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Topic: Fan Wax Valve Bypass (Read 408 times) previous topic - next topic

Fan Wax Valve Bypass

Was wondering if anyone had the information to test the Fan Wax Valve.  I'm feeling that mine fans may not be kicking in to high speed when needed.
I believe there was an electronic way to make the fans go into high speed or a way to bypass the hydraulic line to get the fans into high speed.

Also, any help pointing me to the location of the valve. I did replace my fan seals a few years ago, but don't remember seeing the valve. (Of course, I am old and senile) :(
Any help would be appreciated.
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: Fan Wax Valve Bypass

Reply #1 –
Hydraulic fan controller DIY
Lots of good info. I did install a needle valve so as to be able to set the background fan speed. Not the correct way to do it but easy and quick. Also I can effortlessly check that the fans are ramping up when the oil line is restricted I also added a shut off solenoid to ramp the fans to hi if I desire and also during retarder use and any time I'm braking. Really like to use it for super cooldown prior to parking to dump all the extra BTUs before we stop for the day. Makes a huge difference sleeping in the bed. Or cooking in the bed trying to sleep.

Re: Fan Wax Valve Bypass

Reply #2 –
Quote from: MarkC –
Was wondering if anyone had the information to test the Fan Wax Valve.  I'm feeling that mine fans may not be kicking in to high speed when needed.
I believe there was an electronic way to make the fans go into high speed or a way to bypass the hydraulic line to get the fans into high speed.

Also, any help pointing me to the location of the valve. I did replace my fan seals a few years ago, but don't remember seeing the valve. (Of course, I am old and senile) :(
Any help would be appreciated.
So I would guess that your coach does not have the wax valve. On the rear structure on the passenger side there will be a 2x4x6 inch box . Two oil lines going to it.  If you disconnect the electric plug it will close the valve and the cooling fans should ramp up to max. Hi failure item. Mine was failed from day one. Also they fail to full fan speed. ECM controls input for temps from engine, transmission, and IAT. Inlet air tempiture to the engine past the inter cooler. On a cold frozen engine and transmission it is possible to overtime the intake. Fans background speed should prevent and it will ramp up fans if it gets hi. Wax  valve is strictly looking at coolant temp after the radiator

Re: Fan Wax Valve Bypass

Reply #3 –
Quote from: MarkC –
.(Of course, I am old and senile) :(
Any help would be appreciated.
Welcome to the club!

Tim
Tim Dianics
Pam Sapienza
Vader PupZilla Labrador Canine Beast (AKA Pup)
Columbia, MO
1996 U320 4000
2021 Jeep Gladiator, Diesel

Re: Fan Wax Valve Bypass

Reply #4 –
My electronic controller failed on my last trip. VMSpc showed an increasing engine temp so I pulled over and unplugged the controller and the fans went to high and temp came down.. a month later Keith Risch installed a wax controller, temps looked go on the way home from nac, next trip is in a month.


Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Fan Wax Valve Bypass

Reply #5 –
I used a new rocker switch and spare wire to control my fan speed. 

Pat
Pat/Blue Angel
1995 U240 36ft
MC# 16511
Build# 4653