[kc5gxc]

Hello and thanks for letting me check in.
I have a used ExMark Lazer Z HP....don't know the year. 48" cut commercial deck.
I have a hydraulic leak on the left pump. Think it's leaking out of the side of the "dump valve".
Nothing in my book about this.
Anyone know if I can remove the dump valve and replace O rings to stop this leak ? I tightened up the main nut on the valve and it really slowed down a lot, but still weeping some.
Thanks, Pete

 

[Brad]

I am not familiar with the hydraulics end of the Lawn Mower repairs so I will let a more knowledgeable member help you out here. Just wanted to welcome to you our forum.

Good Luck!

 

[Mark777]

Hi, Pete

If the tightening of that nut slowed down the leak, I'm sure you're on the right track for a permanent repair. It is highly likely "O" rings (or fiber/Teflon packing washers) is the culprit.

Like Brad though, I'm not real familiar with your brand specific hydraulics, and my opinion is from experiences with hydraulics in general.

 

[kc5gxc]

Thank you gents

Thanks for the welcome and the advice.
Pete

 

[Mark / Ohio]

Do you have an exact model number available?

Maybe using it we can either dig up a service manual on the net or determine the manufacture of the pump and find a breakdown of it on the pump manufactures website.

 

[kc5gxc]

Thanks, Mark

Hi Mark
The model number is LHP4821KA.......Serial # is: 264202.
The hydro pump is part #: 1-603841....from what I have found, this pump has been superceded to Toro PN#: 1032766....for sure I have the old old one.
I have the operators' manual and the parts manual.
All I see is a name for the part leaking as "dump" valve.
I tightened up on it's main nut, and the leaking has nearly stopped.
Am unsure what will happen if I pull it out and check for bad 0 ring, etc...
Looks like I have about got it whipped simply by tightening the nut.
If it is a simple pull out and replace 0 ring, though, I will sure do it or apply teflon tape or whatever it needs.
Machine works good....a little jerky on the control on the side that doesn't leak !!! ha.
Appreciate the help.
Pete

 

[Mark / Ohio]

Is the dump valve also what you loosen to get the motors to "free wheel" so you can push the mower without the engine running? Or do you have a separate bypass valve for that function?

Reason I ask is I'm not finding exactly what I'm picturing from your description of it. But here is what I found and maybe you'll find in one of the manuals what your looking for.

The Exmark model 1-603841 looks likely to cross to a Hydro-Gear model BDP-10L-121P orPL-BGVQ-DY1X-XXXX Using page 23 of this cross reference:

http://www.outdoordistributors.com/pdf/HYDRO-GEAR/2007_Reference_List_(working)_10-18-06.pdf

None of the manuals on Hydro Gears site

Hydro-Gear Service Repair Manuals

seemed to match up so I found another website:

Hydro-Gear Parts online catalog,

Which is where I found the cross reference which seems to backup the comparable model numbers listed on several online retail websites. You might want to dig through this P and BDP series service manual and see if any of them match up to what you see on yours.

http://www.outdoordistributors.com/pdf/HYDRO-GEAR/P_series_and_BDP_pump_SM.pdf

Also see if this BDP 10L diagram looks anything like the one you have:

http://www.outdoordistributors.com/pdf/HYDRO-GEAR/BDP-10L.pdf

If none of these match up maybe the original Hydro gear number is stamped on the pump someplace and will show up in one of the websites listed above.

 

[kc5gxc]

Hi Mark
Reading the manual some more, found that the dump valve is the "drive wheel release valve". Great when they switch terms on you !
You are correct. The last schematic you sent has the same thing and a kit for it also.
Think I will pull this one out and see what it looks like. Bet there's an o ring or something bad. Will probably do it soon, and I will report back here with results....gonna be rainy tomorrow here.
Thanks again, Pete