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Fan/Idler pulley/AC/Alt bracket help!

Hello All!
I'd use the search, but I'm not even sure of the correct nomenclature for the part in question...
On my 1999 4.0 manual XJ Sport, it seem that the bearing on the fan pulley has taken a dump. I was alerted to this by the fan ever so slightly kissing the crank pulley, not enough to do damage but the sound sure got my attention! Luckily, this occurred at home as I was driving to the front gate. Upon opening the hood, I saw that the belt had crept about 1/4 of the way off the idler pulley, confirming that the bearing had failed. The cast bracket that supports the pulley and accessory's seems to be unavailable... Is that the case or am I missing something? Can anyone point me to a source for this part? New or used. If the part is indeed out of production, has any enterprising shop figured out a way to repair the bearing on the factory piece? Also, if you could direct me to any useful threads on the subject (I'm sure that this has been covered before), it would save me some much needed time and I'd be very grateful! Many thanks!
 
Update: Time for a electric fan?

Update:
I was able to get the Omix-Ada 17104.83 bearing that he used in the YouTube video. Quadratec was out of stock, but I was able to get it from Amazon. Unfortunately, the new bearing was as sloppy as the one I pressed out. PIA, but with Prime, I was able to get a replacement in a few days. Bearing number two was just as bad as the one I sent back!! I know that there are a bunch of e-fan conversions out there, but is anyone removing the idler/fan pulley and running a shorter belt? On another note, has anyone else noticed that quality control has he continued to get worse and worse over the years? I I go out of my way to buy American-made, but unfortunately, the majority of things are being made overseas. This is a problem, but it is what it is... I would hope that with Stateside quality control it wouldn't be so bad. But it is, and it seems to me that businesses just take it in stride and you can return just about anything these days no questions asked...
 
Omix-Ada is notoriously bad when it comes to quality. Crown as well.

Somewhere out there is an SKF or comparable p/n for this bearing. Check with Motion Industries. That was the source folks were using.
 
Omix-Ada is notoriously bad when it comes to quality. Crown as well.

Somewhere out there is an SKF or comparable p/n for this bearing. Check with Motion Industries. That was the source folks were using.

Thanks friend! I'll get on the phone with motion on Monday. The e-fan/short belt conversion is still looking attractive...
 
How does the harmonic balancer (crank pulley) look? Are the outer ring and inner hub still lined up? If the outer portion has started to separate and move forward, that will cause the belt to start drifting forward as well. The balancer going bad is more common than the idler pulley bearing.
 
How does the harmonic balancer (crank pulley) look? Are the outer ring and inner hub still lined up? If the outer portion has started to separate and move forward, that will cause the belt to start drifting forward as well. The balancer going bad is more common than the idler pulley bearing.

Thanks for the reply!
I haven't checked it, but I will go look. Is it obvious from a casual inspection? I didn't notice anything when I was pulling the fan off but, I've never had occasion to remove the crank pulley, so I'm not familiar with the assembly... Would it be possible for you to point me to image of the assembly and how its comes apart? I'll go out to the shop and look right now, stand by...
 
It should be fairly obvious. There is an outer portion, a thin rubber layer and then the inner hub. They should all be even. The rubber can protrude a bit so long as it's doesn't look like it's falling out, but the inner and outer faces should be even.
 
The outer ring on this one hasn't wander too far yet, but it's obviously failed with the rubber falling out.

287234d1461420543t-1990-harmonic-balancer-belt-s-harmonic-balancer-failure.jpg
 
I had no idea there were two parts to the crank pulley, I think that with your help, I've found the problem! I can see that the part that the serpentine belt contacts has moved forward and I can see some of the rubber delaminating and separating on the back side close to the engine block. What's the best/ easiest way to remove the crank pulley? Also, do you know of a source for a quality new harmonic balancer/pulley? I feel pretty lame for not doing a better diagnosis of the original situation...
 
The outer ring on this one hasn't wander too far yet, but it's obviously failed with the rubber falling out.

287234d1461420543t-1990-harmonic-balancer-belt-s-harmonic-balancer-failure.jpg

Thanks! Would you by chance know the part number?
 
The Dorman balancer is probably fine. I have yet to find that anyone makes a "better" balancer for the 4.0L. They all seem to be the same chinesium castings. The important part of replacing the balancer is that you are replacing the rotting rubber.

For the harmonic balancer you want both a removal tool and an install tool. Both can probably be "rented" from the auto parts store ("rented" meaning purchase a loaner tool and then return it for a full refund).

The harmonic balancer goes on the crank with an interference fit. Do not think you are going to hammer it on. That is not healthy for a cast iron crank. Also do not think you are going to draw it on with the factory balancer bolt. Cast iron threads are not that strong. The factory balancer bolt may work for the last quarter inch or so of the installation, but not the first half inch.

Also note that when you install the new balancer you should put a small dab of RTV silicon on the crank key to seal that area from leaking oil.

One other detail, if you have an automatic you may need to come up with a way to hold the engine to keep it from turning. If you have the serpentine belt installed you may be able to do something like hold the alternator still with one ratched while turning the crank with another. Or you may need to remove the access panel for the flywheel bolts and use a prybar or large screwdriver to hold the flywheel. That tends to require a second person.

Final torque on the dampener bolt is 80 ft/lbs.
 
The Dorman balancer is probably fine. I have yet to find that anyone makes a "better" balancer for the 4.0L. They all seem to be the same chinesium castings. The important part of replacing the balancer is that you are replacing the rotting rubber.

For the harmonic balancer you want both a removal tool and an install tool. Both can probably be "rented" from the auto parts store ("rented" meaning purchase a loaner tool and then return it for a full refund).

The harmonic balancer goes on the crank with an interference fit. Do not think you are going to hammer it on. That is not healthy for a cast iron crank. Also do not think you are going to draw it on with the factory balancer bolt. Cast iron threads are not that strong. The factory balancer bolt may work for the last quarter inch or so of the installation, but not the first half inch.

Also note that when you install the new balancer you should put a small dab of RTV silicon on the crank key to seal that area from leaking oil.

One other detail, if you have an automatic you may need to come up with a way to hold the engine to keep it from turning. If you have the serpentine belt installed you may be able to do something like hold the alternator still with one ratched while turning the crank with another. Or you may need to remove the access panel for the flywheel bolts and use a prybar or large screwdriver to hold the flywheel. That tends to require a second person.

Final torque on the dampener bolt is 80 ft/lbs.

Many thanks!
Manual transmission. No helper available, any tricks for doing it solo? If I use a "Y" style puller, is it possible to do it without removing the grill, radiator and condenser?
 
Manual trans, just put it in 5th gear with the parking brake on. You can rent/borrow a puller from Autozone and others. The main bolt on some of the pullers are pretty long and will hit the radiator. The last few I've done, I found a shorter bolt for the puller.

For reinstalling, do not use the original bolt to pull it on. It's too short and only grabs a few threads at first and you will rip those first few threads out. Instead, get a longer bolt, some washers and a nut. Run the nut and washers onto the bolt, thread that in as far as you can, then turn the nut to push the balancer back on.
 
I took the front bumper off my xj to remove the balancer I got my harmonic balancer at Napa reboxed Dorman product I used a longer bolt and some washers to reinstall balancer.
 
Thanks gentlemen! Is it possible to do w/o pulling grill,rad,etc.?
 
The harmonic balancer is low on the engine and low on the chassis. I had no interference issues with radiator/AC condenser.
 
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