I just started my car --'87 300D and as I began to accelerate I heard a loud bump under the car. It sounded like it was below the right backseat. I lost all acceleration and couldn't get any forward gear to engage.

I then (after braking) tried reverse. Nothing. Tried to put it in park to get out and look. It made a bad grinding sound that made me put it in neutral instead.

I shut it off and restarted. When I tried to shift from neutral to drive, I could hear something that sounded like it was spinning and trying to "catch" something-- but couldn't.

I pushed it to the curb and came here... the worlds premiere source of Benz Diesel assistance!

Seriously... I check this formum before I even start talking to a mechanic.

Thanks

__________________
k. darkman
1987 300D Turbo 200k

Take a look at your drive shaft.

__________________
1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

Thanks for the quick reply.
I looked under the car and I dont see anything external that looks different.

__________________
k. darkman
1987 300D Turbo 200k

Is your driveshaft attached at both ends?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I have to go to the car to check...
It's a few blocks away.
I'll see.
Thanks

__________________
k. darkman
1987 300D Turbo 200k

Loud bump, no gears, back seat? I would wager a pile of cash that it was your rear flex disk.

__________________
"spreading a trail of obnoxious where ever we go"
1981 300sd w/ 341,500 miles

http://www.wecrash.com/pics/ddda_banner.gif

Same thought here, I bet you blew a flex disc, be thankful it was during acceleration and not at 75mph or something. Damage is probably minor, hopefully.

__________________
-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)

I checked the driveshaft and didn't see anything. I turned the car on and moved through the gears. The noise sounded like it was coming from inside the trunk. I looked in the E-Class Bible, and saw the driveshaft flex disk. Is that it? What kind of fix is it and how can I diagnose it further to make sure? Coincidentally, I was three blocks from getting on the expressway!

Again, thanks.

__________________
k. darkman
1987 300D Turbo 200k

I hope you meant you didn't see anything wrong...

To be safe, check everything in the drivetrain. Transmission shifter bushings/links, flex discs, center bearing, etc.

__________________
http://farm8.staticflickr.com/7271/7...144c3fc1dc.jpg

You should have someone put it in gear while you look at the driveshaft to see if it is turning. Not turning, problem from front of driveshaft forward. turning-problem from back of driveshaft back.
Obviously, don't lie in front of the wheels while doing this in case the situation changes suddenly.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I believe you can check the flex disc visually for cracks and rips. Flash light and keep the car OFF.

You can also manually move the shaft around a bit to see if there is give.

the disc is like a rubber washer. A disc-form.

do a search of archives for specifics!

good luck.

__________________
1979 300D 220 K miles
1995 C280 109 K miles
1992 Cadillac Eldorado Touring Coupe 57K miles SOLD
********************
1979 240D 140Kmiles (bought for parents) *SOLD.
SAN FRANCISCO/(*San Diego)
1989 300SE 148 K miles *SOLD

You should be able to see the rear flex disk when you're lying down from behind the car. Its a big round rubber disk that connects the drive shaft to the differential.

__________________
"spreading a trail of obnoxious where ever we go"
1981 300sd w/ 341,500 miles

http://www.wecrash.com/pics/ddda_banner.gif

Here's an easy way to tell....can you push/roll the car along with it in park? If so, then the connection between transmission and wheels is no longer present. Its probably hard to see the flex discs on a W124, its probably all tucked up underneath vs on a W123 or W126 where its more in the open...

__________________
-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)

oops, I was visualizing it on my car so I guess I just figured it was a w123 or w126

__________________
"spreading a trail of obnoxious where ever we go"
1981 300sd w/ 341,500 miles

http://www.wecrash.com/pics/ddda_banner.gif

I can push the car while it is in park. I need to raise the car in order to examine the flex discs fully. The question is.....if the transmission is disconnected from the driveshaft, what's next?

__________________
k. darkman
1987 300D Turbo 200k