Bad squealing 4.0 I6

Ryn109 · Mar 26, 2010

Just swapped a newer 4.0 to my 92 yj and am using my old PS pump/alt, running no AC. Have brand new serpentine belt on and it's tight. I'm getting an ear piercing squeal noise from somewhere.. belt slipping on bad pulley? I replaced water pump and idle pulley still squeals super loud. Gonna try and run a different pulley on the water pump just in case its slipping on the current one. Starting to lose my patience with this

please any input will help, thank you.

zukkev · Mar 26, 2010

Just when you think the belt is tight, tighten it more...But first, Make double sure the routing is correct also...And do all the pulleys line up properly with each other? Aannnnd, last but not least, make sure the crank damper on the new motor isn't coming apart, which will cause the belt to be misaligned and squeal like a stuck pig...

Ryn109 · Mar 26, 2010

zukkev said:
Just when you think the belt is tight, tighten it more...But first, Make double sure the routing is correct also...And do all the pulleys line up properly with each other? Aannnnd, last but not least, make sure the crank damper on the new motor isn't coming apart, which will cause the belt to be misaligned and squeal like a stuck pig...

All the pulleys seem to line up with each other. The crank damper seems tight? I don't really know how to check if it's bad? Wouldn't of thought getting serp belt on and not squeaking would be the hardest and most frustrating part of the swap FML.
Using this exact routing.

zukkev · Mar 26, 2010

On the crank damper---there's the inner hub, and the outer pulley part, and in between is rubber, the rubber softens, and causes the pulley part to 'walk' outward if it's bad, you'll see it and understand what I'm tryin' to explain...
As for routing, something's missing...there should be an idler pulley and bracket that bolts to where the A/C comp would bolt...the belt should go from the little idler near the stat housing up to the A/c idler, then down to the Alternator, up to the pulley where the fan clutch bolts to (that pulley should be a smooth pulley, not grooved), then down to the crank.....The way it's currently routed doesn't wrap the Alt pulley enough, and will squeal relentlessly!!! Make sense???

bigdog165511 · Mar 26, 2010

It's a heep thang:stirpot:

Ryn109 · Mar 27, 2010

zukkev said:
On the crank damper---there's the inner hub, and the outer pulley part, and in between is rubber, the rubber softens, and causes the pulley part to 'walk' outward if it's bad, you'll see it and understand what I'm tryin' to explain...
As for routing, something's missing...there should be an idler pulley and bracket that bolts to where the A/C comp would bolt...the belt should go from the little idler near the stat housing up to the A/c idler, then down to the Alternator, up to the pulley where the fan clutch bolts to (that pulley should be a smooth pulley, not grooved), then down to the crank.....The way it's currently routed doesn't wrap the Alt pulley enough, and will squeal relentlessly!!! Make sense???

Inspected my crank damper and saw where some of the rubber has eroded and appeared to be "walking" to one side so decided to pull it and throw a new one in and no more ear piercing squeal! :awesomework: And for the routing, I lied. It's not quite exact to that. That picture is how my newer motor was set up, for an offset fan with that ac bracket. I bolted up my older ac bracket off my wrangler motor where the altenator bolts up higher on it and has an idle pulley. I'm just glad it all works and no leaks or loud squeals! Thanks zukkev :beer: