Belt Squeal

[scfdbc9]

5.0 GXI. Previous owner added updated bracket for alternator/power steering pump and auto-tensioner. Had belt chirp at beginning of season that led me to investigate pulley alignment. Found that idler pulley is about 1/4 in back from alternator pulley using a straight edge. With aforementioned updates, what do you guys suggest in terms of shimming with washers to get pulleys in line? Which pulley would you shim first? Other suggestions?

A second point tied to the above question. Swapped belts during this process with a quality belt from auto parts store of correct width/length. I know some say yea and others nay on this so bear with me. Belt was quiet and smooth for a few minutes at idle and at higher rpms but eventually started to chirp and squeal like the original belt. Water sprayed on the ribbed side would quiet the belt for a few seconds but the squeal would return. It did not seem to matter at which pulley or point of belt contact that I sprayed, the belt would quiet and then return to squeaking. Oddly enough, neither belt would chirp or squeal at idle, only when throttle was applied. What am I looking at here? Belt tensioner going bad?

 

[Bondo]

5.0 GXI. Previous owner added updated bracket for alternator/power steering pump and auto-tensioner. Had belt chirp at beginning of season that led me to investigate pulley alignment. Found that idler pulley is about 1/4 in back from alternator pulley using a straight edge. With aforementioned updates, what do you guys suggest in terms of shimming with washers to get pulleys in line? Which pulley would you shim first? Other suggestions?

A second point tied to the above question. Swapped belts during this process with a quality belt from auto parts store of correct width/length. I know some say yea and others nay on this so bear with me. Belt was quiet and smooth for a few minutes at idle and at higher rpms but eventually started to chirp and squeal like the original belt. Water sprayed on the ribbed side would quiet the belt for a few seconds but the squeal would return. It did not seem to matter at which pulley or point of belt contact that I sprayed, the belt would quiet and then return to squeaking. Oddly enough, neither belt would chirp or squeal at idle, only when throttle was applied. What am I looking at here? Belt tensioner going bad?

Ayuh,..... Welcome Aboard,...... The 2nd point is moot, til the alignment is fixed,.....
You shim into alignment, which ever pulley that Can be shimmed into alignment,....
Some can't be, others are bolted in the wrong direction,....
I will mention, that p/s pulleys can often times be pressed on further, or pulled out slightly to align it better,...

 

[scfdbc9]

Ayuh,..... Welcome Aboard,...... The 2nd point is moot, til the alignment is fixed,.....
You shim into alignment, which ever pulley that Can be shimmed into alignment,....
Some can't be, others are bolted in the wrong direction,....
I will mention, that p/s pulleys can often times be pressed on furth

Ayuh,..... Welcome Aboard,...... The 2nd point is moot, til the alignment is fixed,.....
You shim into alignment, which ever pulley that Can be shimmed into alignment,....
Some can't be, others are bolted in the wrong direction,....
I will mention, that p/s pulleys can often times be pressed on further, or pulled out slightly to align it better,...

Which pulleys can be shimmed?

 

[Bondo]

Ayuh,..... Donno yer motor that well,......

Would have to be lookin' at it,....

 

[alldodge]

Use a steel straight edge and place against the pulley to see which way the other pulleys need to go. As Bondo said we would have to be there and look at it to determine.

The Power Steering pulley can be moved in/out with a PS puller/installer. The others would need to be shimmed or something else

 

[ripjmk]

I agree with all the above but have to say, to make sure you are checking belt alignment and not just comparing pulley edges. Please do the following:
1. place a straight edge across the crankshaft pulley and with a caliper measure the distance from the straight edge to the first peak between the first and second groove of this pulley. This is your datum measurement.
2. Then holding straight edge across the crank pulley in line with each of the other pulleys in turn, measure the same distance from the straight edge to the first peak. This will tell you true alignment of the pulleys to the belt run.
A lot of pulleys have differing front flange thicknesses and have led them to be misaligned because of this !
You might be surprised by what you find!

 

[scfdbc9]

Thx all for the replies. I’ll get some measurements tomorrow and see where that leads

 

[scfdbc9]

OK, took measurements off the crankshaft pulley and got everything shimmed as close as possible. Checked all of the pulley surfaces for rust and grease, the belt as well. Reassembled and crank back up and within 10 seconds or so the chirping squeal returned. Checked over everything once more and found a slight wiggle in belt tensioner pulley. Checked the bearing in it and could see what looked like a small amount of grease weeping around the edges. Ordered a new tensioner But past that what would be my next step or thing to check?

 

[alldodge]

Rotate the pulleys (idler, tension, alternator, water pump) and try to feel if there is any roughness. Is it a belt squeal or pulley?

 

[scfdbc9]

Rotate the pulleys (idler, tension, alternator, water pump) and try to feel if there is any roughness. Is it a belt squeal or pulley?

All the pulleys seem smooth when spun. Not sure how much free spin should occur afterwards with idler and belt tensioner pulley but I don't detect any roughness....maybe a very slight amount of play.
The squeal disappears for a few secs when I spray water on ribbed side of belt.

 

[alldodge]

Does the V belt sit slightly above all pulleys, not even or lower then top ?

Edit: and what style belt? you said ribbed
edit, edit should be serpentine

 

[scfdbc9]

Does the V belt sit slightly above all pulleys, not even or lower then top ?

Edit: and what style belt? you said ribbed

I'll take a pic when I get home... Not sure how to answer that. Do you mean is it seated down into pulleys? It has had a gator back style from Volvo and a ribbed style from Napa.

 

[alldodge]

I'll take a pic when I get home... Not sure how to answer that. Do you mean is it seated down into pulleys? It has had a gator back style from Volvo and a ribbed style from Napa.

Sorry the ribbed comment started me thinking about ribbed V belt. Yours is a serpentine

It could be that one of the pulley's are worn to bad

 

[scfdbc9]

Sorry the ribbed comment started me thinking about ribbed V belt. Yours is a serpentine

It could be that one of the pulley's are worn to bad

Thank you for the responses.

 

[Bondo]

OK, took measurements off the crankshaft pulley and got everything shimmed as close as possible. Checked all of the pulley surfaces for rust and grease, the belt as well. Reassembled and crank back up and within 10 seconds or so the chirping squeal returned. Checked over everything once more and found a slight wiggle in belt tensioner pulley. Checked the bearing in it and could see what looked like a small amount of grease weeping around the edges. Ordered a new tensioner But past that what would be my next step or thing to check?

Ayuh,....... Get yerself a bar of Lava hand soap,.....
With the motor idlin', find a spot where you can safely hold the bar of Lava against the ribbed side of the belt, 'n rub it right in for 'bout 10 seconds,....
There's a good chance the chirp will be gone,....

 

[scfdbc9]

Ayuh,....... Get yerself a bar of Lava hand soap,.....
With the motor idlin', find a spot where you can safely hold the bar of Lava against the ribbed side of the belt, 'n rub it right in for 'bout 10 seconds,....
There's a good chance the chirp will be gone,....

Thanks much for that. If you don't mind me asking, the Lava does what? Seen it suggested elsewhere....does it clean the belt up?

 

[Bondo]

Ayuh,..... There's pumice in the bar that imbeds in the belt that stops the slip/ squeal,....

 

[ripjmk]

You have shimmed the pulleys as close as possible to be in line with the crankshaft pulley but did you check that they are all parallel to the crankshaft pulley ?