I have been having an over heating problem on my 95 U240. Foretravel replaced the hydraulic pump and sun controller. They then told me the fan motors were bad. I got the motors(2), 4 90 deg. fitting, 2 smaller 90 deg. fitting, 2 mounting plates, 2 hubs all from Foretravel. I have removed both fan assy.(fan motor, blade, mounting hardware as one piece), only 4 bolts on each fan assy. and 3 hoses on each fan assy.. Then at the bench 4 fan bolts, 4 mounting plate bolts, and one hub nut and the assy. is apart. Put it back together with new motor, hub, and mounting plate. Then I have remounted the first one and will do the other one in the morning. Connect 7 hoses to the motors. Refill the oil reservoirs with about 3 gals Delo400 and smoke test. I have done this work with my brother. The four top mounting bolts can only be gotten with a 9/16 box end on the bolt and a 9/16 box end ratchet wrench on the nylock nut. The other 4 bolts are on the bottom and are easy. The complete job with two men is about 10 hours. Not too bad. I will update when I finish.
I recently I took our 1997 U295 to Bernd Ramspeck in NAC for routine oil change, lube, filter changes, etc. The hydraulic pump and both fan motors were all leaking on arrival. They had been seeping for 12,000+ miles, and conveniently started leaking on the the trip to NAC. Bernd and crew replaced seals in all three units. I've observed no leaks or seeps in about 1,400 miles of driving since the repairs. FOT cost for replacement of pump and motors would have been about $6,000 for parts (labor would be additional cost). Cost of seals and rebuilds at Bernd's shop was about $1,200.
Fan motors for late '90s coaches is about $2,000 each and wait time is a few weeks. I hope someone finds a better solution for failures of those units. I was fortunate that my units only required seals, and Bernd was able to get, and install, the seals. Even the seals are in short supply because the fan motors are units that were fabricated to Foretravel specifications.
J D, Do you have part numbers and place where seals were purchased? One of my fan motors is weeping. I may as well re-seal both at the same time.
Yes, part numbers along with the motor model would be handy. Also, some of our coaches only have one fan motor. Wonder if it is the same and takes the same seal.
Pierce
Forward fan motor on our 02 U320. Two years ago while getting ready to travel with 2 grand kids on a 1,000 mile loop I notices fluid from our fan motor and had to add oil to the hydraulic reservoir twice in one week. Not wanting to get stranded we called FT and they ship the fan to us. $3,000.00!!!!!!! Of course, once we had it the leak stopped and 15,000 miles later haven't had to add oil nor seen any fluid leaking. We will be in Nac next month and I will return the fan.. After a 20% restocking fee...
Yup, those fans are only used by Foretravel and, from what I understand, are custom made in Germany...
Never asked what the installation cost would be....afraid to....
From the few places I talked to they would not guarantee replacing the seals would last.. But, seems that would be the way to go as others have not had problems.
Chemical seal expanders can work wonders on old age hardened seals. Softens and expands them without harming other components. Has worked well for me including a very bad transmission seal 200K miles ago and PS pumps. Won't stop leaks caused by severe pump/motor wear.
Pierce
I don't have part numbers. I left all the work to Bernd and crew. My understanding is that he bought the seals from FOT. I think only a few of the seal kits remain. The seals, like the motors, are "special." >:( I think no motors remain. New motors are built as needed and are not an item that is kept in stock. If new motors can be built, I would expect new seals could be manufactured on request.
Indeed, the new seals and installation of them are not covered by any warranty.
