Hydraulic Cooling Fan

[moisheh]

Our 08 Dynasty has a HD hydraulic cooling fan. When we first bought the unit I could not hear the fan running. Most of the hydraulic systems use some sort of by pass valve that allows most of the fluid to just return to the tank until a temp. sensor calls for more cooling. After all the climbing we did in Oregon I noticed that I can hear the fan all the time. Even on a cool morning after start up. This cannot be normal. Any suggestions on what to look for? My first thought would be a bad temp. sensor. If I can find it I could check it with an ohmeter.

Thanks

[moisheh]

Our 08 Dynasty has a HD hydraulic cooling fan. When we first bought the unit I could not hear the fan running. Most of the hydraulic systems use some sort of by pass valve that allows most of the fluid to just return to the tank until a temp. sensor calls for more cooling. After all the climbing we did in Oregon I noticed that I can hear the fan all the time. Even on a cool morning after start up. This cannot be normal. Any suggestions on what to look for? My first thought would be a bad temp. sensor. If I can find it I could check it with an ohmeter.

Thanks

[Happycarz]

There is a good description of the hydrauic fan operation in my 08 Camelot owner's manual. The same was in my 99 Dynasty manual. Hopefully, your manual has it also.

[Camelot Camper]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by moisheh:
Our 08 Dynasty has a HD hydraulic cooling fan. Any suggestions on what to look for? </div></BLOCKQUOTE>
While you're there, make sure the high pressure hose from the transmission PTO is not rubbing on the case. One of the Monaco International members at the balloon rally last week showed me his hose that started to leak due to rubbing on the case edge. He lost 3 gallons but noticed the leak at a rest stop walk around that he always does.
CC

[moisheh]

I found the problem today. I am recovering from major surgery and could not crawl under the unit until this morning. Looking at the fan motor I could see one hydraulic line and a starnge stud sticking out of the hydraulic motor. I wondered how could the fan motor change speeds if there was no means of controlling the hydraulic flow. Further investi gation revealed that this stud is part of the hydraulic solenoid that does control the flow. The mating piece was hanging from a wire bundle. Apparently when they assembled the drive train this solenoid was either missing a nut and washer or it was loose. Of course it is some wierd very fine metric thread ( Italian parts). I will call tech support and hope they can send me the parts. I did install the dangling piece and the fan slowed down right away!!!!!

[knebrdr]

I do not want to hijack a thread but the Cummins website has an interesting series of articles on fuel mileage. One segment is on fan operation/mileage.
Randy