Repairs toro zmaster hydro-gear leak

[klein]

hi i have a toro

built in 2001 so it is 17 years old
mod = 74240
ser = 210000507
hydro-gear pump = bdp-10l-121p



one of the pumps is leaking on my toro zmaster , i need to replace the gasket circled in red in the picture. i believe if i loosen the mount for the oil filter
and move it out of the way. i can pull the pumps back housing and replace the gasket without breaking loose any of the hoses. my question is how do i prime the pump , and has anyone tried this without pulling the hole pump ?

 

[bertsmobile1]

Hydro drives are made in clean room enviroments.
If you split it on the mower you will be replacing a lot more than the gasket in the future,
It has to come off then get cleaned spotless before the cases are split.
I degrease followed by a soda blast followed by a hot water rinse.
The workshop bathroom then gets sprayed down to get rid of dust there and after that I get stuck into hydros.
If one has to be left it gets covered with a damp shop cloth.

Hydro Gear manuals are on line and they are very helpful if you email them.

 

[klein]

according to BDP-10L (PL)
Hydrostatic Pump
Service and Repair Manual
it stats

i do know what you mean. and i do understand the risk . is there a best way to purge the pump of air ?

 

[BlazNT]

Purging Air from Hydraulics
1. Raise rear wheels off ground. Brace with jack stands.
2. Put bypass valves so it freewheels.
3. Get on mower start it and release the brake.
4. Push drive lever full forward for 10 seconds the full reverse for 10 sec. Do this 10 times for forward and 10 times for reverse alternating between each.
5. Return levers to the parked position and set brake. Turn off the mower. Move bypass valve bake to normal operation.
6. Get back on the mower and start it. Do step #4 again.
7. Return levers to the parked position and set brake. Turn off the mower.
8. Return mower to ground.
9. Test for proper working. If not repeat.
10. Check oil level and fill.

 

[klein]

sorry it has been a while
tractor is running again !
replacing the gasket with the pump in the zero turn is possible.
but in the long run i took the pump off .
with it in the tractor i put the charge pump on backwards = no pump fluid
i took the hole pump out and went through it on the bench, i put the charge pump on backwards again = no pump fluid
i took the hole pump out again and went through it on the bench, reread the pump pdf, searched google and found one post that
talked about the charge pump, cw and ccw that it matters how it goes back on.
my charge pump cover has a square punch mark by one of the bolts, check the other pump and installed charge pump cover the same way = yes pump fluid
thanks guys