83 300D: recurring starter sticking problem
 

I bought the car in sept 2001, shortly after the starter stuck on after starting at a rest stop and burned up before I was able to disconnect a battery wire. I was able to call a tow truck to pull me down the highway and restart the car to get back home (1200 miles, never turned it off again).

Once home I had the starter replaced with a quality reman. The problem never occured again until today. I was leaving to get new tires installed when the same problem occured. I was able to grab a 13mm wrench and remove the battery cable before any damage occured (ran for less than 30 seconds)

Now keep in mind this is over 60,000 miles later, without any starter problems, and the same thing occurs again. Is the solonoid built into the starter? is there possibly somthing wrong with my ignition? I am sure the problem is either a live short into the solonoid from the key, or a dead solonoid that somehow got stuck in the on position. has this happened to anybody else, and what should I check first? Hooking the battery back up and the starter still comes back on, although it does not catch the flywheel (just freewheels)

Well
 

That was a subtle hint. :D LOL

I havent found anything similar to my problem... and yes, I searched before I posted. I find tons of starters not engaging, cold starting problems, etc. I dont find anyone with a starter that will run until the thing blows up.

am I missing somthing here?

I am nothing if not subtle.... LOL
Sounds like a dirty solinoid sticking in the on position to me...
Did putting a new starter on it fix it 60,000 miles ago ? If yes then it was somewhere in the starter/solinoid...

Does it happen after heavy or prolonged starting? Battery low perhaps?

I've run across that problem on older fords and chevys with a low battery on occasion. Not sure if the Mercedes solenoids would behave the same.

A real two pipe head scratcher here.
 

I am confused, is it engaged and turning the engine or just setting there, not turning the engine and running?

#1. Solenoid contactor plate self welded to contacts.
#2. Possible key start switch fault, mechanical damage is most likely here.
#3. Possible dirty centrifugal clutch = locked engaged with fly wheel.
#4. Possible broken solenoid contactor plate, return spring.

:( To bad you are not local; I would like to do forensic diagnosis on it. :(

:) I hope that you took no offence from leathermang or myself, none was meant. :)

FYI, if you do a search with no results, please mention it in your post. :)
Many senior and founding members do get tired of answering repeat questions, when a simple search could find the answer. :(
:eek: Some of us are as subtle as a sledge hammer, especially on a rough day. :eek:

The starter motor turns, but does not engage the flywheel. The ignition key switch seems to be functioning fine. I even tried putting the car in gear hoping to activate an interlock, no luck.

I was lucky enough to be 3 feet from a 13mm wrench and saved the starter from burning up. I just got home from work, tried it and same thing still occurs. I will try hammering on the solonoid later. if this doesnt fix it, screw high $$ starters, I am going with the $99 advance auto lifetime warranty unit. This did seem to disappear after the replacement of the old starter, but it strikes me as extremely odd that it crept back up on the new starter over two years later. I was hoping it had happened to someone else, but I guess not.

I have also been a member for a over two years, and a lurker much longer. I am fully aware of the search feature and the only reason I am not yet a senior member is due to the fact that the search works so dang well I never have to post.

Some topics have lots of good threads already extant... some topics are best found under words not usually used by people...and you did not say that you had searched or tell us the words you used for searching.... and the search has admittedly been suspect lately........ I just did the search and posted the url...
The solinoid is what should take the sliding gear on the starter shaft forward enough to engage the flywheel ring gear.... and some design solinoids would require full movement of the electro magnetic slug in order for the starter to rotate ( because the copper contact point is on the end of the slug )... so all this points to either a messed up engagement mechanism... like broken gear, or malfunctioning solinoid.
Why don't you take the starter/solinoid off the car and to the local parts chain nearest you... they will usually test them free while you watch....

Car54,

Its definitely not your ignition system. Psst: You don't have one.

P E H

And the answer is!!!
 

Solenoid contactor plate self welded to contacts. :(

Replace the starter Solenoid and your trouble will be gone. :)

Have a great day. :)

strange
 

so it would be pure coincidence that this same thing would happen to car54 on 2 different starters? also no one else here has had this problem?

:confused:

Attention: car54 please save the old solenoid
 

Attempting to theorize without data is futile.

I stand by my diagnosis. :)

I would like to do forensic diagnosis of the solenoid, with pictures. :)

Here is a simple theory to explain the facts. :)
Both starters came from a local (only to car54) rebuilder who does very low volume of MB product, the rebuilder got a box of vintage rebuild supplies for free or little money, the parts are not stored correctly, and have developed serious corrosion issues, when used in this condition, the run away starter occurs. :(

Sadly, I have seen this exact case in seven states on Ford, Chevy, BMW, VW, Chrysler, Packard, AMC, MG and Fiat. :(

Note:
"Matt", states: Now keep in mind this is over 60,000 miles later.
That is very good life for a cheap rebuilt starter

actually the first starter came with the car, that I purchased from Turbodiesel on this board. I dont know its age, it could have been 8 or 18 years old. The replacement came from Olympic foreign auto parts, and appears to be a bosch reman.

Hello Matt
 

Here are some graphic answers. :)