Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
RV Trip Planning Discussions

Go Back   iRV2 Forums > THE OWNER'S CORNER FORUMS > Alpine Coach Owner's Forum
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 06-16-2022, 12:24 PM   #1
Member
 
New Guy Will's Avatar
 
Alpine Owners Club
Join Date: Aug 2021
Location: Baton Rouge, Louisiana
Posts: 48
Hydraulic Fan (For A/C)

Do any of you guys know about a hydraulic fan (located in back drivers side behind radiator)? My Truck A/C is giving me trouble, and has a new Compressor, installed by Truck Pro. Brought it back to them, and they say this Hydraulic Fan is not working, and that allows head pressure to build up, and shut down compressor.
I believe this fan runs off hydraulics from the power steering resovoir.
Do any of you have any knowledge of this?
2000 Alpine 40FDS LE
Thanks, Will
__________________
William Stevens
2000 Alpine Coach 40 FDS
New Guy Will 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 06-16-2022, 01:33 PM   #2
Senior Member
 
Old Scout's Avatar
 
Join Date: Nov 2005
Posts: 6,991
Hours of reading on this forum regarding your issue. Early Alpines used a mechanical wax valve attached to radiator to control engine fan speed. Thus, no interface with the dash A/C requirements for cooling. Some owners live with it, some have added a solenoid to trigger fan with A/C system, some add electric fans with a relay from A/C system, and some have moved the condenser and added electric fans.
PS -- assume your Cummins engine is cooling correctly?
__________________
Old Scout
2015 IH45 Foretravel
2003 Alpine 40' MDTS [Sold]
New Braunfels, Texas
Old Scout is online now   Reply With Quote
Old 06-16-2022, 02:19 PM   #3
Senior Member
 
Join Date: Oct 2014
Posts: 5,786
Yup, the fan is controlled ONLY by coolant temperature.


So, indeed, dash A/C head pressure can go very high if fan not operating.


In fact, when I needed to charge my A/C, I used a garden hose on the A/C condenser to keep temps in a range so that the A/C worked as it should.


There ARE some "work-arounds" including moving the condenser, installing electric fans (on either present location OR on relocated location (best) OR by modifying the hydraulic system so fan does turn some even if coolant temperatures are below cut in temp.


BTW, the modification to the hydraulic system to have the fan running even at cool coolant temperatures has a side benefit of lowering intake manifold temperature as air is drawn through the CAC.
__________________
Brett Wolfe
Ex: 2003 Alpine 38FDDS. Ex: 1997 Safari Sahara. Ex: 1993 Foretravel U240
wolfe10 is offline   Reply With Quote
Old 06-16-2022, 03:11 PM   #4
Senior Member
 
Alpine Owners Club
Join Date: Oct 2017
Location: Sugar Grove IL
Posts: 268
If your wax valve is working for your higher temperatures while you are on the road you can add a small valve in the line from the wax valve to the fan. With a strobe light you can set the minimum constant fan speed. I did it myself and was able to set the fan speed to 6-700 rpm’s. The valve is adjustable and the increased flow through the CAC is a plus. It solved the head pressure your shop has mentioned. I can look for some pictures if that would help you.

Take the time as Old Scout mentioned to review old posts. There are hours of them pertaining to this issue.
__________________
Mack Mover
2003 Alpine 40 MDTS
400 ISL
Bruce Anthon is offline   Reply With Quote
Old 06-16-2022, 04:32 PM   #5
Senior Member
 
Dave Fernandez's Avatar
 
Alpine Owners Club
Join Date: Jun 2003
Location: Ontario, CA USA
Posts: 1,385
Unfortunately, on the early Alpines with a Hydraulic Fan does not pull much air at Idle. This has caused many A/C compressors to destroy themselves. What some owners have done was to move the condenser to another location and use an electric fan that keeps the head pressure within the normal range. A few of us have installed an electric fan on the condenser and that has solved the problem of high head pressure.
Attached Thumbnails
Click image for larger version

Name:	AC Condenser Fan.jpg
Views:	18
Size:	404.4 KB
ID:	368495   Click image for larger version

