Bought a used JD9300 tractor with 1600 hours. The viscous fan drive would engage most of the time when needed but sometimes the tractor would heat up into the yellow zone and would have to idle down to let it cool, then the drive would usually engage again and away we would go. Called local dealer to order one. About 1300 dollars. We were planting and needed it so ordered it. Rained 3 inches last night and now with the tractor in the shop we removed the drive, new one should be in tomorrow. Drive has "Eaton" stamped on it and a part number. Something tells me when we call around to truck dealers tomorrow 1300 dollars is going to seem very high.

Does anyone have a special source for these drives? Too late for this tractor to save money but we have 3 other 9000 series that this will no doubt happen again in the future. Put one on at the dealer on the 9200 this winter and I think it was about $600. 9200 has narrower hood and I assume narrower radiator, fan and smaller drive. $1300 seemed pricey to me.

John

I had trouble with my John Deere 9170? (don't remember the number, but it was the Deere with the Cummins in it) viscous fan drive.  When I found what they cost, I made some brackets of strap metal to lock out the drive.  I was told that all other JD engines had a lock out kit, except for the Cummins.  Figured if all others could do it, so could I have success.

I had lots of fan belt problems after that, and those flat belts are not easy to change, plus they are expensive.

I finally bit the bullet and bought a new viscous clutch, solved my problems.  I decided the expense of the clutch was much cheaper than all the down time and hot tractor going down when I was really busy at planting time.

Sorry, can't answer your question about a cheaper source, I tried truck repair places, was told that was cheaper, but they couldn't assure me that their clutch would work in an ag situation, and if it didn't work, the problems would be worse than just buying JD's expensive clutch that was designed for that purpose.

Some things are easy to save money on, some you just have to pay the price.

If the tractor engine had a lock-out kit available through JD parts, that would be the best solution.  I was told there would be a little more fuel used without the viscous clutch, and perhaps a bit of a power loss.

Thanks for the info but in this case I am pretty sure it is the drive. When the engine heats up I can idle down, go outside the tractor, hear the fan start to take hold and speed up the fan, then the engine will cool right down, even if I go right back to work. As long as I hear the fan kick in while under a heavy load, things stay cool. If I can't hear the fan kick in, it gets hot. Sometimes it works perfectly for maybe an hour before the fan fails to kick in.

I also had a 4450 that had the temp sender go out like you describe.

Yes, Ag Talk is a great place. Thanks to David for starting it, the volunteers that help him maintain it, and those who donate dollars as needed to keep it in top form. It truly is a real asset. Not to mention fun!

John

Here is an interesting article on the fuel savings in over the road trucks using direct drive fans, viscous fans and on/off fan drives.

Fuel savings were significant even at cheaper Diesel prices. On/off were the best by far, at least for truck service.

John

I noticed the bi-metallic strip and came to the assumption it rotated an internal valve to close off or open up orifices to either lock up the torque converter more or let it freewheel.

I think maybe the problem might be more like there is a lack of fluid, like some of it has leaked out over time. I see no oil residue on the drive but the previous owner I think pressure washed things pretty often. One other poster suggested drilling a hole and replacing lost fluid and that would probably work. Thing of it is, I really do not want to see the fan go through the radiator and the bearings on this unit are showing a little side to side play.

The reason I think it is lack of fluid is when it is working it works fine. Then all of the sudden it will just not engage. Idle the engine down and wait a little bit and can hear the drive slowly pick up fan speed and then I can go back to work and the fan will be running full (or thereabouts) speed. I think by slowing the engine down, it lets the limited fluid left to seek where ever it needs to be to work. That's my theory anyway.

All this is a moot point for this tractor anyway. I already ordered the drive and it may be installed by now (been terribly sic today and didn't go into the shop). What I would like is to find an internet site or a big truck parts outlet that could cross reference the Eaton number cast into the drive housing and find them about half price of going through Deere. With bearing failure causing major radiator damage and down time probably would never modify an old one unless for a short time to get by while waiting on parts to arrive. 

Thanks for all the ideas.

John 

I think that is the problem with this one, loss of oil. I think there is just barely enough oil to work most of the time. I think this is why when I idle the engine down in a half minute or so can hear the fan start to spool up, then it is good to go for a while.

Problem is the bearings were showing a little looseness anyway and do not want to risk bearing failure. Radiator I'm sure cost more than the fan drive. The adding oil trick might be a good alternative if for some reason parts were back ordered.

Really would just like to find a source other than Deere. Usually a person can take the highest available retail price he can find from an auto parts store, double it, and that is about where Deere is. Based on that, this $1300 drive probably ought to sell for about $600.

john

I suspect you are right.

One thing I hate about the on/off fan clutches on trucks is that they automatically kick on every time the ac turns on. We have instructed our drivers to shut off the AC when they pull into a field (which was not a particularly popular order during wheat harvest) because when that fan kicks on it pulls so much air it stirs up debris all over the place and plugs up the radiators.

John