Another bad starter? How can that be?
 

Its a long story. I don't even know where to begin. The car in question is a 78 240 D stick. I have had trouble with starters ever since I bought the car. A few months after I bought the car the starter went out so I replaced it. That starter worked for almost a year. Then it just stopped working. No warning, no funny noise. It just stops. Turn the key and nothing happens. So I remove the starter and get another under warranty. This starter only starts the car about six times then it also stops working. When I take the starter back to the parts store they say it tests fine. So I went ahead and replaced a few items, thinking that it can't be the starter. I replaced the battery, and the negative and positive leads. Still won't start. So I bought a remote starter switch. I figure that if I can get it to turn over with the remote switch than it must be the ignition switch that is bad. Still won't start. I finally take the car to the local Indy shop to have the cars electrical systems checked out. Guess what? There is nothing wrong with the car except the starter is bad. So I have the mechanic call the parts store and let them know that the starter is worthless. I decided that I want a different brand starter so I get my money back and go to Kragens. There I purchased a starter and installed it. That was on 6/23/01. Yesterday that starter died. The manager at Kragens would not give me another starter because he says that it tests fine. So they gave me my money back. Now I have a car without a starter and no clue what to do. By the way the car is very easy to bump start. I only have to get it going about three miles an hour and then dump the clutch in second and it starts right up. Help. I have no idea what to do. Any suggetions would be appreciated.

May be time for a new MB starter? Were the ones you purchased new or rebuilt?

Mad Mercedes,

Starters usually need to be rewound when they fail, and very few rebuild shops invest the cost of a rewind. If it is truly shot, and starting a Diesel is a huge strain on a starter, the insulation will have broken down from excessive heat. This gives the current a path to follow that does no work. And Nature likes to do that.

An electric motor for commercial use is designed to some pretty specific but flimsy standards. It will be rated at the maximum torque or power, depending on how the customer looks at it, for a given duty cycle, which is not emphasized most of the time. You have to be aware enough to look at that. Anyway, a starter duty cycle is pretty minimal for its life. Consequently they are not made to run in any duty cycle that approximates continuous operation. In your car and mine, they will see conditions that are max load long enough to try to reach a thermal equillibrium. Under those conditions the machine should be rated at about a quarter of the load. Heat losses in the starter stator winding are based on Ohm's law, and run at the current drawn to the second power (squared) so your starter, under serious cranking is seeing a temperature rise that can be harmful to the insulation. A rebuilt starter that checks out at room temperature for winding resistance to ground may not do well with heat as insulation resistance drops rapidly with temperature. This is why a lot of rebuild shops do not notice the stator is shot, or near shot. So, we Dieselers ruin starters faster than most others and when you buy a rebuild you need one done by a reputable source.

I have had very good luck with the starters for these cars offered by FastLane. I believe they are genuine Bosch rebuilds and they seem to last, and start a Diesel with no apparent strain. Be sure you order the heavy duty version, as all W123 240D and 300D are physically interchangeable, and I believe that holds for the W126 cars too. As time went on MB and Bosch built more capable starters for these cars, and the later models have what is known as a "heavy duty" starter. That is the one you want and I think it is listed for the 300D and 3000SD. I got mine via normal mail in a few days, and I have used their express mail service a few times where the item usually arrives earlier than expected.

Good luck, Jim

Also: What size battery are you using? Battery voltage after glowing but before engaging starter?

I guess I will give Fastlane a try. What have I got to lose? Dabenz I have the right size battery. My charging system works fine and the voltage was checked by my indy. I am pretty sure I have ruled out everything but the starter. THanks for the replies.

Update on the starter situation. I sent my wife to Kragens to get another starter with the money the manager gave me for the refund. $193.04 is what he gave me and what she paid for a 300
D starter. The box it came in says "Remanufactured. Not Rebuilt.". It is a Bosch. It claims that the field coil is tested. The brushes are inspected. The armature is remanufactured. Bearings replaced. Commutater is new. Drive assembly new. Bushings new or inspected and gauged. Solenoid assembly remanufactued with new contacts and tested for pull strength, and that all starters are load tested to meet or exceed original equipment specifications for voltage and amperage. I installed it and it works, just like I knew it would. Now for my next question. What is it about my car that is killing starters? I assume that heat is a contributing factor. The exhaust pipe runs right by the starter. Is there a heat shield that is missing? My cars temp gauge hardly ever even climbs to 80. When it gets close is when it is over 100 outside and I have the air on. It does reach 100 alot in the summer in my area. Jim Smith you seem to know alot about the subject. Do you think that if I wrapped the exhaust pipe with some kind of insulation, where it is closest to the starter, it would help. I can't think of anything else that would do it. The car starts right up. I don't have to do an inordinate amount of cranking. In fact I bet it starts up faster than most 240s. Thanks in advance for any advice.:confused:

MadMercedes,

Unless you have an exhaust leak that is blasting the side of your starter and cooking it, I doubt the underhood conditions of your car differ significantly from most other 240Ds. If this new to you starter is really one with a rewound stator, you should see some additional life, something approximating 7 to 15 years.