Name:	AC Fan.jpg
Views:	18
Size:	543.3 KB
ID:	368496  

__________________
Dave Fernandez
2001, 38ft FDDS, 350 ISC, Tow 2004 Yukon
https://www.alpinesocal.com
Dave Fernandez is offline   Reply With Quote
Old 06-16-2022, 07:17 PM   #6
Member
 
New Guy Will's Avatar
 
Alpine Owners Club
Join Date: Aug 2021
Location: Baton Rouge, Louisiana
Posts: 48
Quote:
Originally Posted by Old Scout View Post
Hours of reading on this forum regarding your issue. Early Alpines used a mechanical wax valve attached to radiator to control engine fan speed. Thus, no interface with the dash A/C requirements for cooling. Some owners live with it, some have added a solenoid to trigger fan with A/C system, some add electric fans with a relay from A/C system, and some have moved the condenser and added electric fans.
PS -- assume your Cummins engine is cooling correctly?
Yes Sir, Engine temp is fine, but the diesel takes a lot to overheat...
I believe what you are telling me is the engine temp is not getting hot enough to trigger the fan moter? I have noticed that when driving along at speed on the higway A/C fan speed needs to be on 3 or 'high", but when you slow down to go through a town, istop for red lights, A/C fan blows much harder, and you can set A/C fan back to low.
Does that seem consistent with what you are telling me?
__________________
William Stevens
2000 Alpine Coach 40 FDS
New Guy Will is offline   Reply With Quote
Old 06-16-2022, 07:27 PM   #7
Member
 
New Guy Will's Avatar
 
Alpine Owners Club
Join Date: Aug 2021
Location: Baton Rouge, Louisiana
Posts: 48
Thanks

Thank you to all that replied, I was completely unaware of this design fault.
Will work on finding a solution. (Before I destroy this new compresssor)
__________________
William Stevens
2000 Alpine Coach 40 FDS
New Guy Will is offline   Reply With Quote
Old 06-16-2022, 08:54 PM   #8
Senior Member
 
Old Scout's Avatar
 
Join Date: Nov 2005
Posts: 6,991
Ref your post #7--looks like you have read all the inputs and now have a good understanding of the issue regarding lack of engine fan to dash A/C interface. Separate from that, you described a second issue with the dash fan. The front cab of Alpines is well sealed and with the air dam at the bottom, a partial vacuum tends to form in the genset area. As a result, the dash fan struggles to over-come the vacuum at hi-way speed but does ok in town. Solution is to keep the dash selector on "max air" at all times--this setting closes outside air dam and recircs inside air. Ironically, and for the same reason, this setting also works best for heating the front of the coach when driving in very cold weather.
__________________
Old Scout
2015 IH45 Foretravel
2003 Alpine 40' MDTS [Sold]
New Braunfels, Texas
Old Scout is online now   Reply With Quote
Old 06-16-2022, 09:20 PM   #9
Member
 
New Guy Will's Avatar
 
Alpine Owners Club
Join Date: Aug 2021
Location: Baton Rouge, Louisiana
Posts: 48
Quote:
Originally Posted by Old Scout View Post
Ref your post #7--looks like you have read all the inputs and now have a good understanding of the issue regarding lack of engine fan to dash A/C interface. Separate from that, you described a second issue with the dash fan. The front cab of Alpines is well sealed and with the air dam at the bottom, a partial vacuum tends to form in the genset area. As a result, the dash fan struggles to over-come the vacuum at hi-way speed but does ok in town. Solution is to keep the dash selector on "max air" at all times--this setting closes outside air dam and recircs inside air. Ironically, and for the same reason, this setting also works best for heating the front of the coach when driving in very cold weather.
Great Reply!! Solved a mystery, would never have figured this out alone.
Will
__________________
William Stevens
2000 Alpine Coach 40 FDS
New Guy Will is offline   Reply With Quote
Old 06-17-2022, 10:38 AM   #10
Senior Member
 
Alpine Owners Club
Join Date: Oct 2017
Location: Sugar Grove IL
Posts: 268
Click image for larger version

Name:	IMG_0630.jpg
Views:	28
Size:	258.3 KB
ID:	368545Click image for larger version

