My 97 U320 with M11 has a Sundstrand Thermostatic Hydraulic Valve located at rear of engine screwed into the large metal coolant tube (approx 3 inch) that seeps hydraulic fluid when engine is running. This valve has a swivel where the 2 small hydraulic lines are attached. The oil seeps out of the swivel. This valve is available from FOT for $ 611. Has anyone tried to remove the swivel portion of the valve and replace the seals inside?
How about a photo where the seep is? Swivel should be able to be replaced by a hydraulic shop.
Pierce
Might be worth it to call Sunstrand also.
Richard B
Capping off the two hoses will force hydraulic fans into high speed. Connecting the two small hoses together keeps fans at low speed.
I spoke with Sundstrand and a local hydraulic shop. Both suggested replacing internal seal. The swivel is held in place with a keeper wire. When this is removed the swivel comes out. Only 1 o-ring inside. I cleaned and inspected the internal surfaces and replaced the o-ring. I then ran the engine for 45 min with no leak. FOT wants $611 for this valve. I spent $7.00 on o-rings and fittings to attach lines to each other if a leak develops on the road.
Good job John!
Richard B
Any info on engine hours?
Coach has 10,000 miles. I will get the hours later today.
Should have saved $7.00.
I have O'ring kit with dozens of O'rings
Can you offer more detail steps in removing valve, keeper wire and seal? Any photos of how valve looks when off engine or apart?
97 320 with 10,000 total miles?