Any 722.3 seals worth renewing whilst out?

[JC220]

My S500 722.3 transmission is currently out and split from the motor.

Are there any seals or parts I should be replacing on the transmission whilst out and fully accessible? Not talking about a rebuild here! Just any common failure points that might be worth doing. 75k miles on the car.

Pan gasket, filter, new magnet, shifter brushings and new flex disc are being done. If any other seals that don't require special tools to replace I'd be keen to take care of it now.

 

[Duh_Vinci]

B1 and B2 seals and teflons at least, such pain to access when on the car! And yet such a simple replacement when out of the car!

 

[gsxr]

Re-seal EVERYTHING! The seals are cheap and it's simple with the box out of the car. Focus on the ones which are very difficult (or impossible) to do with the trans in the car, like the Bowden/control pressure cable, B1, and B2. Don't forget the selector shaft seal either, or the vac modulator.

I would do the front pump O-ring if possible, but this does require either fabricating some tools, or buying the proper ones. B2 is easy, B1 requires something to press in against the spring, if you don't have the tool. Use OE seals when possible, as you don't want to be repeating the work.

With only 75kmi, assuming it shifted OK and there was no unusual debris in the pan, I wouldn't worry about replacing hard parts.

 

[Duh_Vinci]

...B2 is easy, B1 requires something to press in against the spring, if you don't have the tool...

For B1 while off the car, I used the same tool this guy on 928 forum did, perfect "re-purpose" of wood working clamp!

 

[Duh_Vinci]

Speaking of "everything", saved this video post while back from Unkle Kent - everything "visual"

Regards,
D

 

[JC220]

Thanks to all for the tips and video! I will get a look at getting a list together for my trans. A full seal kit might be overkill.

I have never ran this transmission either. Car hasn't be running for many years and I bought it 6 months or so ago. Kind of wondering if I should just install as is to make sure its actually serviceable first. With the room in a C140 chassis it's not too difficult to pull the trans if need be.

Perhaps I'll just aim for easy / common seals as suggested and get it running to see what it's like.

 

[gsxr]

Don't get the full seal kit... it includes all the internal stuff you don't need, and it is not easy to tell which O-ring goes where, as almost nothing is marked/labeled within the kit. Just order each of the seals separately... takes a bit more time in the EPC, but they'll all be packed / labeled individually!

 

[JC220]

Thank to all for the input here - uncle Kent also keeps on giving:

I downloaded a ATSG manual for the 722.3 / 722.4 transmissions. First step will be to steam clean my trans externally to avoid dirt ingress during this work. I do see the Bowden cable is leaking fluid so all that will be taken care of. The NSS I might price and if semi reasonable renew it whilst the shift linkage is out for that seal like Kent's video.

I will be going through EPC and the rebuild manual to select only the seals I need to order from my dealer for this external re-seal. Still deliberating if I should just pry out the torque converter seal ring and drive a new one in VS taking the pump out of the trans....

I have successfully rebuilt a 722.6 before so I know how to work at transmissions and keep everything pristine clean.

 

[JC220]

OK just got to this today. Here are pics of my 75k miles trans BEFORE cleaning anything at all:




Both front and rear radial seals are bone dry. As is the left side of the transmission. The right side is leaking, most likely the Bowden cable has leaks.

Now steam cleaned prior to carrying out any work:



I am leaving both radial seals alone. I will renew the shift linkage seal ring since that would be difficult in the car. And a new Bowden cable + all seals on the right side. + New pan magnet, filter and rubber gasket.

 

[gsxr]

Joe, might as well do the left side too, seals are cheap and it will take very little time. Mostly the governor cover and vac modulator (in addition to the selector lever which you have in the current plan). The O/L switch can be skipped, this isn't difficult with the trans in the car, and IME the switch itself either fails or leaks through the electrical terminals.

I'd seriously consider both front & rear radial seals though - also easy and cheap, with minimal risk.

If the front pump O-ring is bone dry, you could gamble on leaving that one alone... that one is much more time consuming, and more difficult in general. Not fun if you don't have the special tools.

 

[JC220]

Joe, might as well do the left side too, seals are cheap and it will take very little time. Mostly the governor cover and vac modulator (in addition to the selector lever which you have in the current plan). The O/L switch can be skipped, this isn't difficult with the trans in the car, and IME the switch itself either fails or leaks through the electrical terminals.

I'd seriously consider both front & rear radial seals though - also easy and cheap, with minimal risk.

If the front pump O-ring is bone dry, you could gamble on leaving that one alone... that one is much more time consuming, and more difficult in general. Not fun if you don't have the special tools.

Yes Dave, I appreciate your advice and I will follow it and renew those other seals too. Besides the Pump O ring seal which is 100% bone dry. Since I do not have any of the special 722.3 tooling I am best to leave well enough alone there.

The Bowden cable cover has a kink and break in it. So I think I need to order a new Bowden cable itself + associated seals.

 

[JC220]

This is the list of seal rings for re-sealing my trans externally I just sent to my parts guy:

B1 Piston Seals:
A0059978648
B1 Boot – A1152721092
A0009970248
B2 Piston Seals:
A0059977048
A1402770455
A1262770955
Governor Seal left: A0169973948
Governor Seal right: A0169973248
Front Radial Seal: A0109974947
Rear Radial Seal: A0129978747
Bowden Cable Assembly: A1402700273

Bowden Seal Ring: A0169970448

Updated Vac Modulator: A1262709179
Vac Modulator Seal Ring: A0149971148
Selector Shaft Seal behind NSS: A0139970446
Rear Black Switch Seal Ring: A1153040160
Trans Dipstick O Ring: A0169972948

I am aware some of the seal rings may overlap with the new parts but just being sure. Some part numbers may also be superseded but he ill check and correct that as needed.

FWIW my 1995 C140 500 ccoups trans no is 722.370 04 127349

 

[JC220]

I also added 140 993 14 26 Diaphragm Spring per Klink's advice below:

B1 722.3 cover - seal change help please? | Transmission and Driveline

Cheers all! In the project car, 1995 SL500 B1 Seal is leaking, I manged to remove the assembly w/o dropping transmission, but for the life of me, this B1 cover, the white seal Needs to be re-installed, can't figure out how to take these pieces apart, I can see a clip there, I'm...

www.500eboard.co

Watch out for 722.3 Re-Seal pics coming in my owners thread over the holidays