722.3 Transmission 2nd pump reseal question - PeachParts Mercedes-Benz Forum

ps2cho · #1 10-25-2011, 10:18 PM

I thought my leak was at the (then found) cracked kickdown switch, but guess not.

I got under today and the same place is wet....so I looked up. Fresh fluid. Seems like the (aux/secondary pump) is leaking? Is that the correct part above?

Can it be resealed just by dropping the transmission mount? Anyone know?

How difficult is the rear pump compared to the front? Since the front was a royal PIA (just the actual pump seal, not the tranny removal)

rs899 · #2 10-26-2011, 09:17 AM

Yes, that's it. It's not hard to do, but I have only done it on a bench. If you can get to it, I don't see why you couldn't do it on the car.

ps2cho · #3 10-26-2011, 11:52 AM

If I am only there to reseal it, is it just the O ring (22) in the photo above or is there more?
It mentions in that manual further on to remove the switch-off piston and check the o-ring inside. Is this necessary?

Stretch · #4 10-26-2011, 02:33 PM

There a nice parts diagram here that might help with what goes where...

http://www.ganzeboom.net/images1/ganzeboom/parts/Mercedes/722.3,%20722.4.pdf

ps2cho · #5 10-27-2011, 12:25 AM

It actually doesn't look bad at all now.

Looks like its the following seals:

I'm gonna give it a shot.

Since I am going to be doing it with the transmission still in, anything I should know specifically due to the lack of space?

bunksbbq · #6 10-28-2011, 02:43 AM

These are the steps I followed when working on my govenor on the other side. two biggest cautions are to watch out for the head hitting the firewall when you lower the transmission and making sure you reassemble the flex disk assembly correctly. You should have plently of room to pull out the pump itself, its not that big.

1.Remove fan shroud.

2.Support transmission with jack and block of wood under pan

3.Remove transmission mount

4.Disconnect exhaust mount

5.Mark for reassembly, and remove flex disk.

6.Once done, release jack and transmission will drop a few inches

Good luck.

ps2cho · #7 11-11-2011, 09:51 PM

Got it without removing the flex disk and disconnecting exhaust. Just need a good angled tool.

I hope that spring does what I think it does -- allows the pump to align itself into the output shaft because I put it back in unaligned because it was just impossible to do it. I believe that is what it is for -- there is no other reason there should be a spring there.

Also, I wonder if the pump only works in final drive? I can't seem to find out "how" or "when" it works.

big dog 2 · #8 01-26-2012, 12:51 AM

I thought the picture of the pump leaking was from my transmission! Mine is leaking in that location too! How in the heck you got that out while still in the car is beyond me!

So I have an incontinent transmission (front pump seal and now this rear/aux pump) that shifts fine but just leaks. Guess I will just live with it for now.

ps2cho · #9 01-26-2012, 01:43 PM

Just make sure its not your kickdown switch, they tend to get hairline cracks and leak.

I got mine out by dropping the transmission mount and letting it come down a little. Its tight, but doable.

Just make sure if you do it, don't make the mistake I did and not lock the axial support back in place.

BENZ TEK · #10 01-26-2012, 05:24 PM

I usually remove the gears from mine. They are only there for push start purposes anyway!! lol Just make sure that the govenor is locked in place before tightining the 10mm nut.

jdere31760 · #11 03-23-2019, 10:18 PM

Quote:

Originally Posted by ps2cho

Got it without removing the flex disk and disconnecting exhaust. Just need a good angled tool.

I hope that spring does what I think it does -- allows the pump to align itself into the output shaft because I put it back in unaligned because it was just impossible to do it. I believe that is what it is for -- there is no other reason there should be a spring there.

Also, I wonder if the pump only works in final drive? I can't seem to find out "how" or "when" it works.

I tried dropping transmission without removing flex disk but could not get transmission low enough to remove secondary pump.

jdere31760 · #12 05-15-2020, 05:23 PM

Quote:

Originally Posted by jdere31760

I tried dropping transmission without removing flex disk but could not get transmission low enough to remove secondary pump.

Did anyone successful remove the secondary pump recently?
If yes, exactly what tool did you use? I can't get my hand inside the space since the transmission won't drop enough. Thanks!