Well the update is not good, I got concerned about the fan motor mounting clock position. In other words the fan motors can be mounted in either of 2 positions. The supply/suction hoses on the motors are on the top and bottom. I call FOT about my concerns and after talking to someone not named, I was told to mount them the same as the old ones. I also asked twice for any help/instructions FOT had or could help with, and I got no help. Well the old ones are made in rockford, IL with four mounting bolts and the new ones are made somewhere in Italy(i got the shipping box) with only 2 mounting bolts. So I mounting them opposite (like the old ones, going by the oil relieve hose on the back). I smoke tested it, after 3 gals. of delo400. The fans ran in the wrong direction, and seem to be very slow. Now I have to take both fan assy. off and reverse the clock mounting position of both motors, loose lots of delo400(messy) , and then put both fan assy. back on and smoke test again. If FOT had helped just a little bit the upgrade would have been pretty easy, but now I am real happy with FOT. The pump and sun cartriage job at FOT was $2000 parts and labor(that was not the problem), and then the upgrade kit for the fan motors was $2400(just parts). Now I have to do the job all over and all that oil everywhere(that makes me real happy) just to get the fans turning in the right direction, which could have been avoided. If you put fluid into a motor at a port, you need to know which direction the motor will turn. FOT could have helped. Well tomorrow I will reverse the motors. Updates later!!
Our 91 GV uses the power steering hydraulics to operate the cooling fan. The seal on the fan shaft has been leaking a little fluid for some time. I put some power steering stop leak in the system and it has slowed to nearly a stop. I dont know if it will eventually seal off or not, I'll just keep an eye on things. When we stop for a day or two, I'll put a paper towel in a pan under the shaft and just note the amount. (a few drops a day). I'll plan on replacing the seal at some point down the road. I'm thinking that it will be OK for that amount of time, but it could be a "gotcha"!! Have a great day ---- Fritz
On our U295 the fan blades turn counter-clockwise when looking from inside the engine compartment to the outside. The fan blades draw air from the outside into the engine compartment. The fresh air moves across the charge air cooler, then across the radiator and inward toward the engine.
If the fans are placed on the pumps with the blades in the wrong direction, the engine will overheat. I demonstrated that mode of operation on my first attempt to leave Nacogdoches. One of the apprentices had installed the blades wrong. The error went unnoticed until I drove for several miles at 65 mph on a hot day. I returned to NAC at a slower pace and was able to keep the water temperature below 200F. Bernd and Tony were embarrassed by the mistake, and the apprentice fixed the error quickly.
We have now traveled about 2,500 miles since the repairs. Coolant temperature is well regulated at 180F and there have been no leaks or seeps from the hydraulic system. It looks like Bernd and associates fixed several items and saved me about six coach bucks compared to replacing the hydraulic hardware.
@Pat if you have fan motor drain(s) be sure to check that they are clear. If not pressure will build up and blow out the seals in the new fan motor. You can check by removing the fan drain and blowing back through the hose toward the reservoir. You should be able to do this pretty easily. It is a little distasteful (ha!) but will save you down the road. Mine was blocked and I had to replace the hose after I lost the motor.
A little late to help you but it's easy to tell the direction the motor will spin. Hold the motor up and spin the fan shaft in the direction the fan needs to spin while looking in one of the fluid ports on the motor. The fluid passes through the motor around the outside of the gears. So if while spinning the motor the gears would push the fluid towards the center of the motor you are looking at the output. If around the gears you are looking at the input. Uhhh maybe easier to see than describe... :)
Also to keep from losing hydraulic fluid when you change out your motor(s) buy some caps and plugs at a hydraulic shop. You can use them to plug the hoses as you pull them only losing a cup or so of fluid. The hard part is figuring out what size plugs to get. I just told the hydraulic shop what size wrench I used to pull the hose and they were able to match up that way. You will need to check your installation to determine how many caps and plugs you will need.
@David Glad you had good luck with the seals. Hope they hold up for you. I had the seals replaced in my pump but they didn't last very long. Only several hundred miles. I suspect my clogged drain hose caused a high pressure situation that in turn caused mine to blow. I would advise keeping a close eye on your motor for seepage. At 2500 miles I think you are probably ok.
see ya
ken
Motors have been reversed. The fans now run the the right direction, both the same direction(counterClockwise). After new pump, new sun controller, and new motors; both fans still run at a slower than spec. speed(about 500-700rpm slow). I adjusted the sun controller from all the way in to all the way out, it does not effect fan rpm at all. I think the only thing left is the high/low speed solenoid value. I guess I will replace that next. If that $80 part fixes it, I will be........ Updates later.
