HELP ME PLEASE!!! Is my tranny broken??? - Page 2 - PeachParts Mercedes-Benz Forum

vstech · #16 06-08-2010, 01:12 PM

first off, an vacuum leak would cause soft shifts not hard ones.
it could be the kickdown switch still. just because it seems ok dosen't mean it is.
disconnect it, and see if it's working. if you disconnect it completely, drive and see if it shifts correctly.

tobybul · #17 06-08-2010, 08:57 PM

take pictures of the engine compartment and post it.

RichardLSU · #18 06-09-2010, 12:52 PM

Ok, I'll get to it today.

RichardLSU · #19 06-09-2010, 08:08 PM

Ok, I'm not really sure what it is you are looking for so I got both sides of the engine bay. I put my finger under the Bowden cable to show it isn't broken and I took a picture of that white bolt I was talking about.

I took it for another spin today and its just having a hard time shifting up into second and from second to third. It does shift, most of the time, but only at really high rpms.

RichardLSU · #20 06-10-2010, 10:05 AM

I managed to find a vacuum diagram. Is this one correct for my car? Apparently alot of things changed in 85'. Again, where do I begin guys?

vstech · #21 06-10-2010, 10:22 AM

did you unplug the kickdown switch and take it for a drive?

RichardLSU · #22 06-12-2010, 12:30 AM

Yes, it didn't make a difference.

tobybul · #23 06-12-2010, 09:13 AM

Quote:

Originally Posted by RichardLSU

I managed to find a vacuum diagram. Is this one correct for my car? Apparently alot of things changed in 85'. Again, where do I begin guys?

try tracing the vac lines startng from the vac pump (67). Make sure there are no breaks and the fittings are tight. Generally, 1985 models have good vacuum since MB recognized the issues on previous models. Most f the lines are on the driver's side of the engine except for the line that goes to the egr.

RichardLSU · #24 06-12-2010, 11:32 AM

Well its raining like crazy right now, if it clears up I'll start on it. Again, thanks so much for all ya'll's help!

okyoureabeast · #25 06-12-2010, 11:43 AM

My 85 had a small vacuum leak that took me a bit of time to isolate.

First off start isolating vacuum connections in the engine compartment. In my case my leak was in the small rubber diaphragm in the front passenger door lock.

A mity vac is very helpful and will be your best friend in the near and distant future.

RichC · #26 06-12-2010, 11:44 AM

vacuum leak

bowden cable

Those are my guesses.

my123ca · #27 06-12-2010, 12:54 PM

Quote:

Originally Posted by vstech

first off, an vacuum leak would cause soft shifts not hard ones.
it could be the kickdown switch still. just because it seems ok dosen't mean it is.
disconnect it, and see if it's working. if you disconnect it completely, drive and see if it shifts correctly.

A vacuum leak will cause hard shifts.

Could be the kickdown switch. How many miles on the tranny?

hobberslobbers · #28 06-12-2010, 07:15 PM

richard, try this to rule out a vacuum leak. it's cheap (free) to do and will help isolate where you need to go next. here you go. find the single/sole vacuum line which goes to the transmission and pull it out of the rubber connector near the driver's side engine compartment. this line is a hard line and is typically black and routes, on most diesels, between the rear of the valve cover and the firewall. make sure you only disconnect this 1 line and make sure it is the one going to the transmission. then, go for a drive. your car should shift "hard" but it shouldn't over rev like what you have described above. when coming to a stop, with the line disconnected, the 3-2 downshift will be clunky/jerky, but should be crisp. report back your results. remember, all we're trying to do here is to isolate whether you have a vacuum problem. also, check all hard plastic line connections of all other vacuum lines and make sure none are disconnected (or broken). a detailed pic of the driver's side of the engine with all the vac lines included would be helpful.

RichardLSU · #29 06-13-2010, 10:43 AM

My father has a friend that runs an Aamco transmission shop here in KCK. I took it down to him and he hooked up a vacuum pump to my car and pumped it up, took it for a drive and it shifted like it was brand new. He said the problem is that the transmission is getting zero vacuum pressure, and since diesels don't really make vacuum I should take it to a diesel tech to isolate the problem.

Are all of the vacuum systems connected? (like with the door locks?) My locks haven't worked for quite some time unless I manually lock and unlock each door.

I'll get a detailed pic of the drivers side of the engine today and post it.

tobybul · #30 06-13-2010, 11:17 AM

Quote:

Originally Posted by RichardLSU

My father has a friend that runs an Aamco transmission shop here in KCK. I took it down to him and he hooked up a vacuum pump to my car and pumped it up, took it for a drive and it shifted like it was brand new. He said the problem is that the transmission is getting zero vacuum pressure, and since diesels don't really make vacuum I should take it to a diesel tech to isolate the problem.

Are all of the vacuum systems connected? (like with the door locks?) My locks haven't worked for quite some time unless I manually lock and unlock each door.

I'll get a detailed pic of the drivers side of the engine today and post it.

Vacuum leaks anywhere in the car could affect tranny shifting. I believe you have just confirmed that you have a leak somewhere. With a Mity Vac pump, you should be able to isolate the problem. There is a very good DIY link in this forum on checking vacuum pressure on the tranny line. IIRC, you are suppose to get 21-23 in Hg in this line.

http://www.peachparts.com/Wikka/TransVacTune

I'm glad the tranny shop did not say that you need to change your tranny. Many of them tend to write off the tranny b/c they are not familiar with the MBs. Kudos to your Dad's friend.