Starter motor slipping? 300CE W124
 

Twice now in the past couple of weeks I noticed something on startup. I have a 1991 300CE, 120k. At the end of the startup right before I release the key, there is a “skidding” or “slipping” and as one member in his post put it “a not very pleasant grinding noise”. The first time the car did it, it was so brief, I wasn’t sure I even felt it. The second time it lasted longer and I definitely felt it. The kind of noise you hear from your car and you go “Uh oh”! I know nothing about starters so from the forum this is what I gather. The starter has a small pinion gear that may be damaged. The corresponding teeth on the flywheel gear may be damaged. The mechanism for retracting the pinion after startup may be faulty. So where do I start? Is removing, checking, overhauling a starter a DIY job?

TIA
Glenmore
1991 300CE

Glenmore,

Sounds like the pre-engage mechanism on the Starter motor is not retracting quickly enough.

If removing the starter motor is reasonably straightforward, it's certainly a DIY job, only involving a good clean and re-grease of the moving parts.

About as cheap a repair on a MB could be........

It could be the ring gear. I had a grinding/clacking noise, which sounded like the starter didn't stop spinning for a second or two after the car started. It turns out the ring gear was bent. I think it can get bent when you remove the transmission. Some techs try to pull the ring gear off with the transmission, but it is supposed to stay connected to the engine. Anyway, to get that replaced, you have to remove the transmission. I also had my starter replaced at the same time. I think it cost me $1000 or so total, parts and labor.

You can search ring gear, and there should be some other info...but just make sure that it's definately the problem before you replace it, as it's expensive and surely a headache.

Matt
94
e320
152k