jeep29891

I need the full set of specs for the hydraulic cooling fan in the 02-04 jeeps. I am looking for the specific build on them
Any help would be greatly appreciated!!

djb383

If u r referring to a radiator fan clutch, the mechanism contains a silicone type substance (not hydraulic fluid/oil) and it responds to heated air coming off the radiator. Hotter temps cause the fan to engage more (pulling more air thru the rad when needed) and cooler temps allow the fan to engage less (freewheel more) for less noise and more power to the wheels (better fuel economy). Go to a auto parts store and ask to see a new one.

Lowrange2

He's referring to the Hydraulic fan set-up on a WJ.

Like I said before... take all that junk out and replace it with Electric fans.


To answer your question I doubt you're going to find rebuild specs on that contraption online.

Lowrange2

Electric conversion is simple...

Replace Power steering pump with 99-00 Pump, remove hydraulic crap, install dual fan set-up of your choice.

jeep29891

What if it were as simple as replacing the ball bearings with the same weight in steel putty?

jeep29891

I have a theory that the bearings are just there for weight to provide the pump with resistance. But they keep coming out. If I could replace them with something of equal weight that won't come loose, that would save a lot of people future grief, and the $1100 expense of replacement!!

Lowrange2

Or if you'd like to stay with the hydro fan go check in the pull-part yards.

At the PAP a fan is a fan. Probably 30 bucks for the whole thing.

Lowrange2

I don't know what you're talking about. For some reason I don't think it needs weight. I read that the solenoid is what usually goes out...

jeep29891

Lowrange, I'm not sure if it does, but the bearings are stationary. They are not designed to move or roll in any way. The fan itself has 2 rows of bearings on the front, and 2 more on the back. All of these are mounted in a cradle design in the fan, so each one has its own little cubbie to sit in. As far as the fan itself, it is both an engineering marvel, and a nightmare at the same time. When we first got the Jeep, and the fan was on high speed, you could feel the air flow underneath it at the back of the Jeep while the temp outside was 114 degrees. The temp gauge never moved above half way, and the engine didn't strain or bog down in any way. I own a small car dealership, and I frequently go to the auctions. I pull a 20 ft trailer with 2 cars on it with the Jeep because it gets way better mpg than my f250, and still no strain on the cooling system. So please understand my new found infatuation with this fan working correctly. As time went by, the bearings started to disappear, now the fan doesn't work correctly. It kicks into high speed for about 10 seconds, then goes back into the roughly 500 rpm idle mode, and the Jeep gets hot. I started to do some research on hydraulics, and in order for it to measure pressure, there needs to be some resistance. My theory is that the fan blade setup itself is too lite to show the pump the proper resistance. I think the engineers put the ball bearings in the fan just to add a few pounds to it purely to make the pump feel the extra resistance so it wouldn't send the ecm a signal saying we are at max speed. This is the reason I don't just want to scrap this fan, and install an electric. I would really rather get this fan working. If it is necessary for me to shell out the $1100 for a new one, I will do it. But if thru my research, it not only benefits me, but others as well can use this info and save hundreds or even into the thousands, that's a pretty good cause. So if you know someone that has some experience with this fan, have them post and see if we can use their info to help others.

jeep29891

Lowrange, with all of my previous post being said, this Jeep is also my wife's daily driver. Of all the cars we had on the lot at the time, she picked this one. We have in no way modded this thing, and we refuse to do so. For the most part, I have been banned from driving it!! We raced an Infinity G35, and beat it in the 1/4(that's why i'm not allowed to drive it). I love this car!! But I really want it to work correctly. There is nothing sexier than a sexy woman driving a sexy car!!