IF you get another failure in under a year, you will need some additional information to diagnose the issue. I would not suspect your car, but a typically remanufactured starter. While the starter may test ok at room temperature, it is not the same under the hood, or after you run it at full load for a minute or two. One of the rules of thumb is for every 10 degrees F the temperature rises, the insulation resistance is halved.

By the way, when you say the starter does not work, what exactly do you mean? It won't spin at all, or it spins slowly, or?? Does the unit make any noises? There can be issues with the pinion gear engaging the flywheel ring gear, and the solenoid travel. In some cases installation tolerances can affect these, but in most cases it is not sensitive to installation.

Well, I hope things are better with this starter. I know it sounds a little hokey that remanufactured starters could be defective but believe it. Happens with alternators too. Good luck, and I hope this helps, Jim

When the starter decides to stop working nothing happens. Get in the car let the plugs glow and turn the key. NOTHING. The starter does not make a noise at all. Like I said earlier I have tried a remote starter switch. That cuts out everything but the battery and starter. Still nothing. Then when I take the starter to the parts store it always spins in the stand. Just like there is nothing wong with it. :confused:

When NOTHING is heard when putting electricity to a starter , am I wrong to feel the problem is in the solinoid instead of the starter itself...?
seems like the solinoid plug should make some noise if it is working,,, whether or not the starter will turn after that... ... Greg

Bad Starter
 

Greetings,

My '82 240D had exacatly the same problem. I would get a year or or so out of a starter before it complelty stopped functioning without warning. What happened was that the rebuilt starter that I was given at the parts store was intended for at VW Rabbit diesel! The casing and all the external parts are exacatly the same. However, the internal components required for a rabbit diesel vs a Mercedes diesel are too weak to perform the task. I would bet that you're situation is exacatly the same. I was alerted to this fact by finally giving up and having "The Mercedes Shoppe" in Puyallup Washington deal with it. Ever since the shop installed the correct starter, I never had a problem again (with the starter that is) Hope this helps:)

That fits with the NO Sound symptoms , just as a key switch problem would... if the solinoid is getting electricity and working it should make SOME SOUND. At the parts shop it was getting electricity... something in the car is keeping it from getting electricity if there is no sound (but a functional unit)........ Greg

The odd thing here is that he has had a shop determine a starter that was installed was bad, and he has used a remote starter switch to check the system out and got a "no noise" response. The remote starter set up should bypass the transmission and key interlocks, shouldn't it?

It sounds to me, if the starter is "good," like the starter mounting flange or the bolts, through which a ground is usually made, are painted or not grounded somehow. Or he could be getting bad starters with internal grounding or power connection problems that only show up after the stator rotates a little in its frame. Edit: The stator is not supposed to rotate in its frame, as it is supposed to be keyed or have some other means to transfer the torque reaction to the mounting flange bolts. If this is not a suitable keyed fit, or there is a damaged part and a little movement is allowed, the integrity of the internal and external electrical connectors can be compromised. It is feasible that taking the starter out agitates it enough to allow the connection to be sound enough to withstand the starting/accelerating torque, so it works on a stand. Installed or loaded, the additional current demand and toque produced might simulate the conditions in the car better.

When my last starter replacement on the 240D was undertaken, the old starter had some internal structural failures that made it respond very much like is being reported here. NO sound. But I knew I had beaten the starter to death with the broken engine mount. When I took it out it was not a sound assembly. The connection end was loose, not falling off, but not tight. But it was electrically damaged as well, on the inside. Since I wanted the core value, I shipped it back "whole" so to speak, meaning not in pieces.

It also makes little sense, without some additonal data, that his key and/or starter interlock with the transmission would crap out and then be fixed by rummaging around with the starter. It seems like replacing the starter would have little to do with fixing a key problem or interlock problem, even temporarily.

I have another question, does the starter ever work intermittently, or when it dies is it dead for good, until you take it out and give it to the shop to check?

Well, this is another interesting mystery. Good luck, and keep us posted with the results. Jim

Jim, what you say is true also... how about my theory that NO sound indicates soliniod problem/solinoid not getting electricity ? That fits this set of symptoms also (?) Greg

Greg, I agree. It is just not clear where and why the power is not getting to the solenoid. Or why it works or appears to work in the shop on a stand. I am curious about what it is that is not working and displaying this set of symptoms. Jim

Could the shop test have bypassed the soliniod? just put power to the starter .... ? This is a real mystery if all the facts are correct....That it had happened with more than one starter is strange ........Greg

Well first of all to answer the question of whether or not it is in park. The car is a stick. Before I had bought the remote starter switch I could think of no other way to test the starter myself than to remove it from the car and use my 10 gauge jumper cables to excite the starter. Nothing happened. However upon replacing the starter into the car it did start the car a couple of times. So with that starter in was intermittent. Kind of anyway. I am going to have to look into this idea that I may be recieving the starters for a VW. Thanks again for all the ideas. This 240 is the family car and I hate the fact that I have to worry about my wife and kids getting stuck somewhere because it won't start.

