Replacing harmonic ballencer on 87 4.0

[East_Nut]

Well after lots of trouble trying to find what was squealing coming from the serpantine belt on my grandsun's 4.0 was caused by a defective harminic ballencer which was rubbing against the timing chain cover. We bought a new harmonic balencer from chrysler which had a bullitin that came with it. It stated that it was neccessary to remove the timing chain cover and remove the "crank seal oil slinger". "Failure to remove the slinger may result in belt failure". The bullitin also mentioions WJ/TJ 4.0L models not the XJ. I have both Haynes and Chiltons manuals and neither tell me that I have to take off the timing chain cover. They do mention that the radiator has to be removed, but I have just about got the old balencer off (the squeal was actually caused by the balencer rubbing against the timing chain cover and was still evident when the Jeep was briefly run without the belt). What I was wondering is, why is the bullitin asking us to do this, even though its not mentioned in the service manuals. The Bullitin is from STAR PARTS TECH TIPS and was printed out at the chrysler dealership.

 

[5-90]

Well, the last two harmonic dampers I changed kept the oil slinger (I think there was a note, but I didn't read it...) and I just changed the damper and the seal under it.

I don't think I pulled the radiator again - but I did loosen the mounts so I could move it about a bit.

TIPS -
The crank nose bolt is dipped into clean engine oil and torqued to 80 pound-feet.
The inside and outside diameters of the HD snout should be coated with grease, as well as the crank snout proper (remove the Woodruff key, coat, and replace the key - that helps to keep it in place) and the seal lip should likewise be greased. Run a finger over the OD of the new damper snout to make sure there are no burrs or other defects that will kill your seal.
The damper should NOT be hammered on! The crank nose is threaded 1/2"-20, so you can get a series of bolts and washers, or just use a bit of allthread rod, a nut, and washers, to slowly install the new HD. You probably know this already, but people turning this up in a search may not, so I include it for the sake of completion...
If you change the seal (you should!) apply a light coat of RTV Black to the metal shell before you drive it in. The seal can be changed without pulling the front cover - I've done it a couple times.
MAKE DAMN SURE you have the keyways and key aligned - I've sheared off a key by not checking. Since the AMC 242 is internally balanced, it didn't cause a problem (for at least 80Kmiles...) but it's just a detail to do it right...

Can't think of anything else offhand, but I probably will later. Searching here will also help - I know I've covered this job a few times in the last couple years, and a search will likely turn up the little tips that I forgot...

5-90