1987 300D T won't start - PeachParts Mercedes-Benz Forum

darkman · #1 11-16-2004, 04:17 AM

i've used the search but i'm new at this and don't know what to check first. my car was running fine. the only changes i made were to:
1. add about 7 oz of Power Service Diesel Kleen to about 15 gals of fuel;
2. change a blown fuse (#7... backup lights, heater, etc.)
3. add 1 pt. Synthetic ATF because the ATF was low

then... (about 2 hours later)...
i drove the car for about 15 miles and could feel a noticeable difference in shifting and acceleration. after about 20 minutes, the antilock light came on so i tested the brakes to make sure they were working-- which they were.
after turning the car off, i tried to restart it and got nothing. No starter grinding-- nothing. The SRS light, lights, heater, and all the battery stuff worked, but from the outside you could not even tell that i had turned the key.
any ideas on how one of these things could have triggered this or does it seem to be something else that is unrelated??

darkman
1987 300D Turbo 191,100

dieseldiehard · #2 11-16-2004, 12:27 PM

Check the fuses again, if all OK, I would then look at the neutral sensing switch on the transmission, something has to be preventing the key switch from applying power to the starter. Unless the key switch suddenly failed (not unheard of on hi milers) And you can jumper the starter manually to pull in the solenoid (but I haven't tried to do this on the '87 300D yet)

#3 11-16-2004, 12:36 PM

Do a "Search" using the words won't start or starting problems in the diesel discussion area.

dieseldiehard · #4 11-16-2004, 12:50 PM

I haven't seen this topic as relating to the W124 very much on the Forum, its possible there is a difference between the interlocks in the '87 and the other (123, 126) diesels.
I learned how to troubleshoot this malady on my 300TD (123) in West Texas, at a gas station where it was just above freezing, a light northerly wind and it was Christmas eve, no tow trucks in the little town, and my insurance company had dispatched a tow from 80 miles away. During the time they were enroute I poked around on the transmission neutral lockout switch and it started. Gave them a call and cancelled the tow. I ran the engine all the way to my destination, adding oil to a running engine with lots of blowby was another experience I had on that trip.
Say, if you decide to sell that '87 I have at least three friends that want one. I just drove mine from SFO to LA and back, fuel mileage was approx. 26 MPG running 70 -80 most of the way. I briefly ran it up to 90 and 100 MPH where it was stable and still had some headroom. What a great car!
DDH
1971 220 (gas) 4-spd manual 106441
1979 300TD w/ ’85 turbo engine 295530
1983 300D 243280
1985 300TD 217300
1987 300D 259000

toknow · #5 11-16-2004, 02:22 PM

Which area in pittsburgh you are? I am from Pittsburgh!
It happened to me at the same day as you are, Sunday evening. The car stopped in the middle of the road. But it was very close to my campus, I pushed te car to the side with the help of my wife.
I called a friend to come and help. I was thinking that the car out of fuel! and the gauge showed very little. So, I got 2 gallons, and I put half of a bottle of red-line additive before the fuel. I staretd the car but it did not start. I tried again and again. I found in the fillter air bubbles. I kept cranking alot until finally it started.
Here is my theory:
The weather was getting very cold at that day, the fuel in the car was old, not treated for winter. So, the fuel "gilled" in the tank and allowed air to go through the system. The additive and new fuel cleared this. Also, I was not running the heating in the car, the fuel can be heated only if the acc is on.

So, try again,
good luck

jfikentscher · #6 11-16-2004, 02:25 PM

If the anti lock light comes on and the tach stays off it might be the over voltage protection relay behind the battery.

Joe

darkman · #7 11-16-2004, 11:52 PM

Thanks for all the leads. tomorrow when it is light i'll try the neutral lockout switch. truthfully. i picked up Chiltons because i had never heard of it before. i am very new at this but am a quick learner. (BTW toknow, i live out in Whitehall)
I just got this car 2 months ago after having searched for a good one for a couple of years.
The body is as perfect as you could expect of a car this age. absolutely no rust... 1 owner... interior like a 5 year old...upkeep & maintenance done at the dealership...etc.
An additional bonus was that the owner put about $2500 into it in the 2 years prior to letting it go (engine oil cooler sealed w/line replacement, brakes/linings replaced, A/C work

plus got an extra set of tires (snow!). Needless to say. i fell in love with it as soon as i saw/drove it so i won't be considering selling it soon.
I need to get some work done on the heating system. the other work is optional stuff that can wait. But first i have to get it started again.

I'll post the outcome tomorrow.

psfred · #8 11-17-2004, 12:08 AM

Try starting in neutral rather than park -- when the tranny linkage bushings fall out, the lever will not always go far enough to engage the switch. You will get a clicking from the tranny as car rolls if this happens since the locking pawl will not engage, just slip from notch to notch.

