Serpentine belt problem

[Schurkey]

I replaced my serpentine belt with a new gates belt. The new belt immediately started a clanking type sound. Researched a bit and decided to replace the tensioner and also the idler pulley. Put belt back on and the noise is still there. Odd thing is, I put the old belt back on and the clanking goes away. What’s my next step? I’m out of ideas. Thanks for any insight.

WHAT VEHICLE? WHAT ACCESSORIES DOES THAT BELT DRIVE?

There was a time when CS130 alternators were an epidemic-failure item. Generally the rear bearing. When one died on me, it locked-up so bad the starter couldn't crank the engine until I pulled the belt off.

Similarly, the R-4 compressor was known to explode internally (which you'd know by now) or the pulley bearing would go rough and have slack.

The symptoms you're describing could be a failure in ANY of the accessories--PS, AIR pump, water pump/fan clutch, etc.

They could also be a pebble stuck in the rib of the belt, or maybe a pebble stuck in the rib of a pulley.

 

[98 Nitro]

X2 on a pebble stuck somewhere. I once had a terrible noise coming from what I thought was a belt but after looking at it for a while it was the tensioner pulley .

 

[BOOT]

My 2009 Silverado has an annoying chirp that comes and goes from one of the pulleys. I've been meaning to take my mechanic scope and listen to each n figure out what one it is, always seem to do it when I don't have time to stop n check or am just being lazy LOL. Some use a pipe or other, just be careful w/e you stick in their.

 

[1989GMCSIERRA]

I replaced my serpentine belt with a new gates belt. The new belt immediately started a clanking type sound. Researched a bit and decided to replace the tensioner and also the idler pulley. Put belt back on and the noise is still there. Odd thing is, I put the old belt back on and the clanking goes away. What’s my next step? I’m out of ideas. Thanks for any insight.

is the replacement belt the correct one in size and length?

 

[Daddyoh]

I replaced my serpentine belt with a new gates belt. The new belt immediately started a clanking type sound. Researched a bit and decided to replace the tensioner and also the idler pulley. Put belt back on and the noise is still there. Odd thing is, I put the old belt back on and the clanking goes away. What’s my next step? I’m out of ideas. Thanks for any insight.

I would first remove the serpentine belt and make sure that your pulley and Balancer are not failing. Both produce a clanking noise when they have started to fail. Engine damage will result like a Broken crank.

 

[Daddyoh]

WHAT VEHICLE? WHAT ACCESSORIES DOES THAT BELT DRIVE?

There was a time when CS130 alternators were an epidemic-failure item. Generally the rear bearing. When one died on me, it locked-up so bad the starter couldn't crank the engine until I pulled the belt off.

Similarly, the R-4 compressor was known to explode internally (which you'd know by now) or the pulley bearing would go rough and have slack.

The symptoms you're describing could be a failure in ANY of the accessories--PS, AIR pump, water pump/fan clutch, etc.

They could also be a pebble stuck in the rib of the belt, or maybe a pebble stuck in the rib of a pulley.

For got to ask in previous reply. What engine do you have in your truck? I assumed it was a diesel by the thread that you posted. But I see by you having an air pump it is a gasser and most likely a 5.7L Gen 1. What you can do though is remove the serpentine belt then run the engine for a short time to see if the clanking is still there.

 

[Roadie]

For got to ask in previous reply. What engine do you have in your truck? I assumed it was a diesel by the thread that you posted. But I see by you having an air pump it is a gasser and most likely a 5.7L Gen 1. What you can do though is remove the serpentine belt then run the engine for a short time to see if the clanking is still there.

Engine is 5.7 gas. I did remove the belt and run the engine. No noise.

 

[Roadie]

is the replacement belt the correct one in size and length?

I assume so. I took the old belt with me and matched it up by length and part number.

 

[Roadie]

Yes, there was no play anywhere. I’m now beginning to wonder if it may be the compressor clutch.

I'm pretty sure the A/C compressor is good. A/C works fine and makes no weird noises. Maybe P/S pump? What other symptoms does a bad P/S pump have?

 

[sntrym]

I had an annoying noise from a pulley a bit ago. Sounded like the PS pump, but when I got my mechanic's stethoscope (really long screwdriver) and put to the P/S pump, no sound. Put it on the alternator, no sound. It wound up being an idler pulley.

To use a screwdriver this way, run the engine, place the flat side on the component (not a part of it that's moving), and your ear to the plastic handle. You'll know it when you hear it.