I looked into the VW, Mercedes Switching thing. I looked at the starters from 74 all the way to 98. None of them even come close to being a match. Elliot the Mercedes Shoppe must of been pulling your leg. The starters in question would not even bolt up. Completly different beast. If you compare the starters on Fastlane you will see what I am talking about. Well the latest starter has started the 240 about 15 times since I put it in. I guess I can expcet to get about a year out of it. Thanks for all your advice and time.

MadMercedes,

Still contemplating the evidence, but if the starter you have is really a decent quality item it should last more like 7 to 15 years, depending on how you use or abuse it. Keep us posted, Jim

MadMercedes--"to answer the question of whether or not it is in park. The car is a stick. "

The factory shop manual claims that some manual shift 123's have a switch that is activated when the clutch pedal is put to the floor.... so for future reference when people are reading this thread I wanted to add that....it will give the same symptoms as a auto trans car with the neutral safety switch out...

If you do a search on starters on this board, you will find quite a few people describing similar symptoms to what you detail, but not as extreme. For many. the problem is intermittant. For instance, on my 85 300td, there is sometimes a hesitation, before the starter gives any indication of having current, when I turn the key to start. In cold weather it gets worse. I've never had these symptoms on another vehicle so it seems odd that is found repeatedly on MB diesels. Perhaps it is a result of diesel starters living a harder life, but I suspect there has to be another explanation. It sure seems to be an issue of current not getting to the starter, particularly in your case where they are testing ok off the engine.
In your case, I would probably try running a ground strap directly from the starter to a reliable ground and see if it made a difference.

Anyone else have an hypothesis that explains these widespread symptoms that seem unique to MB diesels?

Note that this thread is over a year and a half old. Apparently, leathermang has been contemplating this for a while. :o

Photographic Memory ?
 

Rick, how about the theory that I just ran across the info about the clutch switch .... and remembered him saying that he did not have a " park " switch due to having a stick... and thought I should complete that thread ? Could'ev happened like that ... didn't , but could'ev.... LOL
How about the things which could be said about someone that reads the posting dates of all the posts in a thread ? Too much time on your hands ? How is your boat floor ? Spring is almost here....

I like your theory.

As for the photographic memory, I'd say the lab is a little backed up on developing. ;)

240D with intermittant starting problem
 

Hi, I know this forum took place some time ago, but I was hoping that someone may now be able to better addredss a similar problem I am having with my 1978 240D that is having INTERMITTANT starting problems. It works fine much of the time, but sometimes won't turn over even though the glow plugs do their cycle. no click sound. If I wait &/or move the auto transmission back & forth it usually turns over after a few more tries. Sometimes this won't though .. until the next day. Most often, it won't start after I've driven it for a while. I cleaned the connections to the starter and the battery terminals. I also cheked at the transmission & found the plug from it (kill switch i think, only allowing it to start in park & neutral, a little shabby and I pressed it it better. Still have the problem. Possibilities: the ignition switch? transmission switch? or the solinoid or starter. It's cold where I live and I often have to use the starter longer than usual to get the engine going if I haven't remembered to plug the block heater in over night. Does anyone have any thoughts/suggestions? Thanks in advance.

When one of these starters won't even click, ENSURE THAT THE CAR IS IN NEUTRAL and then use your lug wrench to momentarily short between the big nut on the solenoid and the big nut on the starter just below it. This will jog the starter and it will most likely then start, if not, do it again. This is how you can get home.

Once a starter starts doing this, if the motor is in good shape without excessive end play, a new Bosch starter solenoid will make it good as new. On a 240D, you can replace the solenoid without removing the starter. Don't even think about trying that on a 300 though.

Good luck,

I see this thread is still alive. Last post only a few weeks ago. I replced my '82 240D starter last May (11 months ago) when the solenoid kept "sticking on" (intermittantly). Got a new (rebuilt) unit direct from MB. Put it in myself. Been fine for 11 months until today. Drove around then parked at a store. Came out and only heard the solenoid clicking. No starter noise at all. Tried moving back and forth between park and the other gears to no avail. Was sitting waiting for the tow truck when I decided to try it again (about 30 minutes after the first attempt). It fired right up. It's only in the 50s (F) here today so I can't say it was real hot but the thought of a temperature related problem crossed my mind before I tried it that last time. Came home and the connection at the starter was slightly loose (I was able to tighten it a little, anyway). Sprayed some contact cleaner on the lugs after loosening them up again. Tried it several times while it was up on ramps and naturally everything seems fine. I'm just hoping that this is not the start of an annual affair each spring. It does have to crank for some really long times in the winter. Like 6 or 7 long cranking sessions. Well, that was before I replaced my 23 month old Interstate battery. I liked the idea of putting a separate ground strap from the starter to ground. Are there any other suggestions on what to try to "guarantee" (ha ha) that this won't happen again?

- Jeff