This is another try. But has anybody sourced motor seals from anywhere besides FT? Or has a part number, etc?
Pat,
Do you have a close-up photo of the data plate on the side of the motor? A couple of your photos show the plate, but when I enlarge them not good enough resolution to read. I just want to know the motor manufacturer and part number. THANX!
I wonder if you could go here and fill out the information and have them recommend a updated more serviceable system. I wouild think it would cost quite a bit less than the numbers you are paying now.
http://www.hasmak.com.tr/haldex/FanDrive.pdf (http://www.hasmak.com.tr/haldex/FanDrive.pdf)
I'd be gobsmacked if there isn't a suitable substitute for the old motors ! To many hydraulic motor applications out there for one not to exist. JMOO
Several will work and you can see many for very inexpensive prices on ebay. But unless someone does a lot of research for exactly what will bolt up, has the right threads, the correct GPM at the correct RPM, it's not going to do any good when you have a failure and get towed into a shop that does not have a clue. Does not help when Foretravel put both single and two stage pumps on plus some models had one fan and others two. Mix in a little Italian metric threads.
Just looking at the hydraulics over there, it reminds me of the Samuel L. Jackson film,
Snakes on a Plane with all the lines running everywhere. I have to shield my eyes from the fan blades as I remember when my cousin and I were trapped in a frozen meat locker in Jersey. The little guy was writing my name in the dust on one of the refrigeration blades when................................................OK, I don't have cousin in Jersey. Just getting ready for campaign season. ;D
Happy Holidays,
Pierce
Yeah, about the only way to do it is working back from fan pitch and diameter, desired speed of rotation, shaft size and mount patterns,that'll give your needed displacement, motor style and gpm. Using a variable displacement pump and suitable controller would give you some leeway, much increased efficiency potentially, and also help account for wear as system ages, think that's why so many are seeing less than max rpm on their fan systems. Belt drive pumps make it easier in some ways as mounting, pulley size can be changed. Gear drive like on the Detroits while very desirable in many ways will make it tougher. It can be done, tho, and would make a neat collaborative project. No reason why off the shelf replacements of these relatively inexpensive parts couldn't be worked out.
I used to own a company that did foundation drilling, mostly underreamed piers, using hydraulic driven equipment...turntables that rapidly swung a 20K lb drill around, 30' kelly bar hydraulic cylinders, stacks of pumps putting out 75 gpm or better. When a line blew on one of those bad boys you knew it right off. Anyway, point is, when we needed pumps or motors it was pretty straightforward to just spec one based on displacement, shaft, mount etc., and buy it as a generic item. No reason this can't be done on the coach, the whole existing system was designed at one time utilizing off the shelf parts. Those shelves are pretty empty now as time has marched on, but replacements are out there.
It's much simpler than doing massive calcs. If FT would give the design specs they used, it would be easy to supply a different motor. I really don't understand why they went with a unique foreign motor anyway.
The motors are either gear or vane. The main spec on motors is displacement per revolution, max RPM, and pressure operating range. You don't need to be EXACT with this (discussion at bottom).
Fittings can be adapted, that's no problem. Mounts may have to be modified. Fan mounts to shaft may have to be modified as well.
The specs don't have to be perfectly exact, especially on the newer systems that have a variable speed control system. As water temp gets higher, the valve (8.3) or the computer (m11) sends more flow to the motors.
It appears that 1996ish onward uses a system that is fairy simple and common amongst all years.
It's not presure that spins the fans, it's flow. However, pressure will increase more RPM is called for on the fans. But, one must understand that this pressure is created by the LOAD of the fan blades. In theory, if you run the motors with no fan attached, the RPM will be the same, but the pressure will be lower.
Also, I'm thinking about switching to hydraulic fluid instead of motor oil. Why not use what these things are designed to use?!?
