belt question on 89 4.0

I just purcahsed an 89 xj 4.0. I noticed the belt was kinda frayed along one edge. I picked one up and put it on. As soon as I start the engine the belt will "walk" over one grove on the harmonic balancer towards the engine. I know the water pump has been replaced, but it looks like it may not line up with the rest of the pulleys.
Could the belt do this if there is not enough tension on the belt?
Second if the water pump pulley is not lined up what can be done to correct it? There appears to be a spacer on the outside of the water pump pulley, is this correct or does it go between the pump and the pulley?

Thanks for anyones input.
Scott

I am betting your harmonic balancer is disintegrating. The outer ring of the balancer is bonded to it's hub with a rubber donut type thing. The donut fails with age/heat/oil, and then the outer ring moves inward or outward, resulting in the crank pulley not being in the same plane as the rest of the pulleys for the belt.

Put on a new balancer, and the problem will go away. If you DON'T do this, it's possible for the balancer ring to move rearward, towards the engine, and then grind a hole through the timing chain cover on the front of the engine. That's a "bad thing" as we like to say.

I noticed on the balancer that there is a rubber piece starting to stick out from the front. I'm guessing this sort of isolater between the two pieces of the balancer which I think would indicate that its toast, as you mentioned above.
Thanks for the info!

That rubber piece is indeed the culprit. It's toast, and if you don't eat into the timing cover you're at least at high risk for losing the serp belt...

Were is a good place to get another one? I mean besides the dealer.

Yes, you have a bad harmonic balancer/crankshaft damper on your 89 XJ. Mine on my 88 XJ let go at 115,000 miles. I had the guys tell me on here 4 years ago to fix it today, do not wait till tomorrow.

After reading this post take the XJ to a shop your trust and have it replaced OR do it yourself in the driveway at home. I don't care if it your only vehicle it needs to be repaired today.

You may want to do a search on hamonic balancer replacement, I recall Chrysler modified the component and you need to change the timing cover seal and get a new crank shaft bolt since the one you have is too short to pull on the new dramper. I recall Eagle saying you can still get the damper from Crown automotive which is idential to the one you have failing and uses the same crankshaft bolt. I seem to recall if you use the "new design" dealer part you will spend 4 hours doing a 1 hours job since you will be changing stuff that would of been undistrurbed if you use the crown component.

Also when you install a new belt make sure you tension it correctly. For my 88 XJ the belt tension is 180-200 lbs for a new belt and 140-160 lbs with a used belt. Napa sells a very nice tool called the Kricket II, it measured belt tension and is less thatn $20, $12 pops into my head. I got the model which goes to 300 lbs since the model below that did not go to 200 lbs. If you need the NAPA part number let me know. Also replace the idle pulley next to the air conditioner compressor, mine was rough 2 years ago when I changed the water pump. I paid $10 at Advance Auto parts and it was a Dayco pulley.

I also found the Goodyear Gatorback belt works very well and cuts down on belt noise, got taht a Autozone. I change my belts and hoses every 4 years regardless of mileage and in the past 2 weeks installed new radiator hoses and fan belt. The kricket II was awsome tensioning up that new belt. I had used the tool on my used belt but this was my first time using it on the new belt. I got it to the tension to the published value, no guessing.

martin said:

.. Napa sells a very nice tool called the Kricket II, it measured belt tension and is less thatn $20, $12 pops into my head. I got the model which goes to 300 lbs since the model below that did not go to 200 lbs. If you need the NAPA part number let me know.

Click to expand...

Martin, my local NAPA looked at me like I was speaking French when I asked for a Kricket II. Can you please provide the part number, if possible. (You can PM me if you prefer.)

Front Label

NAPA KRIKIT II V-BELT TENSION GAUGE
KR2 bar code 0 29769 35216 8

end label

KR2
7401-0102
1 EACH

It has a range of 100-300 lbs.

Please publish that part number here. I would like it too.

Thanks for all the helpful info guys. I'm ordering a new balancer tomorrow.