My 1987 300TDT wagon suddenly won't start. When I turn the ignition to the second position the glow plug light goes on and it buzzes like normal, but when I turn the ignition to the third position to start the engine, nothing happens.

I thought the ignition tumbler had worn out, so I replaced it, but the same problem is happening.

Any suggestions? thanks

The Tumbler is part of the Lock and is the part you need to put your key in and turn.
The Ignition Switch is the part that the wires go to.
which one did you replace?
Site wit manual
http://www.ps2cho.net/downloads/MB%20CD/W124/Main.html

Most transmissions have a switch called the Neutral Safety Switch that keeps your car from starting unless your shift lever is in are in Park or Neutral (or at least the cars with Automatic Transmissions do).

Try starting your car with the lever in netual instead of park.

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84 300D, 82 Volvo 244Gl Diesel

What do you mean by "buzzes like normal?" Buzzes because you haven't fastened your seatbelt yet or something else?

Make sure the transmission is in Neutral or Park. Wiggle the selector, try moving it back and forth through the gears as you try the starter. The neutral safety switch is a common failure point.

Is your battery fully charged? Check the battery voltage. Terminals clean and tight? Engine to chassis cable clean and tight? Try turning on the headlights--nice and bright?

If all those are good, you could have a starter motor failure.

Jeremy

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

Does anyone know if there is a Terminal Block like there is on 123s that he could jump to see if his Starter Motor will crank?

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84 300D, 82 Volvo 244Gl Diesel

The similar/identical terminal block is buried between the battery and the middle firewall, PITA to access w/o pulling the battery. However, there is a terminal on the driver's side that can be connected to +12 to trip the starter motor. It takes a special factory cable that few of us have. You can also make your own cable but I'm willing to bet that such a project is not within the OP's ability (apologies if I have read the situation wrong).

Edit: Pictures added of terminal block and factory remote start cable

Attached Thumbnails

   

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

I replaced the ignition tumbler, which the key goes into. tx

By "buzzes" I mean that it makes a tone noise when the glow plug light is engaged, the way it is supposed to. thanks

Success!!! Thanks so much. Turns out the gear shifter somehow was in reverse instead of park. But I'm glad I changed the ignition tumbler anyway, because the key was occassionally getting stuck and not turning properly.

Glad you got it handled, but uh........

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

Still do not understand. There is no noise made during pre-glow unless you don't have your seat belt on, have the driver's door open, or some other fault.

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

The noise during pre-glow is because I don't put my seat belt on until after I start the car. tx

Ahhh . . . "buzzes like normal" . . . normal for you. Sorry, I didn't understand. Thank you for following up with the explanation.

Jeremy

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

If there's any fore-aft slop in the shift lever, it might be time for new shift rod bushings. There's one at each end of the rod that connects the bottom end of the shift lever to the transmission.

http://www.peachparts.com/Wikka/W124ShiftBushings

Sixto
87 300D