And here is a decent intro to theory and different types of motors. http://academic.udayton.edu/JosephUntener/Course%20information/MCT336/Class%20Handouts/Hydraulic%20Motors.ppt (http://academic.udayton.edu/JosephUntener/Course%20information/MCT336/Class%20Handouts/Hydraulic%20Motors.ppt)
Reverse engineering can be done many different ways. It would be possible to disconnect the output line on the far pump, put it in a graduated cylinder, and rotate the near pump by hand. That will spin both. Capture the fluid output from ten revolutions, measure it, and you know the displacement and gpm of the motors. Pressure is going to be related to the amount of hp required to spin the fans, no need to not use the known factory spec for RPM for this. Best to not overlook the power steering needs, tho, might be the reason for motor oil rather than hyd.
Krush,
Still won't do much good even if filed away somewhere when Joe and Josephina have a failure tomorrow or 5 years from now. Different models with different number of fans further complicate the issue. Other than figuring out what will work, buying all the parts, installing to check and then removing to store in a box in the belly, I don't see an easy way out of this situation. Foretravel must get hundreds of requests for this and that but when you have changed direction and with a small staff, there is not much chance that someone there is going take the time to research motor/pump specs for an old coach.
Just hoping the idea of ram air radiators in the nose will reduce the load on the main radiator enough to allow removal of the hydraulics/motors/pump/fans and electric fans in the back will be enough to keep the engine cool in all conditions. After an initial installation, a kit could be installed in less than a day for less than $500. Two of these sample radiators at: 3 Row Tri Core Aluminum Racing Radiator 2X 10"Black Fans 73 76 Chevy Corvette V8 (http://www.ebay.com/itm/3-ROW-TRI-CORE-ALUMINUM-RACING-RADIATOR-2X-10-BLACK-FANS-73-76-CHEVY-CORVETTE-V8-/381095818024?pt=Motors_Car_Truck_Parts_Accessories&hash=item58bb14b328&vxp=mtr)
Plenty of room in a GV for a quick installation with only a couple of "T"s required like Kent Speers did. Series flow from one to the other plus utilizing the OEM heater boost pump already installed in the back.
Pierce
Pierce, that might be a good option for your aftercooled Detroit but isn't going to work on a Cummins CAC coach. I don't think there's ever going to be a one size fits all approach. It could work on a large range of similar coaches, tho. I'll tell you, I'd do a preemptive replacement on this gear, at least starting with the seeping motors. Not looking at that much money if you get away from the proprietary stuff.
Curious, have you done any heat dissipation calcs based on radiator size and airflow? Will the front radiators have fans also? If so, won't the fans negate a fair amount of the ram air effect? Seems like you might be just shifting your load from hydraulic to alternator.
The problem isn't that much research at FT needs to be done. The problem is they don't care. And really, why should they? The have a part that they can still obtain...it's just silly expensive. But, they make % markup. The more the part costs, the more they make.
For them to go and find an alternative, which would likely take at most 8 hours of a real problem solvers work (assuming they have all the design data), for something that won't make them more money is not going to happen.
Plus, I know the quality of engineers and problem solvers at companies these days. Anybody that is top notch, usually works for themselves....or in an industry that pays very well. There are always exceptions, but it's rare.
No, not realistic to expect FT to feel any compunction to redesign the cooling system in a 20 year old coach, or to provide engineering support to that end for others. I think they already go above and beyond in their support of these old coaches, especially compared to other mfg.
It's not rocket science, though, and easy enough to work it out without factory assistance. Foretravel's cooling requirements were most likely specified by engine mfg. anyway. Probably an good aftermarket idea for some ambitious person, and not just for Foretravel coaches.
Chuck,
The radiators in the supplied link do have fans but with ram air, fans would only be used in stop and go traffic. As you may have noticed, the fans are not shrouded so ram air would go past them without much of an impedance. Using the heater lines will not be nearly as effective as larger dedicated lines but should be enough to allow the hydraulic system to be removed and smaller electric fans fitted. Larger coolant lines to the front would totally remove the need for the hydraulic system.
The total load on the electrical system would be much less. CAT has a publication for RV hydraulic systems with a 20HP loss at low fan speed to a 50HP loss at the high speed setting. Any rear/side radiator just sits there with zero air moving through it at any speed without a lot of help. I'm trying to eliminate most of the energy needed to move air through the radiator core for the total amount of radiator area.
