Starter Question: 450 SLC - PeachParts Mercedes-Benz Forum

kbunting · #1 03-19-2006, 08:41 PM

My 1979 450 SLC occasionally would make a grinding noise when attempting to start the car which sounded like the drive gear on the starter was not engaging the flywheel but merely grinding against it. After several tries, it would start perfectly. I removed and replaced the starter and starter drive (called a Bendix drive on U S cars, not sure what Mercedes calls it) and the problem is still there. Often it will start and engage perfectly on the first try. Other times it will grind and require several grinding attempts before the starter engages properly and turns the engine over as it should.
I have owned the car for 14 years and this has only happened in the last year or so.
Any suggestions on what could be the cause?
Is the "reach" or extension of the starter drive gear adjustable? (How far the starter gear slides forward when activated) In other words, is it not contacting the flywheel teeth or going beyond them?
Can the flywheel teeth be inspected from underneath the car to determine if there is excessive wear or a broken tooth on the flywheel gear teeth?
Thank you in advance for any suggestions or thoughts.
Kurt

t walgamuth · #2 03-19-2006, 09:56 PM

ring gear can be checked from the bottom. you should have a flat metal plate that will come off the bottom under the ring gear so that you can inspect it.

it seems unlikely to be an electrical problem to me.

tom w

kbunting · #3 03-19-2006, 10:15 PM

Tom,
Thanks for the input.
Am I correct in assuming that you think it is a problem with the ring gear on the flywheel?
I think I read somewhere that the engine must be removed to replace the flywheel. On my Corvette it can be done with the engine in place after transmission is removed but I do not know if same is true for Benz's . If the engine must come out, that will likely open Pandora's box and a host of problems. I say that becasue 10 years ago my Corvette paint needed to be freshened up a bit and one thing led to another culminating in a 10 year long restoration of the entire vehicle.
Kurt

Strife · #4 03-19-2006, 11:18 PM

My 0.02, definitely check this out soon. With any luck, it will be the starter mechanism and not (yet) the ring gear (you COULD have two bad ones, it happens). I let this go on a GM car (the starter) and eventually had to replace the starter AND the ring gear after a few teeth broke. This was very expensive to fix. I note that the price of the ring gear in the PP catalog is astronomical.

Are shims involved? I know that on certain US cars there are sometimes shims in this area.

t walgamuth · #5 03-20-2006, 09:03 AM

def check starter too.

but it sounds more like you have done that and that leaves the ring gear unfortunately.

yes i think you should be able to do it with the tranny out only.

tom w