lost idler pulley, now squealing w/ heater

[chedderslam]

1997 Explorer Eddie Bauer V6 SOHC, 110k miles

Driving home from work last week, lose power steering and car over heats all at once. Pull over quickly and see the serpentine belt is off. Closer inspection reveals that my idler pulley has disappeared.

Replace idler pulley, replacing belt as well. Old belt was not destroyed, just figured I would replace it while I was doing all this.

HORRIBLE squeal after starting truck. Thinking that I got a bad replacement pulley, switch it for another one. Still squeals.

Go to autozone, they test alternator and say it is bad. So I replace that, thinking that will fix the squeal. No dice.

Also tried some belt conditioner.

The squeal happens only when:

1. Starting truck, for first few seconds
2. Turing on heater, entire time heater is running

Do I need to replace my ac clutch/compressor?

 

[my98nnj]

Before you go throwing more parts into it, take the belt off and spin each pully by hand. See which one feels tight, or listen very closely to each accessory when the squeal is happening and pin point which one is making the noise.

Are you sure you got the right belt? I had replaced my belt a while back and had a minor sueal that drove me nuts. Replaced the tensioner because it felt a little lose, no change. Turned out the belt that autozone sold me was slightly large which didn't put enough tension onto it when it was installed.

 

[chedderslam]

Hi, thank you for the reply.

I took the cardboard from the belt back to the store and verified that it was the correct belt.

This is not a minor squeal, it is very, very loud. It is very difficult to isolate where it is coming from. A few of the people in the autozone parking lot have listened, and thought it was the alternator. But it was making the noise with both the old and new alternator. I am wondering if it is the tensioner pulley, located below the alternator, that is the problem.

I will try your recommendation today after work. I do have a question though: My assumption is that the tensioner pulley should turn freely, and if it does not, that is the problem. But what about the ac compressor? I am wondering because the car squeals immediately on start up then stops when the heater is off, so I wonder if the clutch is engaged by default when the car is off, and after starting, the system sees that it is not on and disengages the clutch, which might be stopping the squeling? So with the belt off and the car not running(obviously), would the pulley on there turn freely?

Thank you for the help.

 

[dhkmom48]

Sounds like you need another new belt.

Like MY98NNJ said, the belt may be wrong length. Just because Autozone's part number came up that it fits, doesn't mean it is an exact fit. I would ask for a Gates belt part # K060863 for the SOHC 4.0 and part # K060882 for the OHV 4.0.

**note I mistakenly put wrong part # for SOHC belt it is in fact a Gates K060864 **

 

[chedderslam]

Hmm, that's weird. They actually sold me a Gates K060864, not 3. Could that be the problem?

It is
13/16" x 86-7/8" OC
20mm x 2208mm OC

Is the 3 a different size?

 

[chedderslam]

Amazon.com is saying I need a K060864, not 3. I am confused.

 

[chedderslam]

The dimensions of the two are the same. So I have the right belt?

 

[dhkmom48]

Yes you have the right belt I hit the wrong # so yes a gates K060864 is correct

Sorry if I confused you with my mistake

 

[chedderslam]

No problem.

So last night I removed the belt and tried turning everything. The tensioner pulley felt a bit worn and I could here a slight clicking when turning, so I replaced it. Everything else turned fine. Put the belt back on, hoping it would fix the problem, but I am still having the squealing issue.

Any ideas what to try next? I am very frustrated by my inability to find out where the noise is coming from.

 

[RomeovilleIL]

Do you have the old belt still? You can do a couple quick tests - 1. try putting the old belt back on and running - if no noise, then the new belt is rubbing somewhere or is tight enough to induce the noise. 2. Using the your new belt, with engine running and heat turned on (assuming by heater you mean the defrost and have the ac clutch engaged), spray a little belt dressing on the inside of the belt just before each of the pullys one by one to isolate the noise. The dressing usually will quiet it for a few moments if the belt itself is the cause of the noise.

Does the noise happen only when the clutch is engaged with either old or new belt? If so, then I would suggest you at least pull and inspect if not replace. You may find out the a/c clutch or compressor is in the process of going out but was able to slip a little when it was binding using the old stretched belt.

 

[chedderslam]

Talked to a mechanic friend. He said that there may be a washer or other type of spacer that is supposed to go between the idler pulley and the mount on the block. It would not come with the replacement idler pulley as it is not a wear item. Can anyone confirm if there is supposed to be some type of spacer in there? Mechanics/dealer are closed for the holidays so I can't get an exploded view.

Thanks!

 

[windsors03cobra]

If the idler/tensioner pulley turns freely likely there is not a spacer issue. Over by the heater box on the passenger side firewall area there is a big cylinder an A/c drier it has a switch on top it and if you disconnect that wiring plug the a/c compressor will not be loading anymore, the a/c clutch will still freewheel and you said that spun ok. A/c comes on in defrost.

Alternator loads the belt upon start up when the battery needs juice replaced and the blower motor puts a big draw on the alternator and also loads it up and could cause the alt to squeal. Does your tensioner putting good pressure on the belt ? Or is the tensioner tight and restricted from tensioning ?