With the removal of the hydraulic motor, a second matching alternator could be installed in the same location dedicated to the engine batteries or with a "boost" type switch, could be easily brought online to supply total electrical demand in case of the OEM alternator failure.
I installed a Mercedes OM-617 engine in a Mercedes van where the longer engine extended where the radiator had been. I then put a radiator under the van at a bit of an angle so ram air was effective in cooling and totally replaced the original front radiator. One small fan was fitted to it. I just used the stock Bosch alternator and had zero problems with it as the fan rarely came on.
In the outside case that the alternator had a fairly high draw on it, alternators are inexpensive, easy to find and can be install quickly by a fair percentage of Foretravel owners. The electrical wiring would be not prone to failure or leakage as hydraulic lines are. In short, a compact, neat installation.
Rather than try to do any calculations based on heater hose flow, etc., I have always eyeballed it and done "empirical calculations" Has worked well in the past when certain elements of the calculation were missing.
Pierce
OK I'm not the sharpest pencil in the box, but on my Eagle I had a side radiator and had a belt driven fan that ran off a 90 degree angle box. the crank pulley and two pulleys on the angle box with a belt tensioner to keep the tight. now looking at my 92 there are a few things in the way, however i think with a little thought one might be able to get something to work. I also had a front radiator with inch and half lines that ran under the bus that tied into the plumping for the radiator. just a option.
Andy,
Yes, my 4107 with a Detroit 8V-71 had a direct drive fan, alternator and AC compressor with zero belts anywhere. Nothing to adjust.
I see where you are coming from. Do an all mechanical drive for fans coming off the crank pulley. Not a bad idea. Good thinking. With a 90 degree drive and a tensioner, it could work well.
I did look at running a couple of large lines under the coach but wanted to keep from scraping them on the transitions from highway to side road with a steep shoulder. Perhaps I should think about a protective cover over the pipes.
For other post concerns: An electric fan should work for Cummins intercoolers without sacrificing any cooling.
Pierce
Andy,
Foretravevel had a 90 degree gear drive fan whey back yonder. J. Holder may remember the exact age,but we looked at a FTX that had the same set up you are talking about. I don't remember what chassis it had but, it has been done in the past and would be a lot of work for the handy man.
Pamela & Mike
There's nothing wrong with hydraulic fans. They have proven to be very reliable. And, I don't think it is very difficult to replace the existing motors with something off the shelf--it just takes a little bit of thinking.
I'm trying to get ahold of a spare hydraulic system to keep in storage. If I get it, I'll see if I can cross reference pieces.
Pierce,
I can see the appeal of ram air and electric fans for sure. No doubt the hydraulic fans are huge power consumers, I saw the same Cat brochure, 20-50 hp. The problem with the hydraulic system, other than the fact that these are aging and $ to replace with oem is that brute force design seems to what was used to spec them. There's no way a 300 hp engine at low output needs a 20 hp fan to cool it. No real controllability. Lots of diesel pickups with similar or more hp manage to run most of the time with no fan engaged. Ram air will be a huge asset most of the time except when you need it most, pulling a 7% multi mile grade comes to mind. Too bad there's no good way to run finned tubing underneath to the new radiators... T'will be a grand thing if you're able to pull it off.
I was wondering the same thing. Prevost used them: http://prevost-stuff.com/prevost_53_RearEngine.jpeg (http://prevost-stuff.com/prevost_53_RearEngine.jpeg)
Here's clutch that might work: http://www.surpluscenter.com/Power-Transmission/Clutches/Electric-Clutches/12-VDC-8-GROOVE-SERPENTINE-CLUTCH-FITS-9-1737-S-8-AND-9-1738-S-8-1-2184-S-8.axd (http://www.surpluscenter.com/Power-Transmission/Clutches/Electric-Clutches/12-VDC-8-GROOVE-SERPENTINE-CLUTCH-FITS-9-1737-S-8-AND-9-1738-S-8-1-2184-S-8.axd)
And a right angle gear box: http://www.surpluscenter.com/Brands/Peerless/1-0-95-PEERLESS-20-HP-RA-GEARBOX-MODEL-1100-013-OPPOSITE-ROTATION-13-1514-C.axd (http://www.surpluscenter.com/Brands/Peerless/1-0-95-PEERLESS-20-HP-RA-GEARBOX-MODEL-1100-013-OPPOSITE-ROTATION-13-1514-C.axd)
Downside would be only a single speed (aside from engine RPM) with only an ON/OFF control. For unit with CACs a second sensor would be required with "either/or" logic.
