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Topic: Sundstrand Thermostatic Hydraulic Valve seeps oil (Read 636 times) previous topic - next topic

Sundstrand Thermostatic Hydraulic Valve seeps oil

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?
John & Genni Kerbs
ex 1993 U280 40'
1997 U320 40"
Build #5171
Engine: M11 450
Floor plan: walk thru bath

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #1 –
How about a photo where the seep is? Swivel should be able to be replaced by a hydraulic shop.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #2 –
Might be worth it to call Sunstrand also.
 Richard B
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #3 –
Capping off the two hoses will force hydraulic fans into high speed. Connecting the two small hoses together keeps fans at low speed.

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #4 –
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.
John & Genni Kerbs
ex 1993 U280 40'
1997 U320 40"
Build #5171
Engine: M11 450
Floor plan: walk thru bath

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #5 –
Good job John!

  Richard B
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #6 –
Quote from: gkerbs56 –
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?

Any info on engine hours? 
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #7 –
Coach has 10,000 miles. I will get the hours later today.
John & Genni Kerbs
ex 1993 U280 40'
1997 U320 40"
Build #5171
Engine: M11 450
Floor plan: walk thru bath

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #8 –
Should have saved $7.00.
I have O'ring kit with dozens of O'rings
1993 U300, 6v92
build 4366
USAF retired, Flight Engineer, C124, C130
 ATP, A & E.  & ex AI

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #9 –
Can you offer more detail steps in removing valve, keeper wire and seal? Any photos of how valve looks when off engine or apart?
 

Re: Sundstrand Thermostatic Hydraulic Valve seeps oil

Reply #10 –
Quote from: gkerbs56 –
Coach has 10,000 miles. I will get the hours later today.

97 320 with 10,000 total miles?
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4