Trans Rebuild Started
#16
Rog, he can swap the "T" handle to look like a manual's .
Has anyone yet swapped a manual handle to look like an auto...old thread question.
Go Glen Go...this is not going to be your first successfully mounted hurdle
Has anyone yet swapped a manual handle to look like an auto...old thread question.
Go Glen Go...this is not going to be your first successfully mounted hurdle
#17
Rennlist Member
Thread Starter
Thought about the 5 speed swap, hell if I was going don that path it would be for a 6 speed swap. Agree with you Roger, this is much better.
I used Adam's old thread with the pictures he took for disassembly, they are real good.
Tony, will post up as I start assembly, not much to show other than all the parts lined up on the bench. I have everything bagged and tagged. I go and look at it each day so I can remember how to put it together
The manuals are actually really good on all phases of this, great pictures. Biggest thing is to take time, check all pieces and clearances.
Assembling the O-rings back into the K1 drum and K1 piston and also the piston in the oil pump area were tricky, could easily tear one when putting back together. That has been the toughest part yet. Glad I was at my buddy's shop who has experience in some trans rebuilds, not a 928 but other experience was helpful.
I'll take some pics as I work on the valve body, hope to do it over the weekend.
I used Adam's old thread with the pictures he took for disassembly, they are real good.
Tony, will post up as I start assembly, not much to show other than all the parts lined up on the bench. I have everything bagged and tagged. I go and look at it each day so I can remember how to put it together
The manuals are actually really good on all phases of this, great pictures. Biggest thing is to take time, check all pieces and clearances.
Assembling the O-rings back into the K1 drum and K1 piston and also the piston in the oil pump area were tricky, could easily tear one when putting back together. That has been the toughest part yet. Glad I was at my buddy's shop who has experience in some trans rebuilds, not a 928 but other experience was helpful.
I'll take some pics as I work on the valve body, hope to do it over the weekend.
#21
Rennlist Member
Thread Starter
Started Valve Body Cleanup - May have a Problem
Started the cleanup of the valve body, posted it in a different thread - https://rennlist.com/forums/928-foru...l#post10827507.
There was a spring in the documentation I have, that wasn't in the valve body and not sure why. The documentation is a manual for the MB 722.3 and 722.4 trans by Automatic Transmission Service Group.
Here is the missing spring (in red), not sure if it is different in the 928 from the MB.
Will try to reach Greg Brown, any others ever dig into their valve bodies?
There was a spring in the documentation I have, that wasn't in the valve body and not sure why. The documentation is a manual for the MB 722.3 and 722.4 trans by Automatic Transmission Service Group.
Here is the missing spring (in red), not sure if it is different in the 928 from the MB.
Will try to reach Greg Brown, any others ever dig into their valve bodies?
#22
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Started the cleanup of the valve body, posted it in a different thread - https://rennlist.com/forums/928-foru...l#post10827507.
There was a spring in the documentation I have, that wasn't in the valve body and not sure why. The documentation is a manual for the MB 722.3 and 722.4 trans by Automatic Transmission Service Group.
Here is the missing spring (in red), not sure if it is different in the 928 from the MB.
Will try to reach Greg Brown, any others ever dig into their valve bodies?
There was a spring in the documentation I have, that wasn't in the valve body and not sure why. The documentation is a manual for the MB 722.3 and 722.4 trans by Automatic Transmission Service Group.
Here is the missing spring (in red), not sure if it is different in the 928 from the MB.
Will try to reach Greg Brown, any others ever dig into their valve bodies?
#23
Rennlist Member
Thread Starter
I don't know if there is a rebuild kit for them, I'm going to call Transtar and ask. There aren't any seals in the valve body. 18 check *****. The springs in the shift improver kit are not the same as the springs that are in the pic above, they are in the other half of the valve body.
#25
Rennlist Member
Thread Starter
Greg Brown replied to the valve body thread, mystery solved. 87 and earlier cars had a slug, the later cars have the spring, my documentation is from the later cars. One less thing to be concerned about, now just waiting for the last parts (thicker metal for K2 clutch to get it in spec, damping spring which was not installed on mine) to arrive and start reassembly.
#26
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
I don't know if there is a rebuild kit for them, I'm going to call Transtar and ask. There aren't any seals in the valve body. 18 check *****. The springs in the shift improver kit are not the same as the springs that are in the pic above, they are in the other half of the valve body.
If I recall it was white-ish in color? maybe im thinking of something else?
#27
Rennlist Member
Thread Starter
Tony, yes there are split Teflon seals on the pistons in the lower half of the valve body, the pieces you took out for the flare fix. There are no seals on the valves in the upper half of the valve body that are in the diagram I posted. Mine look like new.
#28
Rennlist Member
Thread Starter
Tony, I stopped by Transtar today, they don't have or know of a rebuild kit for the valve body. Sales guy there said seals would probably have to be bought through a MB dealer. Not sure if anyone on the list here knows any different.
#29
Rennlist Member
Thread Starter
Assembly Started
Made good progress yesterday and today in putting it back together. Installed all new friction plates in K1 and K2 drums with the help of my buddy in his repair shop, had a great tool to compress the springs and get the clutches apart.
Here are some pictures in various stages of assembly
Guts going back in
New B2 band and valve, the band, valve and support should all be changed at the same time.
Ready to install governor and secondary pump
Parking pawl, governor and secondary pump installed
Ready for B1 piston
Ready for lower cover and plate
Lower cover installed and ready for valve body
Valve Body Installed - almost, 3 of the bolts threads looked funky, will replace them tomorrow.
So far, it has been fun and educational.
There are 4 different pins for the B2 system and the longest possible pin was installed. Taking the measurements according to the manual, I had to use the shortest pin available with the new band and valve. Makes me believe when the trans was rebuilt, the B2 band wasn't changed and the longest pin was needed to get it within spec. Almost confirms to me that the B2 band was never replaced in that rebuild.
Hoping to button everything up tomorrow and hopefully start putting it back under the car.
Here are some pictures in various stages of assembly
Guts going back in
New B2 band and valve, the band, valve and support should all be changed at the same time.
Ready to install governor and secondary pump
Parking pawl, governor and secondary pump installed
Ready for B1 piston
Ready for lower cover and plate
Lower cover installed and ready for valve body
Valve Body Installed - almost, 3 of the bolts threads looked funky, will replace them tomorrow.
So far, it has been fun and educational.
There are 4 different pins for the B2 system and the longest possible pin was installed. Taking the measurements according to the manual, I had to use the shortest pin available with the new band and valve. Makes me believe when the trans was rebuilt, the B2 band wasn't changed and the longest pin was needed to get it within spec. Almost confirms to me that the B2 band was never replaced in that rebuild.
Hoping to button everything up tomorrow and hopefully start putting it back under the car.