Another thing that has improved over the years is fan blades. If you have to spend money to have an adapter made for your old fan you might consider a new more efficient fan with the exact interface to the motor. Multi-Wing is what Country Coach used when I was there and they have adjustable pitches. High efficiency on-highway radiator fans :: Multi-Wing America (http://www.multi-wing.net/engine-cooling-and-radiators/emergency-vehicle-buses-and-motor-coaches/)
This is a very interesting topic but I don't have to worry about this for myself - I have a rear radiator with a belt driven fan.
I've heard the 20-50 hp number for fan usage but I wonder how much of that is just inefficiency of the older hydraulic units.
Up to this point in my 97 U295 / 3126 Cat ownership, when I take it into my preferred truck repair shop (California Truck Center), they have been able to match the original part and make a professional repair they stand behind. http://www.californiatruckcenters.com/custompage.asp?pg=sacramentohome (http://www.californiatruckcenters.com/custompage.asp?pg=sacramentohome)
Is this where I knock-on-walnut-cabinet-wood? It is certainly not reasonable to expect the factory to re-engineer cooling system parts for our older units. I'm pleased FOT can supply original equipment parts.
I disagree completely. One reason for hydraulic fans is to allow variable output. On the older FT, it was high/low. Around 96 or so, it appears there is better control. The fan speed is controlled by the coolant temperature on my coach. It's variable. HP requirements drop greatly when fluid is bypassed and fans spin slowly.
Here's a good post with a great PDF of how these systems work. Hydraulic fan drives (http://www.foreforums.com/index.php?topic=21297.msg158153#msg158153)
There are mechanical loses in gear and belts and pulleys too. And having a fan either on/off on a mechanical drive likely eats up more HP.
Not so on my '96, can't speak for other years/models. There is no proportional fan control. I hope to address this someday.
My 1995 has high and low speed.
krush is right the 2 speed fan is a great feature. I put a indicator light on my dash to tell me when the fan is in low or high speed mode. It's almost always in low speed mode. The only time it's kicks into high speed is when you are on a long hill. Mine doesn't kick in until 198º or so. Personally I'd like for it to kick in at 190º. I've wired a rely/switch in so I can control it from the dash. When I get some time (and get off my lazy butt) I'll do a write up on it. It was an easy upgrade (costs less the $7!) that I highly recommend.
see ya
ken
Ken, there is no time like the present to do that sketch/schematic.
^.^d
JohnH
I haven't verified, but it was contention that the system on mine is variable. Barry posted a picture where he installed the valve. Manual fan speed control for our 99 U270 (http://www.foreforums.com/index.php?topic=22584.msg172589#msg172589)
Ken,
Excellent!
Would it also be possible to add a fan speed indicator on the dash? It may only work on electric fans. I believe it could be either an analog or digital style with a tach light mounted on the fan. I would like to have a constant monitor of the hydraulic fan system since it causes so much worry especially on the older systems. A quick glance could tell you if there is a problem when running if the fan/fans aren't running at the proper speed.
Thanks for the pdf on the fan speed, pump pressure test.
Jerry
Cummins said my 97 320 is a variable speed setup
Doesn't a two speed qualify for "variable speed"? Pretty sure we are two speed as I assume our thermostat controller is either open or closed.
Infinitely variable versus hi/lo
Personally I've only seen the 2 speed setup. So wondering how the "variable speed" would work.
