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Topic: Hydraulic fan controller DIY (Read 3867 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.
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

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.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Hydraulic fan controller DIY

Reply #2 –
Quote from: Rudy –
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
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

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
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

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.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Hydraulic fan controller DIY

Reply #5 –
Quote from: wolfe10 –
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
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

Re: Hydraulic fan controller DIY

Reply #6 –
Good point. Thanks
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

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.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Hydraulic fan controller DIY

Reply #8 –
Quote from: oldguy –
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
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

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
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

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
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

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.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Hydraulic fan controller DIY

Reply #12 –
Quote from: dsd –
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!
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

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
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

Re: Hydraulic fan controller DIY

Reply #14 –
Screenshot
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

Re: Hydraulic fan controller DIY

Reply #15 –
Quote from: oldguy –
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
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

Re: Hydraulic fan controller DIY

Reply #16 –
What was ambient temperature when the screen shot above showed 97 degrees F?
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Hydraulic fan controller DIY

Reply #17 –
About 70.
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

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
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

Re: Hydraulic fan controller DIY

Reply #19 –
Quote from: dsd –
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?
Matt B
1998 u-320

Re: Hydraulic fan controller DIY

Reply #20 –
I'm sure there is. I'll be looking into something
Scott
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

Re: Hydraulic fan controller DIY

Reply #21 –
Quote from: wolfe10 –
What was ambient temperature when the screen shot above showed 97 degrees F?

With 70 degree ambient temperature and driving 75 MPH and only seeing 97 degree intake temperature (assuming that is an accurate number) there HAS to be air flow through the CAC.

But, as you said, summer temperatures will be the biggest test.

Like your idea of fans to high anytime the retarder is on.  Additional braking AND additional cooling.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Hydraulic fan controller DIY

Reply #22 –
IAT solenoid would be probably in the 20-30% fans speed speculating And 100% for retarder. Currently background speed is just tuning the fans like 1%. I'm curious how much airflow is being caused by drawing air thru caused by low pressure area behind coach. Any way to get any airflow thru is beneficial. I know of no way to tell? Maybe a manometer measuring pressure differential? I'm still not fully comfortable yet with the setup but hopeful it will work. I still won't fully know till it's hotter. Also having a manual control of the 100% retarder selection might be beneficial to help manually overcool prior to shutdown for the trip to drop radiator temps and engine compartment temps. Hadn't thought of that till this post. Brett your keeping me thinking. Thanks.
Scott
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

Re: Hydraulic fan controller DIY

Reply #23 –
It is very unlikely there will be a condition where the fans will not be spinning when you actually need the charge air cooler to cool incoming air.

Specifically: when the turbo is making boost and the charge air needs to be cooled, the engine will be under load. When the engine is under load, it makes heat.  When it makes heat, the coolant gets hot. When coolant gets hot, the "wax valve" senses it and runs the fans.
1998 U270 34'

Re: Hydraulic fan controller DIY

Reply #24 –
Quote from: dsd –
. I'm curious how much airflow is being caused by drawing air thru caused by low pressure area behind coach. Any way to get any airflow thru is beneficial. I know of no way to tell? Maybe a manometer measuring pressure differential?

When you get that remote sensing photo tach, maybe set it up to read a fan like a pinwheel mounted right inside the engine compartment louvers on the rear.  That ought to give you some idea, and if you use a fan with known pitch should be able to calculate airflow volume.  Or, more simply, use a dc fan, let airflow motor it and measure voltage.

It's an interesting question with large implications regarding cooling efficiency.

"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS