OK, still trying to get the tranny to stop flaring from 1-2 and 2-3. I’m in third by 20mph, and can’t get out of anyones way. I spent 3 hours in the search area last night, but all the info that I find doesn’t seem to cover this type of linkage. (’80 300TD) From my crude edited picture, vac line A is from “Tee” on vac line from pump to brake booster. I have no Mity Vac, but it has tons of vacuum. Vac line B goes to brown plastic air line down to tranny. When engine is idling, no vacuum out of B. As engine rpm’s increase, vacuum increases. At the green arrow is a small metal tab that goes into plastic housing that the vacuum lines come out of. The movement of the accelerator causes the cam on that linkage to push in the metal tab, which in turn allows vacuum into the line. From what I’ve read, vacuum makes tranny shift, so if I have full vacuum I’m guessing that is the reason for the early shifting and flaring. I swapped vac line A with the question mark line, and it shifted the same. I unplugged the vac line to the tranny and the car went forever in first, then rocketed into second at about 20mpg, replete with headsnap. Never shifted out of second and the rpms were getting so high I lost courage. These cars DO actually have some pickup afterall. Wouldn’t turn off until I reconnected the vac line to tranny, by the way.
Anyway, I’m stuck as to what I need to do to get this adjusted correctly. And something I will ask much later, I see nothing that would be a kickdown.
I want to get this working so badly! I would appreciate some help, or point me to a thread I may have missed. This car has potential, but the entire driving experience is lost with this tranny situation.
Thank you so much,
Jimmy Layton

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__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

Alot of what I read spoke of something on back of IP for the tranny vacuum. Vac line from IP goes into the firewall and I haven't determined where it goes, just that it is different from the archived threads I found.

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__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

The brown w/blue strip line is going to the kill switch on your ignition.

__________________
'84 300CD Turbo 132k (Anthracite Grey) - WVO - My daily driver - Recently named coo-coo-coupe by my daughter.
'84 300D Turbo 240k (Anthracite Grey) - Garage Queen
'83 300D Turbo 220k (Orient Red) - WVO - Wifes daily driver

I'm not a certified mechanic, but I did stay at a HolidayInn Express last night.

Why don't you do a search for ' trans-x' ? Might help, about $20 lost if it doesn't... has helped many people.... not a snake oil... dissolves varnish built up in your trans control body. Won't hurt to try it.

I'm assuming that you have a 722.118 trans. (300TD early version). If not, might still be of interest.

Check here for some info.: http://www.mercedesdismantlers.com/AutomaticTransmissionInformation.html

__________________
The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)

I had already tried the Trans-X, which seemed to help it shift from first to second better. But since my original post I fixed the problem, and here is basically how it went.
I first tried adjusting the modulator on the tranny (passenger side on my car, which was different than most of the archived posts that I was referencing). I adjusted the middle metal tab both clockwise and counter-clockwise. It changed certain characteristics of the shifting, but not all of the gear changes were as they were supposed to be.
I then reversed the vacuum lines. I switched the vac line from the "T" from pump/brakebooster line ['A' in picture], to where the 'B' line was plugged. The 'B' line went to where the stubby plugged line went, and the stubby went to where 'A' started out. This reduced vacuum under acceleration, and increased it at idle. I then adjusted the tranny modulator until I got it to shift correctly. It was interesting. There are quite a few notches in the modulator assy in one full 360 degree rotation of the adjustment piece, and it adjusted down to where there was an obvious difference between the place I adjusted it to, and the places on either side. By the way, I would drive up on ramps, make an adjustment, back off of ramps, drive down the road a piece, come back, drive up on ramps......... Not ONE TIME less than 20 times I bet.
But for the last 2 weeks I have actually been able to tell what these cars are like to drive [non-turbo, that is]. I opted for the slightly harder shift position over the slightly too soft shift position, and these trannys really rocket you into gear with a little RPM included. Between fixing the shifting and 2 new front tires, I could not be much happier at this time with my MB driving experience! It's really nice to be contemplating tinting the windows and not fixing something that is currently broken.
Yes, I knocked on wood....
JL

By the way, JamesStein, thanks for the info on vac line. Wasn't using my head when I looked at that line.

One more question as I keep editing this, Is my vacuum/linkage situation on my '80 300TD a rather obscure setup compared to what most 300's have?

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John