The fan speed (single or 2 speed) does vary with engine speed but don't think that qualifies as variable speed. Would a variable speed try to maintain a constant speed no matter the engine speed?? Not saying they don't exist just trying to understand how/why you would use one.
see ya
ken
Country coach called it "a piloted wax capsule"
The fan controller on my '96 is a two speed, if the engine is running it's either high or low speed. When the engine is cranked in freezing temps, my fan is on low speed. Most likely the fan speed varies somewhat with engine speed and pump output. It's a pretty solid system but is somewhat of a power hog.
A more modern system would be infinitely variable fan speed between off and max fan rpm. Fan speed is based on cooling demand, independent of engine speed. So, in practice, the fans would range from zero rpm to max speed, as needed. This saves some power and has some operational advantages and can also allow for operator override in unusual situations. This is a proportional controller, fan speed in proportion to cooling needs.
I would expect but don't know that the later mod electronic engines incorporate proportional control.
Our 99 U270 is definitely 2-speed, controlled by a wax capsule on the return line from the radiator.
I cannot get this link to copy and paste but there ids a lot of good sizing information here at the Eaton Fan drive site here is what I can get to paste. Google Eaton hydraulic fan drives and it should come up
Fan Drive System Application Guide - Eaton
http://www.eaton.com/ecm/groups/.../@eaton/.../ct_233710.pd...Eaton (http://www.eaton.com/ecm/groups/.../@eaton/.../ct_233710.pd...Eaton) Corporation
Fan Drive. System Application Guide. 4. EATON Fan Drive System Application Guide Technical Focus E-SYFD-TM001-E March 2003. Hydraulic Motor Selection.
try this
Power Management, Powering Business Worldwide (http://www.eaton.com/Eaton/index.htm)
then in the search box put 233710
If you want to see what inside a typical motor looks like:
Disassembling a gerotor-type hydraulic motor (http://www.insanehydraulics.com/letstalk/openoms.html)
Video on his page: hydraulics - disassembling a trocoidal motor, the RIGHT way, by (https://www.youtube.com/watch?v=iAVicFV4uMk)
The pump on my U280 was leaking and I took the unit to a local SunSource hydraulic shop. They were unable to get any information on the pump but they did order the seals with the part number I gave them. They cleaned the unit and installed all of the seals in the kit. Now I carry an extra seal kit in the coach. Haldex W9A2 seal kit 5000101.
Basically a wax motor thermostat using the wax motor to open and close a flow control valve.
Basic principal shown below
Looks like the W92A series pump may have been a commonly used pump.
I have one of five 1993, U300's that have a variable speed fan controller according to the FOT shop. They were used as a test. The fan speed is correlated to the engine rpm. It was a great concept but in City Traffic it doesn't get any Ram Air effect and the low rpm's make it heat up in hot weather. As I recall the fan speed is 800 rpm on engine and 800 rpm on fans and 2100 rpm on engine 1800 on the fan. I was told the only used the this particular variable speed controller on five coaches. They went back to the two speed fan controller because it worked better overall.
My current coach has a water sprayer for the radiator called an Ultra Desert Cooler (Now out of business) so I have no need for a front Ram Air radiator on my U300, but the front radiator I installed on my U225 worked great with no fans. It was an all aluminum 24" x 24" two row radiator with 3/4" openings. Its loop was T's in to the 3/4" return hose after going through the heater core. The radiator hose front to back on the U225 was all 3/4". It provided plenty of flow for additional cooling. I installed the aux radiator behind the A/C unit with no fan on the aux radiator. It dropped the coolant temps 10 degrees on average. I set mine up with a shutoff ball valve to the aux radiator loop so I could take it out of the coolant system in the winter. I don't think the U225 had the Auxiliary Coolant Pump like the one on my U300 so it might have worked even better with a pump.
The info off my valve is "Sunstand Thermostatic valve Date 97 f11, PN 553/1/09856/190
I found a good thread discussing the valve and the hydraulic system. Also, said Sunstand on it, I didn't look hard for a PN, but it [EDIT: My PUMP is weeping, not the thermostatic valve] is weeping a little around the shaft...grrrr. Anyway, it appears Monaco and others used this same hydraulic setup---so I doubt it is special to FT.
