Thermostatic fan control

[Old Scout]

The 03s have a modest sized trap door [couple of screws to remove] between the bed and the back closet. Think with the 04s an newer, the entire floor between the bed and the back closet must be removed to gain access to the engine compartment --not as easy a task as just removing the trap door.

[2 Stroker]

This may help
http://www.rv-chassis.com/tvck-101.html
or
http://www.rv-chassis.com/tvck_inst.pdf
2 stroker

[EngineerMike]

04 Alpines have the wax valve same as Scout's coach. His description in post#11 is as good as it gets. there's a wild chance some very late 04's might have the electronic controller, in which case idle rpm's should be ~850.

I believe if you connect the two hoses (i.e. bypass the wax valve) the fan should go full on. Cap the hoses & fan rpms will be minimal, perhaps zero but couldn't say for sure. It would be nice to know for diagnostic purposes.

If you have never changed the hydraulic fluid filters, there was one 04 owner who had his filters disintegrate & clog up his fan hydraulic motor. Twas a mess to clean it all out. Hope that's not what's up w/the "noise."

[TDREAMER01]

Thanks to all that helped with my dilemma. After disconnecting the hose on the inlet of fan motor that went to the wax controller, plugging it with a 5/16 cap and putting a plug in the hose the fan took off like a rocket ship. Now I'm going to take the coach for a longer test drive which will include some small hills, I'll watch the temp gauge and after taking the hills stop and check the fan to see if its turning. I'll keep you posted, again, Thanks to all.

[EngineerMike]

Now that you mention it, the A/C 'kit' installed by WRV for some of the wax valve radiators is a normally open (N.O.) solenoid valve run by the air conditioner (either the high pressure switch or the fan clutch, w/the latter using a relay so the valve load won't be on the fan clutch circuit). The the N.O. valve shuts when A/C calls for fan, so fan defaults to high w/no hydraulic flow thru the wax valve.
The wax valve's wax expands when hot to close the valve.

[TDREAMER01]

In response to the hydraulic filters (3) I change them every 6000 miles and refill with Dexron 3 Fluid.And I blocked off the line at the back of the fan motor,I didn't connect them together, it was easier to reach than at the top of the radiator.When I started the motor the fan ran full speed.After test driving the fan does come on,but I don't understand, my son has a 99 Alpine 36 with the same fan system as mine. When he starts his engine cold the fan begins to turn. Mine didn't, that and the squealing noise is what started all this. So thanks to all for the input, it was certainly helpful.

[Dr4Film]

Changing Hydraulic Fluid Filters every 6000 miles seems to be a bit much in my estimation.

I have 72,000 miles on my coach and the hydraulic filters and fluid have never been changed.

It's a closed system so I would expect there would not be a lot of debris or junk to gunk up the filters or the fluid, unless of course you have a leak somewhere.

JMO

Dr4Film ----- Richard

[TDREAMER01]

I am a stickler on maintenance and on the reservoir it says to change the filters every 6000 miles, so every 6000 miles I change the filters and after what EngineerMike said about them disintegrating I'm happy to follow their lead. I'm still a little confused about the true operation of the Wax Controller and maybe the slow response to the temp is a reason why I have had problems in the past when pulling long hills. I have learned to just be patient. Maybe if someone knows if there is a complete electronic kit to replace this wax system I might consider it if this ever fails. One thing I did have to consider about this wax system is NO ONE has one anywhere, which tells me it must be a pretty reliable system, no one has one nor does anyone stocks it, it has to come from the manufacturer.

[Dr4Film]

I've been told that the Wax Valves come from England and are special ordered when needed.

Although I know that Source Engineering has a replacement also.

Source Engineering

Here's a discussion on a thread about replacement.

http://www.irv2.com/forums/f115/side...nt-148331.html

Dr4Film ----- Richard

[Algoma]

Look at this thread I posted last month.

[Old Scout]

Sounds like your wax valve is working--atleast within parameters that allows the engine to cool. One suggestion on hill climbing, especially during hot weather, the ILS engine has plenty of power to climb most hills but ocassionally, it will do so at lower RPM. Since fan speed is related directly to engine RPMs, its a good idea to shift down to maintain engine RPMs, even if you dont need the power.

As several threads on this forum suggest, there are a number of after market options to by-pass the wax valve or to replace a failed electronic controller. Dont think there is a "good" electronic solution to "replace" the wax valve as it would require an ECM interface to be truely effective.

My challenge [compulsion really] over the years with the wax valve, has been lack of a dash A/C, engine fan interface. I installed the WRV recommended by-pass that uses a freon pressure sensor to override the wax valve when the A/C calls for more air flow. Even though it has worked pretty well for many years now, I remain concerned that unlike the wax valve, the [N.O.] solenoid does not provide for modulated activation of the fan. Accordingly, I get a pretty harsh fan start when the A/C calls for cooling--not sure this is the best solution in terms of torque on the hydraulic pump and drive shaft. For my money, an aux electric fan [no room to mount] or an additional condensor is probably a better solution.

PS--I tend to agree that changing fluid every 6k might be excessive. I 've settled on every 3-4 years which is about 36-48K miles but we all have different comfort zones when it comes to maintenance.

[BFlinn181]

Old Scout, I'm surprised your A/C condenser is in with your radiator, oil and transmission cooler, and I assume inner cooler. My A/C condenser is off to the side with two electric fans for separate air flow. The OP reports his fan doesn't turn at all when cool or at idle, that just doesn't sound normal to me. I would think that even a slow moving fan would help inner cooler air temps and engine efficiency. I've pondered how he could monitor fan speed since he can't raise bed and watch. I thought of a video camera, but you'd need light and couldn't really see fan speed accurately. If it really doesn't turn at idle I'd suggest a call to engine or chassis maker and what's normal. Perhaps the noise he heard was a bad fan bearing that only allows rotation when pressures overcome friction? The wax valve could be malfunctioning and closing down too much flow when cold?

[TDREAMER01]

Asking about my dash air isn't something I could answer as I don't use it at all, I removed the belt because of that. If we need a/c on the road I start the generator and run the front roof air, I figure if its hot enough to require a/c inside I wouldn't want to add anymore heat load to the engine, which already runs warmer than I think it should.

[Algoma]

I think if the load from the a/c compressor causes your engine to overheat then you really do have a problem. Also without a/c from the engine you may have problems with defogging the windshield in high humidity situations. Maybe that is not an issue where you drive.
On my engine (not the same as yours but has the same wax valve) the fan definitely rotates at idle and speeds up as the engine gets warmer.