Go Back   iRV2 Forums > MOTORHOME FORUMS > MH-General Discussions & Problems
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 02-27-2009, 08:56 AM   #1
Junior Member
 
Join Date: Feb 2009
Location: Northern Minnesota
Posts: 21
Hi ALL, I'm new to this forum, and have asked around on other forums, but the problem won't go away. I live in northern minnesota (against my better judgement)and I happily get to use my 1999 Country Coach Allure, 330 Cummins 6sp Allison a few months out of the year for now anyway. Now the Problem; this rig has a side radiator with a hydraulic fan for cooling. The fan runs at full speed all the time, even when I first start up. The thing is very aggrivating and embarrassing, not to mention noisy and dusty, especially when I'm trying to leave a campground early. (Sorry to those early walkers on the curb side). I have contacted: Country Coach tech line and was told that the system is a "fail on" which means that if anything goes wrong in the hydraulic control (thermovalve, no electric sensors)for the fan,the fan will run at full speed, allowing you to continue driving without overheating. OK, the tech told me that if the thermovalve is bypassed, the fan SHOULD idle. I did the bypass (I do my own work so I don't pay a shop to "learn" how to fix something)and the fan Never changed speeds. According to the operator's manual, the fan SHOULD idle when the engine temp is under 190 degrees THEN should start running faster and reach full speed at about 220. The engine NEVER gets above about 185 because of the fan blasting. I changed all 3 canister type filters and all the hydraulic fluid (dextron III)the lines are in good shape with no deformities. Sauer-Danfoss is the manufacturer of the pump, fan motor, switching valve and thermovalve, they (their tech line) don't have any idea and I'm STUCK, I don't know what to do next. ANY IDEAS???? THANK YOU, sorry this got a little long.
__________________

__________________
Stakealot is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 02-27-2009, 12:27 PM   #2
Community Moderator
 
"007"'s Avatar


 
Nor'easters Club
Workhorse Chassis Owner
iRV2 No Limits Club
Join Date: Oct 2004
Posts: 26,804
Welcome Stakealot to irv2.
Here's a LINK that may help you or you can drop down in the forums to CUMMINS ENGINE FORUM and get some answers to your question.
In any case enjoy the forums and do post often.
__________________

__________________
98KSCA, 99MACA, 03 KSCA-3740- 8.1 Chev-- ALLISON Trans, now in good hands
VISIT the NEWMAR QUICK TIPS & EASYMODS 1 & 2
QUICK TIPS # 3
RV SYSTEMS & APPLIANCES & RECALLS --- TECH INFORMATION
"007" is offline   Reply With Quote
Old 02-28-2009, 02:12 AM   #3
Community Moderator
 
RV Wizard's Avatar


 
Country Coach Owners Club
Appalachian Campers
Gulf Streamers Club
Join Date: Mar 2000
Location: Chattanooga, Tn.
Posts: 12,062
Stakealot, welcome to iRV2.com. We are glad to have you join us here and we look forward to reading of your adventures and experiences. Sorry to hear of the fan problem. I do have one question as I have a very similar set up but on a Spartan chassis. My fan is driven by an anti wear hydraulic fluid; AW-45 to be exact. I know that originally there was a paper tag on the reservoir to only use this type of fluid but has long ago deteriorated, faded, and is invisible.
Are you sure your fan should have the Dextron III as a driving fluid? I recommend you check in this direction, as the Dextron III may not have the same viscosity and might cause your problem even in a by pass mode. Good luck and keep us posted.
__________________
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7
RV Wizard is offline   Reply With Quote
Old 02-28-2009, 05:32 AM   #4
Senior Member
 
Join Date: Apr 2003
Location: Oakton, Va
Posts: 1,149
I agree completely with doing the troubleshooting and as much of the work yourself as possible. I don't have a side radiator but have done some investigation. I believe that the engine temperature comes from the ECM. If your gauge still shows correct reading then it should be ok. Make sure wires are still connected. If ok go the next component. I can't help further but just narrow it down. Bet on some $100-$200 component to replace or maybe even just re-connecting a wire.
__________________
Jim Walker
N Virginia
2014 Palazzo 33.2
Cummins 6.7 ISB, Allison 2100 6 Speed
J Walker is offline   Reply With Quote
Old 02-28-2009, 08:05 AM   #5
Senior Member
 
