Finding a real FSM for Trans NEED HELP! - PeachParts Mercedes-Benz Forum

Ian White · #1 03-02-2009, 10:55 PM

With the loose shifts and flares I am having between 2-3, and 3-4 and since I cannot figure this out easily. I am in need of a factory transmission service manual. The problem started suddenly and I have tried re-adjusting everything. The only thing I have not done is the K-1 spring kit or the B-2 Band thing. I would love to get this resolved, as my beloved BENZ is getting on my nerves!
And I really don't want to have to pay a trans shop to fix something that could be an easy fix.

Thanks for the consideration,

sixto · #2 03-02-2009, 11:05 PM

If you're sure you're getting a proper vacuum signal to the modulator, the modulator isn't leaking (e.g., drawing ATF into the VSV) and the bowden cable is adjusted correctly, I suggest you look into a Superior shift kit -

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=260116350141

There are a couple of long threads from the October 2008 timeframe that discuss installation and results. Spring tuning won't overcome vacuum problems and makes the transmission very sensitive to bowden cable setting.

edit - Make sure there's a cap over the modulator adjustment handle.

Sixto
87 300D

Ian White · #3 03-02-2009, 11:13 PM

okay what hg should I have there? and what does the trans dashpot do? i have one but dont know what it does. Would the lack of vacuum to the trans result in the slow shifts into 3rd and 4th under heavy throttle? at lower levels of throt. it shifts okay a bit harsh though. If that is the case I need a vacuum diagram of the entire vacuum system and how it relates to the trans.

Thanks so much for the help!

sixto · #4 03-02-2009, 11:20 PM

One of the stickies is chock full of vacuum diagrams.

The bowden cable affect shift timing. If the shifts occur when you expect, don't touch the cable.

Vacuum affects shift firmness - more vacuum means softer shifts. The VCV mimics manifold vacuum in a gasser. The VCV linked to the throttle linkage to the IP varies vacuum from what the pump puts out, about 20" Hg, to nothing under WOT. You can test this with a MityVac, vacuum gauge and your hand on the throttle linkage. Engine running or not, your choice

Sixto
87 300D

Diesel911 · #5 03-02-2009, 11:23 PM

I have yet to here of a good transmission Manual I wish someone could find one also.

http://www.continentalimports.com/ser_ic20242.html

Transmission:

Ian White · #6 03-02-2009, 11:39 PM

Quote:

Originally Posted by sixto

One of the stickies is chock full of vacuum diagrams.

The bowden cable affect shift timing. If the shifts occur when you expect, don't touch the cable.

Vacuum affects shift firmness - more vacuum means softer shifts. The VCV mimics manifold vacuum in a gasser. The VCV linked to the throttle linkage to the IP varies vacuum from what the pump puts out, about 20" Hg, to nothing under WOT. You can test this with a MityVac, vacuum gauge and your hand on the throttle linkage. Engine running or not, your choice

Sixto
87 300D

So the VCV is the switch thing ontop of the valve cover? If so I replaced the little levers in there and saw an improvement. The problem I am having is a kinda slow shift from 2-3 under heavy throt. and worse flaring when its shifting from 3-4. It seems to shift fine though when not under heavy acceleration. tommorrow I will take pictures of the myrad of vacuum lines going everywhere maybe someone can point me in the right direction.

And on an unrelated topic. Where is the ALDA overboot protection switch located? And also When I went to change my ALDA, I loosed the outer nut, but the stud sticking up with s slot for a screwdriver wouldnot move almost like the retaining nut was still on it. I tried pretty hard untill the stud's slot barely started deforiming. Am I doing something wrong,

Thanks to all you BENZ addicts like me....

sixto · #7 03-03-2009, 12:00 AM

Fingers? We ain't got no fingers. We don' need no steenkin' fingers!

The VCV is the plastic pod behind the IP. I don't know if the vacuum lines go through the fingers. You'll have to check the vacuum diagrams for that.

The overboost switchover valve is on the firewall inboard of the brake booster. Follow the plastic line from the aft end of the manifold to the switchover vavle. Or follow it back from the ALDA.

You seem intent on wringing every last ounce of performance from your engine. Forget adjusting the ALDA and just remove it. Control exhaust smoke with your right foot. At least try it.

Sixto
87 300D

sixto · #8 03-03-2009, 12:06 AM

If it shifts better under low throttle, I'd guess the VCV isn't doing it's job to reduce vacuum under heavy throttle. Put a vacuum gauge on the line the transmission modulator and report back.

Sixto
87 300D

Ian White · #9 03-03-2009, 12:46 AM

Okay will do, what does VCV stand for? what should the vac readings be?

And yes, I am OCD on most things haha. Is your ALDA removed? Any knowledge on removing the ALDA? I will have picts tommorrow of the vacuum system.

Thanks a MILLION!

Ian White · #10 03-03-2009, 01:08 AM

vacuum line pics, more to come tomorrow.

Regards,

sixto · #11 03-03-2009, 01:09 AM

VCV = vacuum control valve

I don't know how to perform the base adjustment on that type of VCV and I can't find it in the archives and I don't see it in my FSM. Someone else will have to tell you.

The ALDA is held on the IP by a nut that takes a 24 or 27mm wrench. There are wrench flats on the bottom side of the ALDA above the locking nut or you can hold the main case of the ALDA. Get the nut loose and spin off the ALDA.

Sixto
87 300D

sixto · #12 03-03-2009, 01:11 AM

Sixto
87 300D

Ian White · #13 03-03-2009, 01:17 AM

Okay I will look elsewhere. Benzworld.org is junk compared to this forum. The other one is just a bunch of guys who swap picts of thier cars and are not interested in helping others out with the care of our beloved benzes!

But at any rate, I will post more picts tomorrow and see If I can find out how to adjust the VCV

Many Regards,

dieseldan44 · #14 03-03-2009, 09:57 AM

Forced, thanks! I added that to my archives.

Ian, I can tell you how to test the system, adjust the VCV and what to expect. PM me, it would be so much easier to describe over the phone.

dd

Phil · #15 03-03-2009, 10:50 AM

The 2-3 shift is controlled by the k-1 valve. Replace the k-1 spring kit then look on this site for "adjusting the transmission". There is a very good write up about it but first replace that spring, it's an easy diy. After you get that done then do the adjustments and it will probably take care of your issues. One thing, before you start adjusting get a vacuum guage. I got a vac guage and connected it in the line to the transmission then ran a line out under the hood and in the passanger side window with the gauge on the end so I could see what was happening when I tested it.

I just noticed a couple of posts down was the write up on adjusting the transmission. Here is the link
It's CRITICAL... how you set your transmission's vacuum system on your diesel MBZ...