Has any one have a parts breakkdown on a 9w4842? All I have is on a 7w1 and up book.. It looks like the seal and retainer are basically the same on these . I show a shaft seal 5f4721. I have never had the whole unit off,
but it looks like the 44 shaft slides out of the crank coupling, then the seal
is held in by the four bolt hole retainer. It is not clear what seals the retainer.
Maybe the o-ring seal 5f3144? I'd like to get everything at once for this reseal job.
Are there any mechanical tricks for the shaft and coupling dissconnect?

The procedure and parts for the 9W are the same as the 7W. There are a couple of different style couplings but they use the same seals.
Yes, the pump unit just slides off the splined shaft. There may or may not be provision for jacking bolts to separate the gear flange from the crankshaft flange.
Takes two # 4F9174 "O" rings
One # 4F9172 seal
One # 4F4946 coupling seal "O" ring

Thanks OM for the info. I lost 2.5 gallons in 6 weeks and about 5 hours
run time. The unit always had a little seepage but this time it came out in a steady drip. About 2 months ago I greased the coupling. I wonder if I blew
the seals out with too much grease or if its just a coincedence ?

If your losing that kind of hydraulic oil you may have to go further in and replace pump shaft seals. The parts I listed are just for the coupling and primarily to hold in the grease and keep out the dirt. There are also a couple of magnetic drain plugs with "O" ring seals and the filter cover plate that can leak. Be sure they are not contributing before going in:D Also the control shaft seals can go out and cause quite a mess.

The shaft seal is a #5F4721. The seal retainer can be removed without disturbing the pump cover.

I've wondered if the new "Bar's Leaks" sealing additive for leaking rear main bearing seals could possibly act a a temporary fix for slow leaking low pressure seals in hydraulic pumps, transmissions and final drives.

The "Bar's Leaks" additive for leaky radiators has certainly worked great for me.

Any opinions?

Fred (tinytec)