Is my starter beginning the death process?? - PeachParts Mercedes-Benz Forum

ayalar007 · #1 10-27-2004, 11:00 AM

Hi to everyone!
I have a question that is worrying me. When I first got my 300SD (W126) from dad, I had an intermittent problem with the starter. The problem that on startup in the mornings the starter would ocassionaly spin freely, but not engage. I really paid very little attention to it, all I would do was re-try the start-up process. Well 7 months into owning the best car I have ever had,

it is now doing it every morning. The problem is only in the morning, or when cold. It never does it when warmed up to normal oper temp. It has never left me stranded anywhere, the fix is usually to turn the key back to the off position and try starting it again.....and it does.

My worry is that one day, when I try the second startup process....it wont!

What do you guys think???

oilslick · #2 10-27-2004, 11:11 AM

It sounds like you are getting close to a rebuild on your starter or a replacement IMHO. Get a used one if price is an issue. Not a tough DIY job.

Mine was doing the same thing and one day...........................my wife was coming to pick me up and the car was left in a parking lot all alone.

I don't own that MB anymore.

Hope you get it fixed and working smoothly!

Kevin

autozen · #3 10-27-2004, 11:19 AM

Yep. Sounds like starter time. If you are going to keep the car, buy a quality rebuilt starter and not a used one. Remember you already have one used sterter, and you know how well that works. I can't stress enough to bite the bullet and buy a Bosch rebuilt or similar. Do not waste your time on a cheapie from Kragens or Shmuucks or any other chain parts store. The rebuilt stuff is garbage.

Good luck,
Peter

boneheaddoctor · #4 10-27-2004, 11:25 AM

Yes, your bedix or solenoid is going south.

Replace it before it leaves you stranded. One day soon it will.

ayalar007 · #5 10-27-2004, 11:39 AM

Guys,
thanks for all of your inputs on this. I was hoping all it needed was some sort of cleaning or something like that.....I kinow I know that's just me being Naïveté. These cars are so awsome that most of the time you really only have to do little "tune-ups" to things and they just keep going like that darn pesky energizer rabbit!! But I guess its a no go on this one. Its kinda hard for me cause I'm a student right now and I dont really have all that much money, and I hate getting a used piece of crap that i'll have to replace again!

P.E.Haiges · #6 10-27-2004, 11:39 AM

ayalar007,

I have the same problem with my '79 300SD. It did it yesterday for the first time since last winter. I can plug the heater in and get the engine started all winter, at least I could up until now, so I'm not going to fix it unless I have to. As soon as the engine and starter get warm, the problem goes away.

Actually its not the starter, its the solonoid. For some reason when its cold it doesn't hold the pinion gear on the starter shaft into the ring gear. So the fix is to just replace the solonoid which is much less than replacing the entire starter.

The solonoid has a pick and hold coil. The pick coil pushes the pinion gear into the ring gear and then it is deenergized and the hold coil is supposed to hold the pinion there. So its possible that the hold coil is weak and the cold exacerbates the problem

Its up to you if you want to repair yours. But it shouldn't cost you as much as you might have thought. If you have the started out, which I think you have to do to replace the solonoid, you might check the starter over and replace the brushes if required and clean and lubricate the starter.

P E H

Jim Anderson · #7 10-27-2004, 11:44 AM

It wasn't as scary for me cause I have a backup starting system, a standard transmission. It's your bendix, that's the ratchet thing on the gear, and it will get worse. As mine was going I started looking for auto electric shops and asking if they could and would just replace the bendix. I found one that would before it completely died and it ended up costing me $30.

Edit: I just re-read it, it could also be a dirty solonoid. I've been able to take them apart, clean them up and lube them.