Join Date: Apr 2000
Location: Crossville,TN USA
Posts: 437
Stakealot, FWIW, I have a 370 hp Cummins ISL on a Spartan with a side radiator. Unlike you I don't do my own maintenance and have learned to depend on Coach Care facilities . These are 40-45 Cummins shops that have dedicated bays, techs. and waiting rooms for we RVers.While getting an oil and filter change in Harrisburg, PA, the tech. mentioned that my fan was running excessively and that he was going to check it out on the computer. Come to find out, somewhere, somehow the fan settings got reversed, which caused it to run darn near all the time. He went in and reset the parameters and It has run like a charm ever since and that was almost 3 years ago. He also pointed out that with the fan operating with reverse settings that I was burning a lot more fuel. Almost immediately after he made the change my MPG went from low 6s to mid 6s and has held there ever since. Like I said FWIW, Ken,'04 DSDP....
__________________
Ken Roberts is offline   Reply With Quote
Old 02-28-2009, 02:50 PM   #6
Cat
Senior Member
 
Join Date: Jan 2005
Posts: 534
Most thermovalves bypass oil back to the hyd tank when the fan speed is not needed ( the engine is cool)if you do bypass the thermo valve you will overheat your engine. That is why it fails on or at full fan speed.If there is no electric control,and because the fan is at high speed, this indicates the fan pump is ok, this also indicates the fan motor is ok. If the only other thing that controls fan speed is the thermovalve. It must be a thermovalve failure.
__________________
Cat is offline   Reply With Quote
Old 03-01-2009, 10:41 AM   #7
Junior Member
 
Join Date: Feb 2009
Location: Northern Minnesota
Posts: 21
Thank You ALL for the welcome and the help and information. I really appreciate the ideas! The owners manual says to use Dextron III, the tag on the reservoir, although just about unreadable says Dextron II, which I think is the same thing. I also tried Blocking the line (temporarily)that runs to and from the thermovalve and again there was no change in fan speed. I was hoping originally that there was some sort of electronic control, but the CC tech line says there is no other control except for the thermovalve that controls the switching valve that is attached to the fan motor. According to Sauer Danfoss, the fan motor can use up to 47 horsepower at full speed. That can't be to good on the fuel milage, (now about 7)so I really need to get it fixed. I thought about a Coach Care facility there is one in north St. Paul, about 250 miles south. Does anyone have any experience with this shop? I think with the fuel milage boost and peace of mind and sanity, it will probably pay for itself eventually if I had a shop take a look. Thank You again.
__________________
Stakealot is offline   Reply With Quote
Old 03-02-2009, 04:27 AM   #8
Senior Member
 
Join Date: Apr 2003
Location: Oakton, Va
Posts: 1,149
Quote:
Originally posted by Stakealot:
I also tried Blocking the line (temporarily)that runs to and from the thermovalve and again there was no change in fan speed.
There must be something more to be learned. If you clamped the hose to the thermovalve and the fan still worked then there is some more plumbing and controls involved. Can CC take what you have learned so far and answer some more questions? There should be a control somewhere that is proportional to the engine temp. If the thermo valve has no electronic control that can provide proportional control then there may be another component that does that. If the fan is only full on or full off it is not a good design. Did it operate at reduced speed in the past? I would try to find out as much as possible before having a shop get involved.
__________________
Jim Walker
N Virginia
2014 Palazzo 33.2
Cummins 6.7 ISB, Allison 2100 6 Speed
J Walker is offline   Reply With Quote
Old 03-03-2009, 06:36 PM   #9
Junior Member
 
Join Date: Feb 2009
Location: Northern Minnesota
Posts: 21
Thanks for the input J Walker, The fan has Never run any differently as long as I have owned the rig, about 28000mi and 4 years. It runs at full speed from the time it is first started, until it is shut down. The thermovalve is a control for the switching valve that is "pilot" controlled. To me that means a small amount of fluid is allowed to pass through a bigger valve that is held open by pressure from the pump as long as the pressure is equal on both sides of the big valve. When the thermovalve starts to close, because the temperature in the radiator goes above 190 degrees, it restricts the return of the small amount of fluid, and the restriction causes more pressure to build up on one side of the big valve, causing it to begin to close. As the big valve (in the switching valve) closes, it directs more of the main flow of fluid to the fan motor (instead of bypassing back to the reservoir) causing the fan to increase in speed. Whew! that is about ALL I know about the controls of the fan. CC has helped me to get this understanding, but doesn't know what the problem actually is. They suggest I "try" a thermovalve,which is around $700.00 for the part. I would gladly do this if I knew for SURE it was the problem part. Sorry again this got a little long, I've been researching this for a long time, and have learned alot about hydraulics, I guess that's a good thing?
__________________
Stakealot is offline   Reply With Quote
Old 03-03-2009, 07:36 PM   #10
Senior Member
 
chasfm11's Avatar
 
Texas Boomers Club
Freightliner Owners Club
Join Date: Mar 2004
Location: DFW Area, TX
Posts: 2,027
WIth just some interest in your situation and absolutely no knowledge, I started poking around.

