| Author | Message | ||
| jim barker
Rating: N/A |
How do I tell if my hydrolic clutch fan is working properly? Is there a way to lock it up to see if the engine temp goes down? I have a 6V92T with V730. New radiator several years ago but has always had a heat problem as long as I've had the bus. If outside temp is over 85 I have to drive below 60 to keep the engine temp below 200. No black smoke except during take off. I added scoops to the rad air intake several years ago with no change so I removed them. I don't have a rock guard across the rear of the bus. Thanks for any info. | ||
| Brian Brown (Blue_velvet)
Rating: N/A |
What make/ model is your bus? Since it's a V tranny, I'm assuming it's a GMC of some sort (but could be a transit of other makes). Firstly, make sure your rad shroud is in good shape. Mine was missing from my '06 when I bought it earlier this year. I had problems with running hot even on the flats when the ambient temps got over 85. Then. my HVAC buddy made me a new shroud out of 20ga sheet metal and now it runs nice and cool. I just got back from a 3000 mile trip out west and she ran cool climbing, and even through triple digit desert heat never got over 190 while running at 75mph. Now, if your bus originally didn't have the auto tranny, you're adding some significant heat there that a stock-sized rad will have trouble coping with. Mine's a 4-speed Spicer, so I can't help much there. The GMC Yahoo forum has had some interesting posts lately about dealing with slushbox heat. Maybe I can dig up something from the archives. I believe that the DD book gives some info on the fan clutch maint. and testing, but I don't have it handy. Post a bit more info and the kind folks here will surely try to help you out. Cheers, bb PD4106-1175 | ||
| carl gullett
Rating: N/A |
JIM for whot it worth i have a 6v92 at alison 5 spead it was runing 200 at least and i found an oil cooler of a login truck says hayden industrials products on it 5/8 pip with cooler fens on it 1-5 inch thick 8 wid 14 inchlong temp now runs 190 with temp above 100 around yuma its working fore me try truck wrecking yards | ||
| jim barker
Rating: N/A |
The bus is a Western Flyer. It was a transit and came with the V730 from the factory. The radiator shroud is in good shape. I want to be sure that the fan clutch is working properly before I add an oil cooler. I don't have a DD manual but I guess I'll have to spend the $$ and get one. Has anyone heard of a place that sells a cd of the manual? Thanks, Jim | ||
| Brian Brown (Blue_velvet)
Rating: N/A |
Jim, look on eBay for a DD manual. They're fairly common there and you shouldn't have to spend too much on one. I got one for about $30 that way. You'll likely want a paper copy to keep in the bus w/o having to fire up a PC to read it. That said, www.coachinfo.com will sell you a CD DD manual, but they're pretty pricey. With your V730 being on a factory bus, something is likely amiss if you're running hot. However, being a transit it might not have been engineered to run at highway speeds for extended periods. Have any idea what kind of rpms it's pulling at speed? Just curious. Also, after you've heated it up, have you ever pulled over and checked to see if the fan is running full-bore? You might also invest in an IR gun to check temps at the upper and lower rad, and also at the fan clutch to assist your troubleshooting. Works on exhaust, cyl. heads, brakes, wheel bearings, etc. also. HTH, bb | ||
| Sammy (Sammy)
Rating: N/A |
Jim, I'm not familiar with a Western Flyer transit coach cooling fan set up. What type of fan clutch does it have that locks up - air operated, or oil driven-like a torque converter? We call the oil driven one a fan "torus".Both are activated by engine coolant temperature valves.I have converted a few RTS transits with the fan torus to a later style belt driven cooling fan. It's a great swap.No more leaks or trouble.Got the parts from a donor engine. Send an e-mail if you have any questions.Best of luck with your troubleshooting. | ||
| jim barker Rating: N/A |
When I bought the bus I had the rear end changed from 5.38 to 4.11 so I could have some highway speed when I drove it home from Canada. It only went 62 mph before the change and now will go about 78. I don't have a tach so I don't know rpm. The previous owner said it didn't overheat before the gear change but you know how that goes. The fan is not air controlled so it must be oil. I looked at the fan while I was driving but it looked like it was running the same as when cold but I don't know if I could tell the diff. I'll watch ebay for a manual. someone had told me that a paper one was $150 so I haven't looked. I used to know how to spell hydraulic before I got old. Thanks for the replys. | ||
| Brian Brown (Blue_velvet)
Rating: N/A |
