I just recently bought a 83 300D Turbo. It was running quite well. Then three weeks later, the transmission won't engage no matter which gear I put it in. It stays on park.

Let me give you a bit more background:

This all started during a 400 miles trip I took. After I drive on the highway for a bit and then stop for diesel, sometimes the transmission won't engage for a minute, but when it finally engaged it worked fine, no delay.

After the trip this non-engagement symptoms appeared sporadically two or three times. Usually I just need to turn off the car and turn it on again, and then the transmission will work with no delay.

Then one day, I used the car to jump another car's battery. I had to step on the acceleration in park for about 20 mins (It was charging very slow.) Onces the charging was done, I turned off the car and started it again. Now the transmission won't engage for a seriously long time. I had to pushed it to the parking lot, tried to drive it a few times in the next four hours.

I decided to check the transmission fluid finally (not sure why I didn't do this before), and found that it was low. Filled it back up, waited for another 30 minutes, and it worked. In fact, the typical jerk between 1st and 2nd gear was gone too. But I did notice a knock when I slowed down the car to a stop (maybe from down-shifting?)

However, the next day and here after, the transmission would not engage at all. I do get lucky sometimes to get it engage every 3 hours but then it stopped working as soon as shift to park and back to drive.

I went to the mechanics and talked to a transmission shop, both told me that it's probably something serious and won't be even worth it to fix (compared to buying another car). Though I feel like they didn't check anything.

The color of the fluid was not perfect, it was a bit dark on a white cloth, but there's no visible particles.

What should I do? The car was $1500 and need axle change and oil leak fixed which may cost another $1500. If the transmission is completely gone, I feel there's no reason to spend any money on it.

But I'm thinking if it's an easy fix I can still get it running and sell it to the buy back program for $1000

Thanks in advance.

 

Try changing the fluid and FILTER. Then ontop of the valve cover is a black cover with one screw holding it on, take it off and look where the half moon linkage rubs agaist the valves (plastic little things with a bunch of vacuum hoses on it) there is two levers that go inbetween the half moon thing and the valves, these wear out and yours are more than likely worn out and need to be replaced. Try this link: http://dieselgiant.com/diesel_parts_...alve Lever kit Vacuum Valve Lever kit

 

Thanks wreck79. I'm asking my mechanic to do a transmission service, which include flushing the transmission, new fuild, filter, adjusting the vaccum, band, etc. I hope that will do the trick.

Really at this point, if I can get my car to drive even just for one day, I can sell it to the buy back program sponsored by the state. And that will be better than nothing.

 

What state are you in, and how much will they give you for the trade in ?

 

In California, there are two programs:
http://www.baaqmd.gov/Divisions/Stra...k-Program.aspx
http://www.smogcheck.ca.gov/
both will pay $1000 for your car.

 

Old thread.
Part of it sounds like you're having a B2 piston issue but when that happens revers is still supposed to work.

I had an issue where I had to rev the engine to get it to go forward. That went on for a few months. I changed the fluid and the filter and not quite a year later the B2 piston broke, and I lost forward movement entirely.

In order to verify it is the B2 piston you need to take it out and that is not what I would say is easy on a 1984 Mercedes 300D. On a Mercedes SD there is a lot of room but not on mine.

Another thing that can happen is the B2 piston band can crack and have the same symptoms. So you need to verify the band is not cracked as best you can. The band is inside of the transmission so that would need to be rebuilt.
More than that is beyond my experience.