Repair within the hydraulic system on a ZTR

[Keith]

My 4-year-old Yazoo/Kees 61" ZTMax has been a pretty good, trouble free mower. But a couple weeks ago I noticed a rather large buidup of oily debris near the rear of the frame. Upon closer inspection it looked to be either leaking from the left side pump or the cooler, located between the two pumps and directly behind the fluid tank. I think I have determined it is coming from the cooler. Anyway, good thing it has a two gallon capacity :eek:

What precautions need to be taken when servicing the hydraulic system? I would like to do the repair myself, since it is pretty well torn apart in the shop right now. I have not opened the hydraulic system yet though. Is this pretty straight forward? Replace the cooler, refill, leave it up on jackstands and just operate it with no load until the air is all purged? Any advice, especially from those who have done similar repairs would be greatly appreciated.

Thanks,
Keith

[Keith]

Anybody?

[mmathys]

Hi Keith

I don't have any experience with a mower hydraulic system but I did work on Caterpillar hydraulic systems for over 10 years. The most important thing is to make sure there is no pressure in the system when you start to remove the lines. This is usually done by moving all the control levers through every position with the engine off. If you have electric controls then you would do this with the ignition switch on and the engine off. When you do remove the hoses make sure the oil is not hot and wear safety glassed and gloves. I don't know if you have any hydraulic cylinders or just a hydrostatic-type drive so this might not be an issue.

As for resealing the pump make sure everything is clean. Us the correct OEM gaskets and seals and do not use gasket cement unless the manufacture specifically recommends its use. It can add thickness to critical bearing and pump clearances.

If you have any specific questions I'll try to help.

Good luck

Mark