Strange Manual Transmission Behavior - PeachParts Mercedes-Benz Forum

DieselPaul · #1 12-02-2013, 02:11 PM

I have been having some strange transmission issues with my 200TD.

Its a '87 200TD but it has a 230TE diff (3.65) and a gas transmission because of a supposedly taller overdrive (.78 vs like .82 or something). I did not put the car together. The car does get killer gas mileage, and is 240D slow. The trans was put in around 70,000 miles ago, miles on the trans are unknown, it got a new clutch at the time.

If I remember correctly when I was under the car it is a 717.412.

When the car is cold the shift from 1-2 grinds. If you double clutch it makes it easier to shift. However if you get on the highway and run for a while in fifth, get the car warmed up, the 1-2 shift is much smoother.

Occasionally sitting at a stop, clutch on the floor, shift into 1st it will grind into first.

The clutch is periodically grabby, hard to describe but it just doesn't feel right.

Parked on a slight incline the car will start to roll away but it like shudders and jerks, more like the clutch is slipping, not the motor is turning over because of low compression.

If you let the clutch out quickly on the 1-2 shift the car bucks and shakes the hell out of the car.

The car occasionally is hard to get into first gear when its running, shifting into second then up into first helps get in easier.

So far I've bled the clutch with a power bleeder, then gravity bled it.

Changed to synthetic Dex3

Changed back to conventional Dex3 for my own curiousity

Put in an bled a new FTE master cylinder and slave cylinder from Pelican.

I inspected the shift bushings on the transmission and on the ends of the shift rods, they aren't brand new, but none are missing or obviously ovaled out. I have some brand new ones I bought with the clutch hydraulics so I will replace them soon regardless.

So!

Would a bad clutch make the car hard to shift?

The fact that it gets somewhat better when the car is hot is weird, but the not holding on hills and the bucking (which I may be unaware is clutch chatter?) lead to me to believe the clutch itself is bad. 70,000 miles on the clutch means its far from brand new, but with 75HP I would have thought the clutch would last longer. Though I do know my friend I bought it from drove the car in the city a lot.

I noticed the car has what I've seen is a factory Mercedes part, a thin plastic spacer between the slave cylinder and the transmission housing. Do all of the cars use a spacer?

compu_85 · #2 12-02-2013, 02:15 PM

I'd think the 2nd gear syncro is worn. I'd try some Pensoil Syncromesh fluid and see if it improves things.

-J

DieselPaul · #3 12-02-2013, 02:17 PM

I wouldn't be surprised that second is worn, I was sort of thinking the trans getting hot may have something to do with the syncro working better.

I've never seen anyone put Syncromesh in a Mercedes trans. That is what I used to put in GM transmissions, will it work in the 717?

tjts1 · #4 12-02-2013, 02:33 PM

Is the gearbox out of a W124 or W201? If its from a W201, the shift rods are slightly shorter and need to be lengthened in order to fit the W124 body. If they haven't been lengthened you might not be engaging second gear fully.

What kind of mileage are you getting out of it? I bet you have the only OM601 powered S124 in the country. Does it have wind up windows and cloth seats? Any pics? The car sounds interesting. I think the early 124 200d/td only had a 4 speed manual from the factory so a 5 speed should be a nice improvement.

DieselPaul · #5 12-02-2013, 02:41 PM

The shift rods still have Mercedes Benz stickers on them from the dealership and they are 124 part numbers.

Most tanks are 37mpg combined. Highway trips to Cincinnati are around 43mpg.

It has MB Tex, power front windows, crank rear. I have a Euro 190E 2.0L with Cloth interior, power front windows, crank rear.

tjts1 · #6 12-02-2013, 02:54 PM

Cool, that sounds like a very unique combination and excellent fuel economy. Sorry I can't help with the shifting issue. Maybe try Redline MTL or MT90 in it. MTL helped improve a similar shifting issue I had on a BMW E30. It sounds like worn out syncro.
good luck

t walgamuth · #7 12-02-2013, 03:51 PM

If you sit at a light with the clutch in does the car start to take off? If so you have a internal leak in the clutch master. Some of your symptoms might support this theory.

A high mileage tranny with worn synchros can be run for many years more if you just take your time shifting up and if down shifting either double clutch or just wait til the engine is turning low rpm and the car is not going very fast.

People had to drive this way all the time until the fifties and sixties when synchro became common. (I learned to drive on a no synchro rambler american, 59 model, so I knew how to double clutch before I had a license

)

winmutt · #8 12-02-2013, 04:56 PM

You have a strange car, be prepared for strange issues !

DieselPaul · #9 12-03-2013, 10:31 AM

Quote:

Originally Posted by t walgamuth

If you sit at a light with the clutch in does the car start to take off? If so you have a internal leak in the clutch master. Some of your symptoms might support this theory.

Car doesn't creep at redlights.

The problem is weirdly inconsistent and when I bought the car in the summer it acted perfectly fine. So maybe this spring it'll get better again when the car isn't so cold.

I'm still not totally convinced the clutch itself isn't partially to blame.

I had really good luck with syncromesh fluid in GM transmission in winter, reading about it syncromesh is basically 5w30 with additives, but that's why it does well in cold weather. If I get bored and have $20 around I may give that a shot.

I read stretch's how to rebuild a 717.412 thread, I've redone a 4speed in a G-wagon before and it wasn't too too bad, so that's a consideration at some point too.

Here are some pics

bricktron · #10 12-03-2013, 11:36 AM

at least on manual W123s, the spacer between the slave and transmission allows a special feeler tool to measure clutch wear.

i also have that occasional grinding into 2nd, when i shift quickly. will have to try one of the fluids mentioned here.

charmalu · #11 12-03-2013, 12:51 PM

Here is some interesting reading.

Replace clutch slave cylinder and bleed clutch

Grinding into Reverse!

my 240d's clutch will not engage!

78 240D Clutch Chatter

Clutch master cylinder question W201 & 124.

Clutch Wear Gauge

Charlie

tjts1 · #12 12-03-2013, 04:09 PM

That thing looks great, dig the hub caps. My diesel is slow with twice the power, I can only imagine what the OM601 is like.

DieselPaul · #13 12-03-2013, 04:14 PM

Slow, but I think its faster than a 240D, my father has a 240D, he wants to have a race, so I'll be sure to post the results. My euro 190E is getting the cladding repainted from years of parallel parking damage in Madrid. When I get it back I'll take some better pictures of both cars together.

If you look at my sig I've got a lot of slow cars so it does not really bother me. Its funny to drive the 200TD around and then get in the 190SL. 190SL feels like a rocketship.

It's more than likely the only one in the US, so its novelty outweighs its lack of performance. But I travel back and forth between Columbus and Cincinnati a LOT, and move a lot of parts. With working SLS, and 5th gear it'll run 85MPH smooth and get 43mpg with a trunk full of crap. So if you take a holistic look at "performance" it serves my purposes very well.

Plus, its just so damn cool.

t walgamuth · #14 12-03-2013, 04:16 PM

I agree. Cool!

tjts1 · #15 12-03-2013, 04:54 PM

Quote:

Originally Posted by DieselPaul

With working SLS, and 5th gear it'll run 85MPH smooth and get 43mpg with a trunk full of crap. So if you take a holistic look at "performance" it serves my purposes very well.

Plus, its just so damn cool.

I like it. I think with a turbo and taller diff it could be even more efficient. If the 300d turbo 5spd can average 41.8mpg over a 951 mile stretch, the 200td turbo should do a lot better. Maybe a 3.27 diff with a small turbo. I kind of wish I had found a 4 or 5 cyl W124 just for the extra room in the engine bay.