'81 300D, 5-10MPH Wreck, motor mounts busted, trans mount too... - Page 2 - PeachParts Mercedes-Benz Forum

i-osprey · #16 11-28-2007, 01:05 PM

You were right on the money junqueyardjim.

Separation occurred in the driveshaft just aft of the transmission and before the carrier bearing.

Any advice on getting everything back where it belongs would be greatly appreciated. I have jack stands and a hydraulic jack on wheels. I also have an assortment of pry bars at my disposal...

I am afraid to look at the accelerator linkages. I know for a fact that one was very taxed. I am also worried about the shifter linkage.

junqueyardjim · #17 11-28-2007, 01:19 PM

Check them out visually. You'll see it quick if they are gone. The small section we see in the picture the rubber looks pretty good, unless there might be a crack in the rubber. These flex joints have to transmit all the power in your Benz, so they do wear out once in a while. From what I see of the front one, they look pretty good. You might want to check the slip section of the drive shaft right behind the transmission. Your engine/transmission is already moved forward about 4 inches. I think that spline joint will separate about 6 inches before it separates. If it separates, you want to be able to slip it back together in exactly the same position to retain the factory established balance. To do that, it might be wise to mark both side of the joint with a small dab of white paint in line with each other. Do this before they come apart.

i-osprey · #18 11-28-2007, 02:18 PM

Well, it separated. And it was in gear when I had the wreck so I assume that keeping it balanced is a shot in the dark.

I also noticed that the left side of the engine/tranny shifted more forward than the right side but no more than an inch or two.

What are my chances of getting it all balanced again?

junqueyardjim · #19 11-28-2007, 06:21 PM

I recall reading that beginning on 82 models they were marked with an arrow or a line on each part. I remember I found it on my 84. It's dark and cold out now, so I will check for that mark tomorrow. Also, check the two pieces for marks another mechanic or PO might have made on it.

i-osprey · #20 11-28-2007, 09:34 PM

Quote:

Originally Posted by junqueyardjim

I recall reading that beginning on 82 models they were marked with an arrow or a line on each part. I remember I found it on my 84. It's dark and cold out now, so I will check for that mark tomorrow. Also, check the two pieces for marks another mechanic or PO might have made on it.

Will do. Which is easier to turn, the transmission end or the rear-end end? Would jacking up the rear end be easiest so the wheels could turn?

This job seems pretty straightforward I just would like to shorten it as much as possible, if possible.

Thanks

i-osprey · #21 12-01-2007, 08:49 PM

I replaced the motor and tranny mounts today and it was amazing. I think I could probably stand a nickel on its edge and it would stay there with the engine running.

I re-attached the driveshaft and maybe by blind luck I got it pretty close. I do detect a slight buzz at about 65-70 mph but it may have always been there.

My flex disks are toast, especially the front one. Unfortunately, I didn't order them in time to put them on today. So I am going to have to do this all again when they come in.

I would have waited but I really need the car on Monday and the disks won't be here by then.

I wil have to pussy foot it around town and no downshifting for sure. I can't believe I was driving it like I was with the flex disks in their condition. The rear one just has visible cracking but the front one has cracking and some thread showing in a couple of places.

I am a little worried about driving it as is but I don't have a choice.

I will replace the center bearing and bracket as well when they all get here.

The motor mounts made a huge difference. I now know what the thunking was when I applied the brakes. No more thunking now.

junqueyardjim · #22 12-01-2007, 09:30 PM

Those flex disc are really tough. And they are just as good now as before the accident, well let's say about as good. But they will have to be replaced. Good luck and keep us informed.