Sauer-Danfoss does not have the most user friendly website but I did find this. I could find nothing else that even comes close to a description of your system. The question for me is how much of a variation is there between what you have and the diagram that I found.

From reading your description, a wild guess would be that some piece of debris is lodged in your thermovalve. Before replacing it, I'd see if there is a way to take it apart and look at it.

It sounds like the valve operates the same as the control valve on an air brake system. Of course, even if that is correct, it doesn't help much with a way to trouble shoot it.

I wish you the best. I sure wouldn't want to be faced with your siutation.

Charlie
__________________
2000 Georgie Boy Landau 36' DP
2005 Saturn Vue toad
KF5-NJY
chasfm11 is offline   Reply With Quote
Old 03-04-2009, 11:44 AM   #11
Senior Member
 
Join Date: Apr 2003
Location: Oakton, Va
Posts: 1,149
The troubleshooting steps would be to make sure that the thermovalve is getting the proper signal and if it is then the thermovalve should be replaced. If CC can help with info the determine if the signal to the thermovalve, that would be the next step. There have been threads about side radiators with improperly controlled fan speed and it was a problem right from the manufacturer. There should be a positive test to determine the operation of the thermovalve. If you can do that test then it would show that the control signal is faulty. Keep us posted
__________________
Jim Walker
N Virginia
2014 Palazzo 33.2
Cummins 6.7 ISB, Allison 2100 6 Speed
J Walker is offline   Reply With Quote
Old 03-09-2009, 08:37 PM   #12
Junior Member
 
Join Date: Feb 2009
Location: Northern Minnesota
Posts: 21
OK, I have ordered a new thermovalve. An expensive little bugger, but if it fixes the problem, I'll do backflips all the way to the poorhouse. chasfm11, the diagram has an electronic control, otherwise it's the same. Cat, thanks, your vote put it over the edge. Thanks again to ALL the support, It's nice to have input!
__________________
Stakealot is offline   Reply With Quote
Old 03-10-2009, 06:44 AM   #13
Senior Member
 
chasfm11's Avatar
 
Texas Boomers Club
Freightliner Owners Club
Join Date: Mar 2004
Location: DFW Area, TX
Posts: 2,027
Do keep us posted about your progress. I'm interested to see if your new part fixes the problem.

You can always look at it this way, regarding the poor house. If you had taken it to a shop, you most certainly would be looking at double your $700 investment. Sometimes, it is better to roll the dice with just the part.

Charlie

P.S. I'm not sure that I understood your comment about the diagram that I referenced. I think that you were saying that the information that you have about your fan set-up was the same as the diagram that I found except that your setup does not have the electronic control shown in my version. What I was trying to figure out was how the thermovalve changes the way that the fan is controlled without the electronic control
__________________
2000 Georgie Boy Landau 36' DP
2005 Saturn Vue toad
KF5-NJY
chasfm11 is offline   Reply With Quote
Old 03-13-2009, 11:30 AM   #14
Junior Member
 
Join Date: Feb 2009
Location: Northern Minnesota
Posts: 21
Chasm11, Thanks for the words of encouragement, The diagrams shown are controlled electronically. The one I have has no electronics. It (the fan) is controlled by a thermovalve that is a needle valve held open by a spring. The thermovalve is in direct contact with engine coolant and has a small wax-filled capsule on the end that is in the coolant. As the engine temp gets over 190 degrees, the wax melts and expands, it begins to close the needle valve, causing the fluid to become increasingly restricted. As the fluid is restricted, the fan runs faster, up to full speed at about 220 degrees. It is a very simple and effective design, if it only worked! Sorry it took so long for me to respond, I was feeling a bit nauseous after spending that kind of loot on a such a small part. Hope it works, then it will be worth it! I'll let ya know.
__________________

__________________
Stakealot is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Hydraulic Cooling Fan moisheh Monaco Owner's Forum 5 10-27-2008 12:59 PM
Hydraulic Radiator Fan hax Alpine Coach Owner's Forum 9 08-09-2008 08:34 AM
HYDRAULIC RADIATOR FAN MOTOR FRED MASINO Alpine Coach Owner's Forum 3 06-29-2007 12:59 PM
Hydraulic Fan Leak Gary and Judy Alpine Coach Owner's Forum 6 10-04-2006 05:43 PM
Hydraulic Cooling Fan Roadmaster Motorhome Chassis Forum 5 12-31-1969 07:00 PM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 01:31 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.