Express & G-Series Vans Offered in both a full size van, or a large box truck, the Express is the modern GM workhorse

Chevrolet Express
Platform: GMT Van

Noise Noise Noise, Squeek around the Serpentine Belt, Need to locate the problem

Thread Tools
 
Search this Thread
 
Old April 17th, 2016, 7:58 AM
  #1  
CF Beginner
Thread Starter
 
DSD-2016's Avatar
 
Join Date: Apr 2016
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default Noise Noise Noise, Squeek around the Serpentine Belt, Need to locate the problem

So all of the easy stuff has been done. Replace Belt, Replace Tensioner, Replace A/C compressor, Replace Idler Wheel, Replace Alternator, So the only 2 pulleys not replaced are that for the fan, ( its not squeeking there ), and that for the Harmonic Balancer pulley and balancer.

Ok now here is a twist, since the truck has 165,000 miles on it, it has developed small leaks around the oil pan and around the cam covers. So since I do see slight wetness of oil on the balancer wheel behind the pulley for the belt, could the problem with squeaking be that ??? I am trying to test all things before actually replacing the harmonic balancer and the pulley in front of it that holds the serpentine belt.

I also feel I need a good boom microphone so I can isolate where the noise is coming from. Any and all ideas welcome, since the weather is breaking to the nice side and would like to get started on it.

2002 Chevy Express 3500 5.7 EFI

Last edited by DSD-2016; April 17th, 2016 at 8:08 AM. Reason: needed to add model
Old April 19th, 2016, 5:09 PM
  #2  
CF Veteran
 
canucklehead's Avatar
 
Join Date: Dec 2012
Posts: 1,584
Likes: 0
Received 6 Likes on 6 Posts
Default

Water pump?
Old April 19th, 2016, 7:13 PM
  #3  
Super Moderator
 
tech2's Avatar
 
Join Date: Mar 2011
Posts: 9,169
Received 507 Likes on 467 Posts
Default

mechanic stethoscopes are helpful
sirometers are an innovative why to check for bad pulleys.


you replaced only the serp belt not the a/c belt? was the noise still present right after belt replacement?


if you spray the belt with brake cleaner, does the noise go away briefly?
Old April 20th, 2016, 5:29 AM
  #4  
CF Beginner
Thread Starter
 
DSD-2016's Avatar
 
Join Date: Apr 2016
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default Oh ya almost forgot

Originally Posted by canucklehead
Water pump?
Will check that, I suppose I can remove the belt and try spinning this system to see if it is making noise, currently no overheating problems. Thanks again.
Old April 20th, 2016, 5:33 AM
  #5  
CF Beginner
Thread Starter
 
DSD-2016's Avatar
 
Join Date: Apr 2016
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

Only one belt no A/C belt, I have a regular stethoscope hard to get in there, might have to start disassembling the front area, radiator, A/C stuff etc. Noise does vary with addition of Belt Dressing on the belt, belts have been replaced enough to know its something else. I will get this problem but the whole darn front end might be on the ground to get to it, haha ouch.
Old April 20th, 2016, 8:52 PM
  #6  
CF Veteran
 
cleveland63b's Avatar
 
Join Date: Feb 2012
Location: nebraska
Posts: 1,433
Likes: 0
Received 0 Likes on 0 Posts
Default

have you tried taking the belt off and running the engine? would give a solid answer if its belt/pulley related or engine.
Old April 21st, 2016, 12:17 AM
  #7  
CF Veteran
 
canucklehead's Avatar
 
Join Date: Dec 2012
Posts: 1,584
Likes: 0
Received 6 Likes on 6 Posts
Default

....running the engine for 30 seconds max.....without internal waterflow....
Old April 21st, 2016, 7:03 AM
  #8  
CF Beginner
Thread Starter
 
DSD-2016's Avatar
 
Join Date: Apr 2016
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by cleveland63b
have you tried taking the belt off and running the engine? would give a solid answer if its belt/pulley related or engine.
Yeppers, have done that and it doesn't squeak with the belt off. I am starting to lean towards it might be water pump.
Old April 21st, 2016, 7:05 AM
  #9  
CF Beginner
Thread Starter
 
DSD-2016's Avatar
 
Join Date: Apr 2016
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

One thing I saw that I didn't like was I tried running the car with the radiator cap off, and normally I would see a flow of coolant with a healthy water pump, but instead it was stagnant and just flowing over slightly. Might be an indicator of the water pump being the issue. Dunno really.
Old April 21st, 2016, 7:50 AM
  #10  
CF Beginner
Thread Starter
 
DSD-2016's Avatar
 
Join Date: Apr 2016
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

So the 3 mystery pulleys now are the Power Steering Pulley ( don't think the sound is there ), the Camshaft / Balancer pulley, and the Fan Clutch / Water Pump pulley. No way for me to tell just listening to it so might be a process of elimination.

Now the next issue is Duralast which is a little cheaper worse than the AC/Delco, Since Chevy uses AC/Delco might try that tensioner and belt combination a ( 100 dollar test 8-( )

Last edited by DSD-2016; April 23rd, 2016 at 7:35 PM.




All times are GMT -5. The time now is 2:55 AM.