skidoo_j Posted June 3, 2012 Share Posted June 3, 2012 Recently I noticed a squealing sound comming from my engine compartment at 2200-3000 rpm. I opened the hood for investigation and found that when in that rpm range the serpentine belt walks forward on the clutch fan pulley and squeals. When watching the belt it appears in perfect alignment at sub 1k rpm. none of the others appear to be spinning akwardly. Both the idler pulley and the a/c pulley are new. I recently replaced the fan clutch so i rechecked the bolts and they're tight, I did use the zj fan clutch that is bigger. I'm trying to figure out what could be causing the walk. Belt tension seems fine, I can turn it to 90 degree with out having to wrench on it. Ideas or thoughts greatly appreciated. Link to comment Share on other sites More sharing options...
Jeep Driver Posted June 3, 2012 Share Posted June 3, 2012 Harmonic balancer needs to be replaced. Link to comment Share on other sites More sharing options...
skidoo_j Posted June 3, 2012 Author Share Posted June 3, 2012 Harmonic balancer needs to be replaced. That was my fear, but it doesnt have any odd motor vibes. And the harmonic balancer looks like it's spinning true. I'm thinking maybe the fan clutch pulley is off or just the extra pull the working fan clutch has put on it is causing the belt to move. Link to comment Share on other sites More sharing options...
skidoo_j Posted June 5, 2012 Author Share Posted June 5, 2012 I replaced the harmonic dampener. The old one had some of the rubber coming out of the ring, however it did not solve my problem. When under hard acceleration or at certain rpm the serp belt walks to the front of the vehicle on the clutch fan pulley and squeals. It's loud... I held some sand paper on the pulley from the underside to clean up that lip encase there was a bit of rust accumulation, I held wax on the edge of the belt that rubs.. I cannot see any movement in any of the pulleys when the belt travels only the belt appears to shift, and only on that one pulley. between the idler and the power steering you can see some vertical vibes or waves in the belt, but no front to back movements. I watched the belt down the a/c pulley to alternator and see no shift in any direction. watching the belt from the dampener to the water pump there's no shifts in the belt. So i'm wondering if that pulley that drives the fan clutch could be bad, or the bearing that it spins on. problem is there is no part number through any parts store listings. So does it never go bad??? Could the belt be bad? Too tight, too loose? age of parts: water pump is about a year and half old a/c pulley a month idler is 2 years old dampener new (today) belt 3 yrs atleast clutch fan a month (zj) Link to comment Share on other sites More sharing options...
Jeep Driver Posted June 5, 2012 Share Posted June 5, 2012 I had a belt once that was oil soaked that squealed. I replaced that WP and idler and AC mount/fan pulley bearing and still had the squeal. Replaced the belt and solved the problem. Make the belt squeal then mist a little water on it and see if the squeal goes away. Link to comment Share on other sites More sharing options...
DREDnot Posted June 5, 2012 Share Posted June 5, 2012 Belt tension seems fine, I can turn it to 90 degree with out having to wrench on it. Is this some sort of test of belt tension? That sounds a little loose to me. I would replace the belt and tighten it a little tighter than you normally do. The correct tightening procedure uses a tool to measure tension. Since nobody has one, I usually hold a straight edge across the pulleys and deflect the belt in the middle and tighten till you can't deflect it more than a half an inch. Link to comment Share on other sites More sharing options...
Jeep Driver Posted June 5, 2012 Share Posted June 5, 2012 Yeah I go 3/8 or so. Some folks need the tool but then some folks need a lot of things........lol Link to comment Share on other sites More sharing options...
skidoo_j Posted June 8, 2012 Author Share Posted June 8, 2012 Well i replaced the serp belt with a Dayco. I now only get a belt squeal with a very hard throttle acceleration. If it comes back as bad as it was i'm going to pull that pulley and spin it on the lathe until it's flat. Link to comment Share on other sites More sharing options...
