Hello all. After seven months of faithful service, my 85 300D refused to start last monday. The starter refused to turn over. It was lunch on Monday and it had started just fine when I set out for school about four hours earlier. Nothing of the kind had ever happened before. It would click once then refused to click again unless allowed to sit for about ten minutes, then it would click again then nothing. The windows, radio and lights all worked fine. I hadn't left anything on. I took all of the battery cables off and cleaned them. I cleaned where the negative terminal grounds to the body and where the positive terminal. I got a jump from two different cars with two different sets of cables. One was an early 90s model Mitsubishi Eclipse with pretty old cables and the other was my bimmer, which i replaced the alternator on only about a year ago. When trying it with the bimmer I used my less-than-five times-used cables and still the same thing, one click then nothing. So its Sunday now, six nights my car has spent in the unlocked school parking lot , and unless I can get it started I'm facing another night and I really don't want to test my luck anymore. So I get up early, finally resigned to pull the starter and have it tested. My dad still insists its a bad contact somewhere and comes with me, bringing his 85 Ford F150. He gives my cleaning job the once-over and is satisfied that all the contacts are clean. He whacks on the starter, no difference. Then he pulls the battery out of his truck and puts it in my Mercedes. STILL no difference. Finally, as I'm crawling under the car to tackle the starter, he says we should try jumping it with his truck. We attach our cars and he revs his truck for about five minutes. (Yes, I did rev the other two cars when I had them hooked up and did it for about five minutes.) So I get in my car and, big suprise, it does the same thing. I'm really depressed by this time but I decide to try it one more time. It started!!! I drove it the twenty minutes home, killed it and started it about three times and its started just like a dream. It died on me Monday the 16th and I fixed it this past Sunday. Its still running great but I feel like this problem is still lurking, waiting to rear. Oh yeah, and I did short the violet wire at the glow plug relay, thinking it might be the neutral safety switch. Still just one click and nothing. Sorry for the extensive post but I really don't want to get stranded and I wanted you guys to know exactly what I'd tried and hadn't tried. Any help would be greatly appreciated. Thanks in advance.

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Seth

1984 300D 225K
1985 300D Donor body
1985 300D Turbo 165K. Totaled. Donor Engine. It runs!!!
1980 300SD 311K My New Baby.
1979 BMW 633csi 62K+++? Dead odo

Don't know why diesels do this. I think it is a solenoid issue. We used to have a similar problem on a diesel farm tractor and I had to cycle the key a dozen times one time before my 300 SD would start. I imagine someone on this board has cured this problem. I have driven the car over six months since this incident with no problem. Could be a problem with the contact in the transmission also. If you have problems again try putting it in neutral and see if it starts!

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My Daily : 96 E-300 Diesel with 195,000 miles
Retired: 92 300D 2.5 T 345K miles and for sale
Retired: 95 E320 157K miles and currently parked with blown engine

Both retired cars are for sale as is my w124 shop inventory

I will suspect a 'dead' spot on the commutator. When the starter stops with the brushes on that spot they can not conduct current, and the starter cannot turn.

In this case, no amount of battery power, even with jumpers, can force the current to go if there is no contact.

Given time, the brush pressure might slowly make contact (whacking the starter might move it a bit...) so it now conducts and the starter works. When it stops, it might be at some other random orientation.

When the starter again stop with the brush(es) aligned on the 'dead' spot the problem will return.

It might be time to schedule removal of the starter and have a look, rebuild or replace.

Best Regards,
Jim

Sailor,

If the solonoid clicked, its probably not a dead spot on the starter. The current has to flow thru the starter to energise the pick coil which pushes the pinion gear into the ring gear and closes the contact points.

If the contact points in the solonoid are worn, dirty or corroded they can work intermittantly similar to your case. Check the contact points and clean or replace them as needed. You might not have to remove the starter to do this, just the solonoid.

P E H

I had a similar problem.

I would guess it is the Neutral Safety Switch (NSS), on the driver side of the transmission box (under the car).

U should be able to start ur car with the gear shift in the 'P' or 'N' position.

U may want to try this the next time u have trouble starting the car. In the engine compartment, on the passenger side fender is a small black box, about 1" x 3". Lift the cover and u will see 3 terminals. Jump the 2 furthest terminals, in that box, from the car battery. This bypassess the NSS. If it starts, then ur problem is the NSS.

Tell us what u find out.