Jim, if it's indeed an oil torus, and functioning properly, it should barely rotate at all when cold... and almost suck you against the radiator when hot. So you should be able to tell a difference if it's working as it should. Now, if it's locked up some how, your cold weather performance could suffer by not letting the engine heat up. But if it's somehow not turning at the proper rpm, or slipping, that could certainly lead to your troubles. And how'd you look at the fan while you were driving??  With your rear end swap you shouldn't be stressing the engine at reasonable highway speeds with a normal functioning cooling system. Something is indeed wrong... unless your gauge is off. A basic IR gun or a new digital gauge with sender (either one is less than $50 on ePlace) would verify this. Also, make sure your oil is at the line on the dipstick. The oil torus locks up oil inside it and needs all of the pan capacity for proper cooling. Low oil will make it run hotter because there's less oil and pressure for the torus and for the oil cooler(s). bb | ||
| Tom Caffrey (Pvcces)
Rating: N/A |
Brian, I don't think lack of pressure would be the reason for poor cooling as much as the oil pickup drawing air. This would result in lower pressure but lower pressure would only be an effect of air getting into the pickup. I imagine air in the torus would increase its slippage, slowing the fan. I agreee that the oil level should not get very low. Tom Caffrey PD4106-2576 Suncatcher | ||
| jim barker Rating: N/A |
Brian, I meant that I looked at the fan rotation when I stopped driving and the engine was hot but I think you figured that out. I really didn't notice any big diff in the rotation speed. Does the DD manual give a parts breakdown? Maybe I should take the torus apart to see if something is wrong in it. I won't be able to drive again until Nov and it's not very warm here or where I'm going then. I went south last year at the same time and didn't have any heat problems. I think the gauge is OK because it showed about 180 on my fall trip. | ||
| Brian Brown (Blue_velvet)
Rating: N/A |
Tom, maybe you're right that oil pressure doesn't affect cooling. But I still think that the volume of oil (or lack thereof) probably would. Having less fluid for the oil cooler to cool, as well as less of what's needed for doing its job within the inner workings of the engine, the lubricant would run hotter, which would make it thinner and lead to lower pressure (right when the engine needs it more). I'm no DD expert, just an armchair speculator. And yes, I think you're right that pulling air into the torus would be bad. Thanks, bb | ||
| Brian Brown (Blue_velvet)
Rating: N/A |
DD Manual pages uploaded... Hey Jim, I uploaded some hopefully relevant pages of my DD manual for you. My scanner's being a pain, so I just took pics with my 5MP digital cam and put some compression on them so they weren't too onerous to download. http://www.archtex.com/bus/DD/ There's five pages on the torus (be sure and ignore the truck version) and two on the Fluid Control Valve. The FCV controls the flow of oil to the torus and might also need calibrating/ overhaul in your case. Be forwarned that these are from the 8v71 manual and might not be exactly the same as yours. And let me know if you can't read 'em or download 'em for some reason. Hope this helps until you get your manual, bb | ||
| jim barker Rating: N/A |
Brian, thanks for the pages. I saved them to my pc so I will have them. Jim | ||
| Doug G Rating: N/A |
Other things to consider: 1. Clean the radiator with air pressure first, then a degreaser, then water, in that order. You'll be surprised what gunk comes out. 2. Adding an air scoop may lower temps 10 deg.- many older coaches did not direct the air into the radiators well. See Fred's article and pictures on installing air scoops: http://users.cwnet.com/~thall/fredhobe6.htm | ||
| Dale L. Waller (Happycampersrus)
Rating: N/A |
Jim, I know this sounds dumb, but what type and weight oil are you using?? The wrong oil is too thin and won't spin the fan at the right rpm's. The torus also has a oil return line on the lower radiator hose to the oil pan. If you take that loose and cap both sides, then start the engine and check the rpm's. run the engine up and see what the fan does. If slow (low oil flow) you probably new to get a rebuild or do like Sammy says and change to a belt drive. The torus works like an auto trans torque converter. Nimco has the torus drives. Dale | ||
| Tom Caffrey (Pvcces)
Rating: N/A |
Dale, you misunderstand how a fluid coupling works. And the torus is not a torque converter. In a nutshell, the heavier the oil, the less efficient it is. The thinnest oil gives the best performance. I take it that you didn't make the connection when you saw that ATF is a low viscosity oil. That's why. For what it's worth. Tom Caffrey PD4106-2576 Suncatcher | ||
| Dale L. Waller (Happycampersrus)
Rating: N/A |
