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Discussion Starter #1
I am swapping motors and transmission for my 82 300D. The motor/tran that I am switching it out with is from a wreck. It was hit on the passenger rear side. Axles appear to be fine, no visible damage. They spin correctly when in drive or neutral. And lock in place when in park.

However the transmission does not respond unless the driver side rear wheel is off the ground. With the wheel off the ground it spins flawlessly. But as soon as I lower the car, no response, doesn't even budge.

Any clues?
 

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2003 Volvo V70 5 Speed
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fluid level?
 

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-1985 300d (champagne/palomino 133k) -1979 300d (dead parts car)
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128 Posts
i have no idea. you just asked for guesses :) sorry, man!

i don't know trannies all that well.
 

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Discussion Starter #11
So I finally spent some time on the car. The first thing I noticed was the grommet on the linkage was worn out, it still shifts but takes a little effort. So I just got under the car and shifted it from underneath.

I got the wheel moving pretty fast and lowered the jack with the wheel rotating. When it hit the ground it continued to spin and I was able to drive it around. I couldn't take it on the road but I figured I got it up to 35mph. But as soon as I come to a complete stop the wheels cannot be turned again unless I jack it up. So it appears that first gear isn't engaging, nor is reverse.

What could that mean, a bad b2 piston?

Eventually I will just pull the transmission, but I don't want to go through the trouble if it's not worth it.
 

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2003 Volvo V70 5 Speed
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hmmm.... well if the shift grommets are worn maybe it's not staying completely in gear? This is an odd one. When you check the fluid you are doing it with the engine running correct? But if you think the tranny is the issue it might be easiest to just swap in the other tranny you have...
 

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Discussion Starter #13
hmmm.... well if the shift grommets are worn maybe it's not staying completely in gear? This is an odd one. When you check the fluid you are doing it with the engine running correct? But if you think the tranny is the issue it might be easiest to just swap in the other tranny you have...
Yes I checked the fluid levels with it running, no smell, no odd color and the level is on the money.

If I shift it from inside it won't shift correctly, so I have been getting under it and shifting it into gear with a pair of pliers.

And this is the transmission from the car that was wrecked. My car already has a bad transmissions, so if this one is bad I will have to find a new one. I am assuming this one is fine. It was in a wreck, so it was running when it got hit. The axles are in good condition as well so I don't suspect it was bind up in the accident. It feels as if it's just frozen up.

I think my next step as soon as it warms up is to replace the filter and see if it has any shavings.
 

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Discussion Starter #15
with these cars. what looks like a tranny issue is actually a vacuum issue.
Correct me if I am wrong but the vacuum only controls the speed in which the gears change, not the actual mechanism of shifting? It should still shift even with no vacuum, and should go into first.

When the transmission receives a vacuum it shifts normally, and soft. But when you apply a lot of throttle the vacuum is open so it will shift faster. So what happens when you have low or no vacuum the transmission will constantly shift hard, like you are flooring it.

Unless I am wrong about that, which is possible. The modulator needs to be replaced, but I won't worry about it until I know this transmission can at least move the wheels on the ground.
 

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Discussion Starter #16
So I think the best solution is to run a transmission treatment of some kind. My guess is the fluid has just turned stiff around the first gear. Once I run the treatment I will flush the system.

The question is, what is the best/safest solvent or treatment to use?
 

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2001 Volvo V40
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What is not entirely clear to me is whether you've exchanged transmissions or are you checking the engine and transmission of the accident-damaged car?

If one wheel is of the ground, there is no resistance and the engine can rev freely (just like when it is in Neutral). If there is no power when both wheels are on the ground, the transmission is severely worn-out or the torque converter has not been installed properly (that only happens when you take the torque converter from the transmission).

Vacuum controls oil pressure in the transmission, but vacuum problems are not enough to rob the transmission of power. On certain non-turbo models it also controls (also by oil pressure) the shift points as well as the shift quality. The 1982 300D is a turbodiesel right?
 

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Discussion Starter #18
What is not entirely clear to me is whether you've exchanged transmissions or are you checking the engine and transmission of the accident-damaged car?

If one wheel is of the ground, there is no resistance and the engine can rev freely (just like when it is in Neutral). If there is no power when both wheels are on the ground, the transmission is severely worn-out or the torque converter has not been installed properly (that only happens when you take the torque converter from the transmission).

Vacuum controls oil pressure in the transmission, but vacuum problems are not enough to rob the transmission of power. On certain non-turbo models it also controls (also by oil pressure) the shift points as well as the shift quality. The 1982 300D is a turbodiesel right?
No I have not exchanged the transmission. Currently the wreck still has it's motor and transmission. My plan is to swap both my motor and my transmission. The motor in the wreck is in great shape( yes the 82 is a turbo), the transmission is the question mark. So before I take out both motor and tranny I want to make sure it works. I assume it should work, due to the fact that it was involved in an accident, so it was running up until that point. The accident it was involved in was not serious, he was hit on the rear passenger side, it just damaged the trunk. The wheels and axles work freely.

So here is what happens. When I lift one wheel off the ground I can get it up to speed, it shifts great, and I've gotten the speedometer up to 60(then I got nervous and let off the gas) I understand it isn't receiving much friction. However I have lowered the car while spinning the wheel and was able to drive it on my dirt road, for a good ten minutes. As long as I kept my foot on the gas the car would speed up and slow down. I was able to take it from 0-45mph, could have gone faster, but not enough road. So the transmission is receiving power and transferring it to the wheel. And from what I understand about these transmission is they stay in second gear unless you completely come to a full stop. So to me it's acting as if 1st gear is frozen up.... But it could simply be a bad transmission, I just hate to give up on it do to the fact that once I get it moving it works great.
 

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The transmission idles in second gear, but shifts back to first gear as soon as you press the accelerator pedal. Does it lack power in L, S and R too? or just in D?

You can try pulling off the vacuum line to the transmission, see if that changes something.

Maybe a long shot, but could it be the differential is damaged and that no power can be transmitted through it? Was the rear wheel hit?
 

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Discussion Starter #20
I have not gotten it into R, the bushing is missing on the linkage, so I am never sure what gear I am in, however as soon as I move the stick into any position other than P it does supply power to the wheel, as long as it is off the ground. This afternoon I had the wheel spinning for about an hour and then lowered it. Once lowered it did budge the car(about half an inch), which it's never done before.

I am pretty sure the differential is fine.. I've lifted both sides up and checked to see if they moved in R,N,D,S,L and locked in P. Which they did. I wold assume if there was damage in the rear end it would move freely in park.

I will try the vacuum out tomorrow, if it would help I can post a video of it on youtube so you can see what the wheels are doing.

I appreciate the input.
 
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