There are different kinds of hydrostatic motors, (for this blog) if you have a motor that has a block it may have a integral shuttle and low pressure relief valves.

Place the motor down on its mounting flange and untighten the relief valves and plugs that are in the block. Take out the four bolts that keeps the valve block in the motor, then take it out. Next take out the o rings and all other rings that are on the mounting flank of the valve block.

Take off the lower relief valve cartridge. This type does not have back up rings, only one o-ring. Then take off the high pressure relief valve from the block. It has two white back up rings and one o-ring in the lower part of the groove.

Both the low and high relief pressures come from the factory already with a default setting. If you were to look on the cartridge it will tell you the settings.

Make sure to seal all open ports. Clean the outer part of motor before you put it together. Replace all gaskets and seals. Use some kind of lubricant when putting the gaskets, seals and orings back into the unit. And make sure to put new parts in if any are damaged.

If you have further questions about installing parts or if you need to have your unit repaired, call us at

800-361-0068

sales@htsrepair.com