Hydraulic Fan Leak

[Gary and Judy]

Second try:
When I checked the hydraulic power steering/hydraulic fan level I was down half a quart. I checked around under the coach and found a leak in the hydraulic cooling fan.

Has anyone had experience with a similar leak.

I always check levels each day before I start the engine, so I know the loss was all in one day.

Gary

[Gary and Judy]

Second try:
When I checked the hydraulic power steering/hydraulic fan level I was down half a quart. I checked around under the coach and found a leak in the hydraulic cooling fan.

Has anyone had experience with a similar leak.

I always check levels each day before I start the engine, so I know the loss was all in one day.

Gary

[Dave Fernandez]

Hello Gary & Judy:

One of our Alpine So Cal members had a bad hose going to the fan motor which would caused a sever leak which was in a fitting. Once the hose and fittings were replaced the leak stopped. Clean the engine and fan first than you can use an ultra violet leak detector and place it in the reservoir. You can run the engine and see if you can detect the leak if not, you will have to drive it for a short distance than you can look for the leak using a black light.

For the hose we went to the Hose Man (So Cal area) and they manufactured a new hose in about an hour. They used the old hose as template.

I hope this helps.

[EngineerMike]

G- The hoses are a high pressure type @ >1000psi, but the fittings tighten w/standard wrenches. If you have wrences that big, check for proper seating of the ends (presumes there is not an obvious leak in the "rubber" part of the hose). They should be well seated.

[Gary and Judy]

I have now wiped the area of the fan down thoroughly and just driven another 30 miles. A total distance since the reservoir was last checked full of 280 miles. I needed a full quart of Dextrn III to fill to the line.

A visual check confirms that there is a drip coming from the fan motor body. I will see if I can tighten the hoses.

A call to Cummins confirmes that this is not part of the engine train. I am going to see what WRV has to say.

Gary Dinsmore

[Pollo man]

Gary, we just discovered our fan is leaking. Cleaned it up and appears oil is coming out the fan shaft seal.
WRV help out with part name/numbers?
Just reading on RV NET about this problem and possible fixes. Might check it out.

[Gary and Judy]

Here is the final fix for our Alpine.

First what appeared to be a seal leak was actually leaking from a missing cap screw in the face of the motor. This is up under the fan hub. A cap screw had dropped out, and a second one was loose. The O-ring was cut by the high pressure hydraulic oil. Since it was coming out by the shaft it looked like a seal leak.

Second. The motor for the 2001 Alpine coach is no longer manufactured. I called Sauer-Danfoss (US) Company and their representitive assured me the replacement pump was an exact fit.
Their number for the old pump was:
p/n 551101101101210
Their number for the supposed replacement was:
p/n 551101292210
I purchased the replacement pump - 60 days to ship and deliver. Contracted a local mechanic shop to change the motor out. It did not fit.

Third: we scrambled and found a replacement O-ring and rebuilt the old motor.

So far it is working.

Gary Dinsmore 503-803-6698