Darn, I guess the ones I have rebuilt must be a figment of my imagination. both halves of the torus have a "wheel of vanes" that lock up controlled by the oil quantity. more oil more lock, thin oil they slip. They work off of friction. Thinner oil will slip. | ||
| Dale L. Waller (Happycampersrus)
Rating: N/A |
Jim, The fan drive is controlled by a valve on the bottom Radiator hose, that is the oil return line. That valve is normally open as the temp goes up the valve closes. That allows the fan drive to fill up with engine oil. The engine driven side will turn the fan side, as oil fills up the drive that will create a "lock up". the excess oil in the drive drains back until the valve opens. I have never seen one use ATF? But hey I only have been a heavy equipment mechanic since 1992. Could be that modern stuff I guess P.S. Jim, to check lock up take the return line loose and cap it. Then run the engine | ||
| Tom Caffrey (Pvcces)
Rating: N/A |
Dale, they work off of inertia. The more oil volume and the faster it travels, the faster it drives the fan. At an idle, the coupling has very little force. For what it's worth. Tom Caffrey PD4106-2576 Suncatcher | ||
| Dale L. Waller (Happycampersrus)
Rating: N/A |
Well Tom, When I went to transmission and other related schools here is a little of what I learned. I didn't want to have to get into all this but, You are close to right now, quantity of oil matters as I posted, but also oil wt. First off a torque converter is a fluid coupler with only one major difference. a fluid coupler can transmit torque but not muiltiply it. A torque converter can transmit and muiltiply engine torque. That allows automatics to use less gears (another lesson another time). A torque converter uses two torus or vane wheels, But they are called an impeller or pump. the other side is the turbine or driven. On a torque converter a stator is placed between the impeller and turbine to help muiltiply torque. I can go deeper into the function if you need me to. A transit bus torus drive is just a simple fluid coupler. As I said oil enters the drive or pump side as the oil is moved it hits the vanes of the turbine or driven side and causes it to spin. This is refereed to as rotary motion. When the driven and driving torus are rotating at the same RPM's rotary flow and motion is constant, BUT if the medium of power transfer is OIL (not atf) the thinner it is LESS power is transferred unless you have absolutly no load. If you fill it with air NO transfer. If you add 5wt oil slight transfer of power. If you add 40wt. oil more transfer. If you add 90wt. even more transfer of power and so on. Inertia is the resistance an object has to a change in its state of motion. If you can't give the driven side torus enough torque to over come this resistance (example right wt. oil) the driver side torus motion is lost or wasted. I didn't want to have to give a fluid dynamics class and surely don't want to offend anyone. Trust me all Jim has to do is cap the return line and run the engine. If the fan spins equal with the engine RPM's the drive is fine and probably has a bad thermovalve on the radiator hose. I do see were I wrote friction. I was in a hurry to get to work you got me there. LOL. Dale | ||
| RJ Long (Rjlong)
Rating: N/A |
Tom & Dale - You guys are both saying the same thing, just using different language to do so. Kapiche? Jim - Chances are the culprit is the valve. The torus unit itself is very reliable. As has been suggested, make sure the engine oil level is correct and you've got straight 40wt oil in the pan. Then try Dale's suggestion of capping the valve line to see what happens. Isn't this hobby fun??? RJ PD4106-2784 Fresno CA | ||
| Tom Caffrey (Pvcces)
Rating: N/A |
I only argued the point because of the mistake on viscosity; both fliud couplings and torque converters are more efficient with thin oils. If heavier weight oil helps, it's because of leakage somewhere in the unit. RJ, I was concerned about our torus because I caught it leaking shortly after we bought our coach. There was a bit of looseness in the bearings. However, we have put many more miles on our coach and it has never leaked again. I can't feel any looseness at all anymore. I don't intend to work on it unless something else happens, but that did puzzle me some. I guess you just never know, huh? Tom Caffrey PD4106-2576 Suncatcher | ||
| Dale L. Waller (Happycampersrus)
Rating: N/A |
I only argued the point because this particular application is designed to be used with the heavy engine oil (40wt.). I didn't want Jim or anyone else confused about the "thin oil" issue seeing how they can't run ATF in a Detroit engine. Dale | ||
| jim barker Rating: N/A |
I use 30w oil. I will cap the return line and see if the fan turns faster than uncapped. Thanks guys for the info, it is just what I was looking for. Thanks to all who replied. |