skidoo_j Posted July 9, 2012 Author Share Posted July 9, 2012 Well i replaced the serp belt with a Dayco. I now only get a belt squeal with a very hard throttle acceleration. If it comes back as bad as it was i'm going to pull that pulley and spin it on the lathe until it's flat. alright damn thing squeals all the time at 3k rpm and at hard accel. I'm 99.9% sure the belt is are correct tension less than 1/2" deflection.... from power steering to idler. I'm wondering if the zj fan clutch is causing this. I never had a squeal prior to installing it. i'm waiting for the truck to cool down, then i'm going to go remove the fan/ clutch and just bolt the pulley straight on. I figure if it doesn't squeal then it's because the clutch is not releasing due to bad or the fact it's "heavy duty" and won't disengage due to the lighter fan. if it still squeals i'm thinking alternator maybe going? or the bearing the clutch fan runs on. the harmonic balancer is brand new and so is the belt. I welcome ideas and thoughts.... Link to comment Share on other sites More sharing options...
skidoo_j Posted July 9, 2012 Author Share Posted July 9, 2012 with the fan and clutch removed and only that pulley attached the belt does not walk forward or squeak. I do however notice a pretty good forward tapper on the belt running surface. so I'm not sure if it's the fan clutch or a bad/worn pulley surface. and some play in the bearings on the mounting shaft. the fan drive pulley is part number 53010309AB it's $90 from the dealer. Crown makes one but I haven't found their price yet, I'll have to call quadratec or rusty's tomorrow to see what price they can get it for. The bracket that contains the bearing for the fan is 260 dollars. I'm going to pull it and see if i can figure out how to press out the bearing and replace it. i'm also debating on returning the ZJ fan and just getting a new xj fan. Link to comment Share on other sites More sharing options...
DREDnot Posted July 10, 2012 Share Posted July 10, 2012 with the fan and clutch removed and only that pulley attached the belt does not walk forward or squeak.... i'm also debating on returning the ZJ fan and just getting a new xj fan. This...and a new pulley. I think that should cure it. It seems like you engine was able to rev past the fan that was locked up tighter than design. The belt would scrawl forward to try shortcut past the slower pulley. Link to comment Share on other sites More sharing options...
skidoo_j Posted July 10, 2012 Author Share Posted July 10, 2012 with the fan and clutch removed and only that pulley attached the belt does not walk forward or squeak.... i'm also debating on returning the ZJ fan and just getting a new xj fan. This...and a new pulley. I think that should cure it. It seems like you engine was able to rev past the fan that was locked up tighter than design. The belt would scrawl forward to try shortcut past the slower pulley. The new pulley will cost $20 to my local crown dealer. Hopefully i get it this week or early next and of course that it is infact the correct part. 53010309AB. Now i'm headed to see if i can press out the bearings in that bracket that the fan spins on to replace them Link to comment Share on other sites More sharing options...
skidoo_j Posted July 10, 2012 Author Share Posted July 10, 2012 the bearing in the bracket that holds the clutch fan is a water pump bearing. I picked one up at my local bearing supply (no-joke it's all they sell) for 18. I had to cut the shafts to length using a cut off saw as the steel was very very hard. Then pressed it all back together. lesson learned when pulling off the mounting surface be sure to press it out square. and back on square. I'm not sure if it was always this out of true, but once the mounting surface was pressed back on it has a pretty good walk, so the bearing got repressed out with the mounting surface still attached (after several attempt with a BFH to square it) and then turn in the lathe so my mounting surface is true to the shaft. Shaft Diameter : .6267" Bearing Diameter: 1.1811" Total Length: 4.56" Short Side (fan side): 1.10" Long Side (goes up inside bracket not all to important on this length): 1.930" Looks like napa BRG 885154B would work, it wouldnt have the shaft that goes back inside the bracket, but if you can't source it else where, It looks like it would still need a bit of shortening. but 12 dollars beat 120 for the bracket with the bearing (that's the only way my dealership would sell me). Also replaced the drive pulley with part number 53010309AB by crown as my old one appeared to have a tapper on it that may have also led to the walking of the belt to cause the squeal. Link to comment Share on other sites More sharing options...
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