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Topic: Granvilla cooling fans (Read 608 times) previous topic - next topic

Granvilla cooling fans

Anyone know how to make the radiator cooling fans run on high speed continuously. 1993 with a 8.3 Cummins
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Granvilla cooling fans

Reply #1 –
Bruce,

Not your coach, I take it.

Our 1993 U280 has the typical dedicated belt driven hydraulic pump that powers the two cooling fans.  Our coach does not have any kind of 2-speed fan controller in the hydraulic hose system feeding the fans.  On our coach, the fan speed simply increases as the engine speed increases.  There would be no way to "make the cooling fans run on high speed continuously" other than having the engine running at high speed continuously.

I'm specific about how our coach works, because I've seen some random posts on the Forum by owners of other '93 models that suggest they DO have a 2-speed fan controller of some type.  As is typical with Foretravel, you can't depend on similar year model coaches having the exact same system components.

Good luck with your question!
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Granvilla cooling fans

Reply #2 –
Ours has the Hi / Low speed valve. Controlled by a NC contact on a temp switch on the engine block. When temp reaches 190* the contact opens, drops out the valve and it switches to high speed. Using this method if the contacts fail "open" the fans default to high speed cooling.

Now that this subject has come up, I'll need to research the "specifics" of how this is actually accomplished, by a two speed pump or just a flow diverter between the pump and motors.

Hopefully there will be a hydraulic print showing this in my "Big Red Book" 🤔
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Granvilla cooling fans

Reply #3 –
I believe our 93 also had a dash switch to make them run high speed.....
Pretty sure anyway it had a DD6V92
Frank & Connie Williams
1999 U320 '36
Build: 5466
MC: 18335

Re: Granvilla cooling fans

Reply #4 –
On some of those if there is a wire harness going to a valve in the hydraulic line, you can unplug the wires and it should go to high speed.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins