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Topic: Hydraulic fan controller DIY (Read 5333 times) previous topic - next topic

Hydraulic fan controller DIY

So a month ago Sven spoke about the Hydraulic fan controller modification
Hydraulic fan controller
My controller has been at 100% since I picked it up in June. Drove 6k miles and really couldn't figure out exactly what I wanted to do. His post was enough to get the wheels in motion. I ordered three of the valves and associated bungs and fittings. I was holding off till I did my Aquahot to change fluid on everything at once. Aquahot is almost ready to reinstall once it's area is cleaned and sealed. I got the last of the wax valve components today and will be able to move forward with the install. I chose the 210 deg valves because it makes sense to me and we do not have air conditioning requirements for the Hydraulic fans. Greg, misterEd has been quite a wealth of knowledge and brought up some very good points about a IAT "inlet air temperature solenoid. More on that after installation as that is a secondary installation if needed. I understand that I could see up to a one mile per gallon increase by not having a up to 80 hp fan running at 100% more to come in following days.
Scott


Important update:

NOTE; Please read posts 36-40 for important changes made to this post

After testing, I do not recommend installing the thermostat in the lower hose post the transmission cooler.
Just runs too hot in that location.

Re: Hydraulic fan controller DIY

Reply #1
My new Thermal Valve was installed Friday.  Works fine.

The line to the hyd motor installed fine.  The return line had to have an adapter from my hyd shop installed to fit the coaches return line.

Then the fans started on high with the engine cold.  Quick call to Source Engineering determined they installed a restrictor on the line to the hyd motor to make the fans run on high for the SOB folks that have the dash A/C condenser radiator mounted in front of the engine radiator.  Removed the restrictor per their instructions and all is working fine.

Re: Hydraulic fan controller DIY

Reply #2
My new Thermal Valve was installed Friday.  Works fine.

The line to the hyd motor installed fine.  The return line had to have an adapter from my hyd shop installed to fit the coaches return line.

Then the fans started on high with the engine cold.  Quick call to Source Engineering determined they installed a restrictor on the line to the hyd motor to make the fans run on high for the SOB folks that have the dash A/C condenser radiator mounted in front of the engine radiator.  Removed the restrictor per their instructions and all is working fine.
Rudy, did they install on lower radiator line? Was thinking about this last night. Sven was installed there. This would allow to control radiator outlet temp. If it was placed after the transmission cooler it would also try to control the temperature including added BTUs from the retarder when in use. This would reduce the radiator saturated temperature during heavy retarder use. I have yet to experience "engine" water temps climb do to retarder use, however I have never used at near max GCWR and I plan to in the future In the Sierra Mountains. In writing this I see no downside too it being downstream of the transmission cooler before it enters the engine for cooling.
Scott

Re: Hydraulic fan controller DIY

Reply #3
So after thinking about were it should be mounted talked to several friends of mine and one that rebuilds large Allison transmissions. He was very knowledgeable about the retarder and recommended installing the wax controller past the retarder/transmission cooler. Personally he would prefer the trans to be operating a 100 deg cooler but likes the fact that if monitoring cooler output temps this would help reduce trans oil temps more when actually needed on long descents. Will also run radiator fans higher on descents to cool coolant and additionally increase dynamic braking do to the hydraulic  loads running the fans. 20/20 hindsight I would of ordered three weld in bungs to place in all three positions to vary and see what I liked the most. This will cause radiator temperature to be higher do to reduced fan load demand increasing economy. That said proof is in the results. Who knows till then.
Scott

Re: Hydraulic fan controller DIY

Reply #4
Just a reminder, anytime you are using the retarder for LONG descents it is important to use the Allison down arrow to keep the engine at the upper end of its RPM range and use the minimum retarder setting to keep your speed in check.

Higher engine RPM keeps the water pump turning faster so more coolant flow through the radiator and transmission cooler.

Re: Hydraulic fan controller DIY

Reply #5
Just a reminder, anytime you are using the retarder for LONG descents it is important to use the Allison down arrow to keep the engine at the upper end of its RPM range and use the minimum retarder setting to keep your speed in check.