This is exactly the same symptoms of something that bit me. Check the grounds battery-chassis-engine. Especially the chassis to engine strap. My problem turned up as a loose bracket that the engine ground strap was attached to. One time starting, everything would be perfect, the next nothing. Two starters later.

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Sam

84 300SD 350K+ miles ( Blue Belle )

i dont think it will click if the neutral switch is the culprit. i am thinking solinoid.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

If you really need to get it started to get it out of there, have someone tow it to about 15mph, drop it into "S" or (2) on the gear selector, turn the key to glow/run and it should fire/get going, it details this in the manual....these cars can be tow started in the lowest selector setting even with the auto trans......

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

maybe it's a german thing..
mine does this too and has been doing it off and on for years. cycling the key has never failed to start the engine in the end. it happens more often when the engine is hot, but has happened once or twice from cold.
i remember that my 73 super bug used to do this as well however that engine was easy to push start with a manual 4spd.
oh and i even had it happen to a cessna airplane that i was about to get a ride in i said to the pilot, no problem just cycle the key and she'll start!
and so it did...

another member here solved this same problem in his TD by replacing the starter.

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1984 300D Turbo - 231k....totalled 11/30/07 RIP

I'm at my wits (sp?) end. Yet again, I've cleaned all the contacts, had the battery and alternator and now the starter tested and all came out as perfectly fine. I've tried grounding the engine out at the turbocharger and it still made no difference. Is the culprit the solaniod? Is it possible to take the solaniod off without removing the starter? After having the starter tested in the car at Orielly's, it's started ok for about the past ten starts but it died again on me tonight. Jumped it to a very nice passerby and it started right up. This is a very recent problem. It just sprang up about a month ago, I want to say after the first warm weekend but I'm not sure. Cycling the key doesn't make a difference. Any advice will be greatly appreciated. I'm willing to try anything at this point. Thanks in advance.

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Seth

1984 300D 225K
1985 300D Donor body
1985 300D Turbo 165K. Totaled. Donor Engine. It runs!!!
1980 300SD 311K My New Baby.
1979 BMW 633csi 62K+++? Dead odo

Its got to be the solenoid, I would rule out the nss, it wouldn't even click if that was the problem, the solenoid is a non lubricated part that is still exposed to considerable heat from the engine, after so many starting cycles theres grime in there, that combined with the fact that the solenoid exerts a very strong force can cause it to get stuck sideways ever so slightly and with the tight clearances you have in there is enough to prevent it from moving un til something knocks it loose. I would pull it and remove any grime and use very fine sand paper, put a little oil on iit and try it out.

i dont think it is practical to remove solinoid wo rem the start. it also could be bad ground. the neg strap on batt bolts to bod and should be removed and cleaned. there is also a ground from engine to bod and this one is often left off when a motor is removed and reinstalled by accident.

sometimes on older cars a neg ground needs installing from starter bolt to battery neg bolt down to counteract degradation of other ground contacts from corrosion. it is a very frustrating thing tha c omes on gradually and is hard to figure out.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

This is really puzzling, since a jump start adds battery capacity, but otherwise does nothing to the the solenoid or starter. Are you sure of the battery and charging system? Does the battery have enough power to light the headlights brightly when the starter does not engage?

I am beginning to wonder if the contact in the key switch is bad... The next time this happens, can you put a lamp/meter across the positive wire of the solenoid and ground to see if it is getting power from the key?

Best Regards.
Ko,

If it were my car I would just replace the starter. You may eventually figure out what and why it is acting the way it is, but in the mean time your patience will likely grow thin. I had a starter die on my car a couple of years ago, and I replaced it with a rebuilt Bosch, and it was defective....it occasionally would not turnover when hot. I think it had a bad motor winding that developed a fault when it got warm. Yours may have a fault only when cold? Who knows? The best thing you can do for a starter that won't work is replace it. Of course, a rebuilt starter is no guarantee your problem is solved.

Good luck!

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1976 240D
1987 560SL
2007 E320 Bluetec
1998 C280 (now son’s car)
1982 240D Manual - Sold

Question: Have you recently washed the engine...?

I have experienced electrical problems after washing my engine and getting cleaner/water into electrical components.

- Patrick

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1982 240D. 198k, Marine Blue/Blue, 4 Speed, Crank Windows, No Sunroof, No Rust, No Oil Leaks
2001 TDI. 197k, Lagoon Blue/Black, 5 speed, Chip, G60/VR6