Transmission mission. Can we fix it?

[troytrinkle]

Hey Transmission Gurus,

I've got one for you. I recently bought a 1985 190d with 2.2 engine mated to a 722.403 transmission. It had shifting problems when I bought it, and it was cheap. How could I go wrong? Transmission are just machines. We fix machines everyday.

All of the information I'll share with you has been gathered during the last few weeks as I've educated myself through forum articles and some aftermarket service litature. I humbly present myself as a novice with a stubborn need to fix the machine.

The problem presented itself as flaring between 3-4. The car would drive and shift well until it shifted to 4th gear then nothing but a racing engine. With the guidance from articles presented by Steve Brotherton and Diesel Dan, I have narrowed it down.

Here's what I know:

1. I have great vacuum and no leaks.

2. I have no play in my kick down cable and it doesn't hang.

3. I have good modulator pressure.

(I think Dan had more room under his w123 shown in his Wiki article. Testing the transmission pressure of my 201 model was a trick. I had to drop the rear mount to get at the test port. I also found an alternative to using a banjo bolt for tapping the test ports. I used a 1/4" nylon hose barb. I just threaded it and stuck it in. However, the banjo bolt would have worked much better, but parts options on a Sunday afternoon is limited. Lowe's was my only choice.)

I had 2.8 bars of pressure when I cranked the modulator all the way in. Which was only an increase .2 bar through full adjustment. However, 2.8 is what my data sheet called for.

During the road test I felt the car kick into 4th gear. This was very encouraging, but it would slip when ever I stepped on the throttle. However, when I reconnected the vacuum to the modulator valve, I lost 4th gear altogether. I flarred from 3rd gear.

The ATSG book has a remedy, but their info isn't sound enough for me. I've found thier manual useful, but a little messy. However, this is what they say to do when your tranny slips during 3-4 shift:
1. Adjust the modulator. (done that)
2. Change the shift valve housing. (which one and what housing)
3. Recondition the K2 plates. (I might pass on that)

Ok. So there's the skinny. What do I do now?