Name:	IMG_0634.jpg
Views:	45
Size:	278.8 KB
ID:	368546

These are some photos of the valve that will let you regulate the minimum engine fan speed. Very easy to install.
__________________
Mack Mover
2003 Alpine 40 MDTS
400 ISL
Bruce Anthon is offline   Reply With Quote
Old 06-17-2022, 12:46 PM   #11
Senior Member
 
Old Scout's Avatar
 
Join Date: Nov 2005
Posts: 6,991
Ref post #10 picture, I am told there is an adjustment screw under the Allen-wrench cap on the wax valve that will increase the idle fan speed--but never tried it. Similar to the adjustment valves on HWH scissor slides, I like the needle valve solution offered by Mack Mover.
__________________
Old Scout
2015 IH45 Foretravel
2003 Alpine 40' MDTS [Sold]
New Braunfels, Texas
Old Scout is online now   Reply With Quote
Old 06-18-2022, 09:02 PM   #12
Member
 
Join Date: Dec 2020
Posts: 58
Bruce,
Thanks for the pictures, do you have a wider angle picture showing the location of that valve and how to get to it.
I just got the valve and need to install, hopefully get the AC working again
Cheers
Bob
__________________
Bob
2003 36FDDS ISL 8.9
San Diego
Sideshow is offline   Reply With Quote
Old 06-19-2022, 09:05 AM   #13
Senior Member
 
Alpine Owners Club
Join Date: Oct 2017
Location: Sugar Grove IL
Posts: 268
Click image for larger version

Name:	IMG_0632.jpg
Views:	16
Size:	306.5 KB
ID:	368684

First, be sure to measure your fan speed cold, at idle, before you start the project so you have a reference point for your improvement. I got my RPM strobe reader at Harbor Freight.

The valve is located just under the top side radiator hose. That is on the top left corner of the radiator as viewed from the backside under the coach. It is a long reach but serviceable. Be sure to use two wrenches to support the valve as you break the fitting loose. Mine was very tight. You will also get some hydraulic fluid dripping so keeps some rags handy. I bought the two fittings you see in the picture that have the purple thread tape on them to go with the new valve. As I recall, when the valve was added, there wasn’t enough clearance to route the hose properly with the straight fitting that was on the original hose. I had a new one of a different length made up with a 90 degree end. I replaced the other hose at the same time as well. Both were getting stiff and hard by the fan motor. When you are under there you will see the the back of the fan, hoses and pipes that all have to be worked around. You might be able to keep the original lines… but this worked for me.

PM me if you would like to talk through the steps. Good luck!
__________________
Mack Mover
2003 Alpine 40 MDTS
400 ISL
Bruce Anthon is offline   Reply With Quote
Old 06-20-2022, 08:28 PM   #14
Senior Member
 
Join Date: Jan 2006
Location: Simi Valley, Calif
Posts: 185
If you take the three bolts holding exterior radiator cover (painted) loose and you swing it up for easy access. If you lift it parallel to the ground it will drop out of hinge and can be set aside (use two people). 1/4” bolts are located on bottom between louvres and back end to rear cap
__________________
Sandy and Debi
2004 Alpine 36 FDDS
sandy1 is offline   Reply With Quote
Reply

Tags
fan, hydraulic



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
Fan-Tastic Bath Fan, broke fan :( Bmaintz8 iRV2.com General Discussion 11 09-01-2019 06:20 PM
Fan for Hydraulic Fan Motor - can't find ChrisAndSall Roadmaster Motorhome Chassis Forum 9 02-19-2017 04:39 PM
Fan that attaches to Hydraulic Fan Motor ChrisAndSall Monaco Owner's Forum 14 01-12-2017 09:37 PM
Hydraulic engine fan converted to electric fan RyanG Monaco Owner's Forum 9 07-19-2015 05:26 AM
Choosing a Powered Fan (MaxxAir MaxxFan vs. Fan-Tastic Vent 6600 + MaxxAir Fan/Mate) TrailerFool iRV2.com General Discussion 6 11-22-2008 05:06 AM

» Featured Campgrounds

Reviews provided by


All times are GMT -6. The time now is 09:37 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2022, vBulletin Solutions, Inc.