Thermostatic Valve - iRV2 Forums (http://www.irv2.com/forums/f104/thermostatic-valve-73316.html)
Also, I'd say the valve control is probably variable.
More useful good info, go to page 7: http://www.bibus.hu/fileadmin/editors/countries/bihun/product_data/sauer-danfoss/documents/sauerdanfoss_group_2_gear_pumps_catalogue_en.pdf (http://www.bibus.hu/fileadmin/editors/countries/bihun/product_data/sauer-danfoss/documents/sauerdanfoss_group_2_gear_pumps_catalogue_en.pdf)
Also, part number break down. I haven't looked closely at my motors yet to see if I can find PN info.
This is probably the best thread and system description: Side Radiator wax valve replacement - iRV2 Forums (http://www.irv2.com/forums/f115/side-radiator-wax-valve-replacement-148331.html)
I was going to do this test or Barry was, but this guy already seems to have done it.
"The little red valve on the test gage is very sensitive because the flow to the control circuit is very small, just a slight movement and you get a big fan speed change.
Basically just moving the valve from open to closed causes the fans to run very slow (open) to very fast (closed) with a linier operations between open and closed. The fans work great."
And here's something interesting...these guys are selling the wax valve to replace the electronic control valve:
Source Engineering Inc | Custom RV Chassis | Eugene, OR (http://sourcerv.com/conversion)
"All Monaco, Western RV, Bluebird,
Foretravel, Country Coach and others
If you have a coach with the Saurer-Danfoss
hydraulic fan drive and have experienced failures
related to the electronic control unit known as the
"FDCA" we have a economical answer to the problem.
When these controllers fail the fan typically will
go to full speed and will not modulate this will create
several undesirable effects."
I don't think FT engineered this system in house....just like many components on our coaches, they bought them from another company that figured it out. Like, the doors, the leveling system, the toilet, the tanks, etc etc.
I reading somewhere that the Italian motor maker is Casappa
What years have what system?
Krush ---- I'm guessing that your hydraulic fluid is 15w40 based on earlier info on the forum. If not and your fan hydraulics are part of the steering system which uses power steering fluid, You may want to try using a power steering stop leak to condition that shaft seal. I was having some leakage (a half dozen drops a day) so I used two small bottles of LUCUS power steering stop leak and now after several thousand miles of running, It has stopped leaking. Have a great day ---- Fritz
Fritz, on my coach the fan and powersteering share the same pump/fluid. Instructions say 15w40 motor oil. But I'm thinking about switching to hydrualic fluid.
Last bit of information from another forum: "It [hydraulic fan motor] has the Sauer danfoss part no. on it but is now made by Dynamatic"
This or Casappa is the motor?!!? I guess lol.....
EDIT: OK, here is the mother of all hydraulic fan/pump/system information. I didn't dig through it all, but it has specs for most of the pumps, valves and motors.
http://www.mbh.com.br/pdf/Lit/520L0824_Fan%20Drive%20Control%20ME_TI_Nov-2005_Rev%201.pdf (http://www.mbh.com.br/pdf/Lit/520L0824_Fan%20Drive%20Control%20ME_TI_Nov-2005_Rev%201.pdf)
It appears the system is the same, it's just that company names have changed over the years due to buying/selling.
According to this PDF from Sheppard, it is ok to use Exxon and Valvoline AW 32 hydraulic oil.....realistically, any AW 32 hydraulic oil. I think using hydraulic oil in the system may give better life to the pump and motors.
http://www.rhsheppard.com/service/Approved_Fluid_List.pdf (http://www.rhsheppard.com/service/Approved_Fluid_List.pdf)
@krush Thanks for the Sauer Danfoss document. There is a lot of good info in there. It's given me some ideas!
see ya
ken
I had been looking for a document for the sauer danfoss manual last week, but didn't find one so I took every thing apart to find out
how it works so I could trouble shoot it. I will keep the document.
Remember, it's flow, not pressure!