KCM · #8 10-27-2004, 12:15 PM

I think the problem may be simple, the starter drive is gummed up. The ratchet mechanism is simply not engaged because oil and dirt have gummed it up after many years. As the car warms up, this sludge thins out and it starts working. I have a 300D that did the same thing as you described, and a 200D which is doing it now. I took the starter off and the starter drive out and immersed it in diesel, working it to clean and wash the gunk out. Has worked fine ever since. You may be able to clean it good without dissassembling the starter using WD-40 or another cleaner.

dieseldiehard · #9 10-27-2004, 12:40 PM

I have cleaned them both ways, disassembling the solenoid from the starter vs. leaving it in place. The latter method is better, trust me. I had the unfortunate experience of having to pull the starter a second time because I didn't reassemble it properly.
IMHO the crud in the solenoid is mostly carbon dust from the brushes. WD-40 is a good cleaner, as would diesel. Compressed air is necessary to to blow it out, its a big mess so do this outdoors unless your garage floor is already crudded up.

ayalar007 · #10 10-27-2004, 02:31 PM

Guys, Thankyou very much for all your feedbacks! I really really appreciate this. I kinda thought that a little cleaning might be called for, but to be quite honest I really didn't know what I was looking for.

Bottom line seems to be that I have to bring the starter down, regardless. I guess its a small price to pay for driving one of the best cars around. I will certainley look into doing this ASAP. I have to wait until I have time off from school since the old girl will be out of commision while I do this, and I need her to get to school. How should I go about cleanign this, just submerging the whole starter in diesel fuel, or is there a specific part that only needs to go it, while another part SHOULD NOT???

Again thanks to all

Ken300D · #11 10-27-2004, 02:53 PM

Very typical failure mode.

You may be able to solve the problem through cleaning. Attempting to do that can save a lot of money. But you do have to go off and on with the starter at least once - and again if it doesn't work.

If you have the bucks, a good solution is the Bosch rebuilds that are sold here on FastLane. They are a good value.

I bought a used starter on EBay and it was great for two weeks, then started doing the same thing. So I went with the rebuild and its been no problem.

It is a do-able job with the right tools, but still not enough fun that I want to do it several times in a row while testing my cleaning and refurbishment capabilities.

Ken300D

ayalar007 · #12 10-27-2004, 03:04 PM

Quote:

Originally Posted by Ken300D

Very typical failure mode.

You may be able to solve the problem through cleaning. Attempting to do that can save a lot of money. But you do have to go off and on with the starter at least once - and again if it doesn't work.

If you have the bucks, a good solution is the Bosch rebuilds that are sold here on FastLane. They are a good value.

I bought a used starter on EBay and it was great for two weeks, then started doing the same thing. So I went with the rebuild and its been no problem.

It is a do-able job with the right tools, but still not enough fun that I want to do it several times in a row while testing my cleaning and refurbishment capabilities.

Ken300D

...I hear you!!! I have been thinking the same thing. The only thing that throws me off is the fact that it NEVER does it when it is warm. When at normal operating temp, it turns the engine perfectly without a hitch. Do you still think its ready to go??? I would venture to think that if it was ready to go, the intermitance of the problem would happen at any temp? Is that a safe assumption???

Ken300D · #13 10-27-2004, 03:08 PM

Yep, the cold temperature issue is also typical of this problem. It will get worse and worse. I think I probably went six months until I couldn't stand it any more.

At first it would only free-spin once. Then it got to the point where it might take five attempts. etc. etc.

Ken300D

GregS · #14 10-27-2004, 04:05 PM

Does anyone know what you should lubricate a starter with? I have some synthetic Mobile 1 bearing grease at home - would that be o.k.?

GregS

Jetmugg · #15 10-27-2004, 04:14 PM

The most cost effective solution is to repair/have repaired your existing starter. Most towns still have a shop that specializes in starters/alternators/electric motors. Find that shop, take them your starter, and they will probably fix it very quickly and cheaply. These starters aren't too complicated, but some experience working on them sure helps.

The toughest part of the job will probably be removing the starter. Tight bolts/hard to get to.

SteveM.