If it starts in neutral, crawl under and see if the tranny linkage bushing are still there on each end of the rod. Probably not -- remove lever from tranny with rod still attached, replace that one and re-install the rod, then the one on the shift lever as it's impossible to get the bushing in with the tranny lever on the tranny, and it takes three hands to install the clip on the rod with it in place as well.

Starter is on the LEFT (driver's) side on this car, below the windshield washer tank. YOu will need to pull the tank to check the wire (there are only two). See if you get voltage on the small wire when turning the key to start position. If you do, the solenoid is bad, especially if it does not click when you turn the key. If you don't get voltage, check the neutral safety switch -- no voltage there means the keyswitch is bad or you have a broken wire between the battery and the switch.

If the starter goes "clunk" and the headlights dim, but the engine does not move, the starter is bad, replace it. Mine locked up at about the same milage.

Peter

#9 11-17-2004, 06:27 AM

Quote:

Originally Posted by psfred

See if you get voltage on the small wire when turning the key to start position. If you do, the solenoid is bad, especially if it does not click when you turn the key. If you don't get voltage, check the neutral safety switch -- no voltage there means the keyswitch is bad or you have a broken wire between the battery and the switch.Peter

I've had two ignition switches in two different benzs fail in similar situations, the first time, (190E) I got it towed home and installed a on/off toggle switch for spark and a momentary push-button switch for starter. The second time, (87 300D) the end stop of the ign switch that springs the key back out of the start position when you let go the key, this spring broke and it no longer engaged the starter when I turned the key all the way, but the accessories action of the switch still worked, and the wheel lock had never worked! Hope this will be of some help to further diagnose your fault.

darkman · #10 11-18-2004, 01:39 AM

Not wanting to overlook the obvious-- & since i had been trying to start with no success-- i called AAA to check the battery and hoped to have him check the wires for voltage as per suggestions.
He said that the battery was too low to start the car and the alternator was even worse. He attached jumper cables and after about 5 minutes the car started right up.
The device he was using also indicated that the alternator was back up to its proper level. He told me to run the car for 45 min to recharge.
I idled the car for 15 minutes then drove it for about 10 minutes. Then I let it idle in the driveway for another half hour. When i went out to shut it off, the ABS light was on again and also the light next to it that looks like this

(i don't have an owners manual yet so i don't know what that is). I turned on the headlights and they were barely lit.
The people at MB roadside assistance said that 'as a car loses power the computer is designed to shut down non-essential systems in an attempt to conserve, so that may be why the ABS light came on'.
Should i just focus now on the alternator?

darkman
1987 300D Turbo 191,100

Rick Miley · #11 11-18-2004, 10:13 AM

These cars to all kinds of funky things when there is a low voltage condition. ABS and brake warning lights, tach and speedo failure, all that. Yes, focus on the alternator. It may be that you only need to replace the regulator because of worn brushes. It attaches to the back of the alternator with two screws, and costs about $15. Remove it and check the condition of the two brushes before you start shopping for an alternator.

psfred · #12 11-19-2004, 12:53 AM

Have the battery checked, too -- a bad battery will suck up all the juice the alternator can put out at idle.

Note that you CANNOT charge a dead battery by idling a car with an alternator, it simply will not generate enough current. A generator will, but not an alternator. If you've noticed, the headlights are just a bit dimmer at idle, and sometimes the blower will slow down some too -- this is a result of lack of voltage from the alternator. You must speed the engine up to 1500 rpm to charge the battery back up.

Peter

jfikentscher · #13 11-19-2004, 09:14 AM

Whwn the ABS light comes on and the tach is out at the same time, it is probably the overvoltage protection relay. Wiggle it and see if the ABS light goes out. Also the car might idle roughly when the ABS light is on. Easy fix. Just replace the relay. About $60.00.

Joe

darkman · #14 11-24-2004, 09:09 AM

First i want to thank everyone for helping me with this because you ALL helped me save about $250 on an unnecessary alternator.
I took the battery to WalMart and they had to recharge it for about 40 minutes before they could check to see if it was defective. The battery seemed to be okay.
I took it to WalMart instead of calling AAA again because I noticed that the car's clock had stopped 3 hours after AAA last charged it. So not only was i unable to charge it with the alternator (because i was trying to do so in idle-- a fact i learned right here), but the battery must be losing power even when the car is off.
One of the strange things i remembered was that in addition to the ABS and other warning lights coming on, i also heard a very low hum coming from one of the rear speakers. The radio hasn't worked since i got the car but i was told that all i needed was the activation code. I got that from the dealer but was unable to enter it when i tried so the dealer told me to bring it in so they could check it.
When i replaced the battery the car worked fine and has continued to work since yesterday.
My conclusion is that i must have done something trying to program the radio-- which was the day before the car failed to start-- that caused the radio to use power even when the car was off. I guess removal of the battery triggered the security mechanism that shuts the system down because i haven't heard a peep from the speaker and the battery is holding power.
Now i can use the $250 to start trying to find out what's wrong with my electrical system

Thanks again fellas!

k. darkman
1987 300D Turbo 191,100