Higher engine RPM keeps the water pump turning faster so more coolant flow through the radiator and transmission cooler.
Absolutely agree. And with sensing after cooler at the peak of added BTUs from the trans retarder will increase fans speed during low engine demands
Scott

Re: Hydraulic fan controller DIY

Reply #6
Good point. Thanks

Re: Hydraulic fan controller DIY

Reply #7
I like your idea of a 210 fan controller. I have a 190 fan controller and it is installed in the middle of the pipe from the thermostat
housing. I have a 190 degree thermostat so I think a higher fan control would be a good idea. As far as going down hill I put in a
Jake Brake in so I don't use the retarder that much. I need to shift down to have it work really good. I thinking of putting in a
second floor switch and having Allison to program the trans to shift down automatically when that peddle switch is applied.

Re: Hydraulic fan controller DIY

Reply #8
As far as going down hill I put in a
Jake Brake in so I don't use the retarder that much.
You should have the best setup. I'll keep an eye out for one. You are costing me money. Really liked your post on it.
Scott

Re: Hydraulic fan controller DIY

Reply #9
So finally after all the distractions I was able to take the coach out and do preliminary trial runs and leak checks. Ran for about a hour total. Rechecked all new hose clamps and checked for leaks. I had replaced the hose clamps on the trans cooler from standard breeze hose clamps to upgraded breeze constant tension clamps from caps supply
Constant Torque CT Aero-Seal Hose Clamps – CAP Hardware Supply
Runs at 190 deg now all the time. This increased temperature was what I was looking for. Transmission temperature and retarder also increased. Seems to run better. IAT today never exceeded 105 deg. At full power during long pull. I did notice that the retarder temperature goes up much faster than before around town. I'm sure this is a result of running warmer. I think I will be adding the IAT solenoid and utilize for the retarder to run cooling  fans at max during retarder use time. Will know more after several hundred more miles. Baker grade in August is the real test. Increased fuel economy should also be recorded. Total Kit cost was under $350 for parts needed. My wax valve was installed after the transmission oil cooler. I do believe this will be best for fuel economy but I'll have to manage retarder temps much closer than I did before. I'll update after some more miles when I have a actual number of fuel used.
Scott

Re: Hydraulic fan controller DIY

Reply #10
Forgot to mention the background fans speed is almost zero. I installed a needle valve to easily adjust up if needed but so far have not. At zero the fans do not run at all.
Scott

Re: Hydraulic fan controller DIY

Reply #11
Scott you need the fans to run to keep the after cooled air cool. I put a 190 degree thermostat so the engine runs at 190 and I might
do what you did and get a 210 wax valve.

Re: Hydraulic fan controller DIY

Reply #12
Forgot to mention the background fans speed is almost zero. I installed a needle valve to easily adjust up if needed but so far have not. At zero the fans do not run at all.
Scott

I would be VERY concerned about intake air temperature with no air moving across the CAC!

Re: Hydraulic fan controller DIY

Reply #13
So I too was concerned. Today I never saw above 110 deg. I still think that the IAT Solenoid is a good safe guard. Thinking summertime is the test. Once everything is hot fans are running to cool
Scott

Re: Hydraulic fan controller DIY

Reply #14
Screenshot

Re: Hydraulic fan controller DIY

Reply #15
Scott you need the fans to run to keep the after cooled air cool. I put a 190 degree thermostat so the engine runs at 190 and I might
do what you did and get a 210 wax valve.
My neighbor with a 2002 295 is going to install wax valve after thermostat housing in upper radiator tube. Will runs fans more I believe. Another forum member has also got a install kit and his install may also be different. Installing two solenoids sounds kinda redundant but would address all concerns. I'll look into the costs.
ALSO just noticed that the bedroom reflects the added heat. May add cooling fans sooner than I thought. It's a big heat sink. Lol.
Scott

Re: Hydraulic fan controller DIY

Reply #16
What was ambient temperature when the screen shot above showed 97 degrees F?

Re: Hydraulic fan controller DIY

Reply #17
About 70.

Re: Hydraulic fan controller DIY

Reply #18
Would of stopped and increased fan speed if it was higher. Will watch and collect more information as I go forward. Having a way to view fan speed would be nice while driving
Scott

Re: Hydraulic fan controller DIY

Reply #19
Would of stopped and increased fan speed if it was higher. Will watch and collect more information as I go forward. Having a way to view fan speed would be nice while driving
Scott
Is there a photo tachometer with a remote sensor?