not diesel, it's not in my stable!
53 F100 617.951/auto
95 Dodge 3500 Cummins/5 speed service truck

Is this starter clutch more inclined to fail in cold weather? On my car, starting last winter, it occasionally misses a start. Seldom does it do this more than once, and then it catches fine and starts. It worked fine during the summer months.

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1976 240D
1987 560SL
2007 E320 Bluetec
1998 C280 (now son’s car)
1982 240D Manual - Sold

This problem seems to show up more in cold weather. Probably because grease in starter drive is old and hard.
Jeff

__________________
1971 R600 Mack toterhome (SuperDawg)
99 NU-WA Snowbird 34+2 SE 102 5er
If it's not diesel, it's not in my stable!
53 F100 617.951/auto
95 Dodge 3500 Cummins/5 speed service truck

I had this exact problem once in one of my old cars that had a Bosch starter. The starter spun but wouldn't turn the engine over. It was a clutch problem exactly as described above. It happened infrequently at first but got worse pretty rapidly. I found a specialty automotive electric shop that diagnosed it and replaced the clutch. It completely cured the problem.

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LRG
1987 300D Turbo 175K
2006 Toyota Prius, efficent but no soul
1985 300 TDT(130K miles of trouble free motoring)now sold

If anyone has any experience changing this starter clutch or where it can be purchased, I would be interested in a few more details.

Thanks.

__________________
1976 240D
1987 560SL
2007 E320 Bluetec
1998 C280 (now son’s car)
1982 240D Manual - Sold

Hi, all. It's Bill again - thread starter. (No pun intended).
Starter clutch - wow, huh. Well, since I'd already purchased my AC-Delco reman (which apparently was a bad rebuild as previously suggested & oddly enough had the same failure as my original problem - go figure) all I could do was return it for an exchange with a reman'd "World Class" Bosch. Installed it yesterday - so far, so good.
This starter clutch - is this something that a DIY can generally do or would a special electrical/overhaul place have to do it? I, too am curious about this for future reference.
But as for my starter problem, knock on wood, I think this new starter did the trick. Thanx very much for all the help & advice.