2004 GMC envoy, should the a/c pulley turn freely with the belt off?

If there is no diagram pasted in the engine compartment, check your owner's manual...or else go to your local auto store warehouse or Chevy dealership...usually the parts counter person can print out the diagram specifically to your vehicle. Since you did not mention the engine specs- I'm going to generically how to install a serpentine belt.

1.) make a loop and slip the loop around the crank shaft pulley
2.) continue looping the belt around the water pump pulley
3.) ...around the A/C pulley
4.) ...and around the idler pulley
Skip the alternator pulley for now- you want to do that one last.
5.) Continue placing the belt around the power steering pump pulley
6.) and over the belt tensioner pulley
7.) Now move the belt tensioner position so that you can loop the belt over the alternator.
8.) Now double check to make sure that the belt is properly and securely fastened around each pulley's grooves. Don't start the motor until you are absolutely sure... and can visually verify that the new belt is installed properly. And don't have anyone (or pets) standing around the car or open engine compartment when you initially start the car just in case the belt breaks...serious injuries can occur!
I've attached a generic drawing it may or may not fit the description of your auto.

-Replace new one or remove it and use shorter belt.


Good Luck


mai

Yup. It hasn't started leaking yet but it will soon. Get the pump replaced.

Throttle body needs to be cleaned front and back. Disconnect battery while doing the cleaning to force PCM relearn.

I guess my first question would be are you sure you got the right replacement belt ? And are all of the pulleys on straight ?
Is the belt slipping, or coming off ?
Was the original belt giving you problems ?

When the A/C is not being used, the A/C compressor pulley should be free wheeling. So disconnecting the A/C will not help. Pull the belt off and spin the A/C pulley by hand. If it turns freely, and no noise, the problem is elsewhere. Check the pulley on the alternator and the other pulleys. If all appear and sound okay, try a new belt.
If the squealing only happens when the A/C is used, it could be a bad compressor, but again, the pulley should be free wheeling when A/C is turned off. If it is not free wheeling, disconnecting won't make any difference-you will have to replace the compressor.

The tensioner pulley may be faulty. There should be a lot of tension on the pulley to keep the belt tight. If the tensioner can be moved easily, it should be replace.

The tensioner pulley has a 3/8" square hole it. You can use an extention with no socket, turn it clockwise, this will release the surpentine belt.

If the fan is attached to it than it is the water pump making the noise and it will need to be replaced. If the fan clutch is not attached to it than it is either the idler pulley or the tensioner pulley. The tensioner is on the passenger side (left) of the front of the motor.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

The Belt Diagram should be on the underside of your hood, however they have a way of disappearing.

If it is not there:
Click on the following free direct Link. It has the correct Serpentine Belt Diagrams for your 2004 GMC Envoy for either your 4.2L 6-Cylinder or 5.8L V8 Engine and Engine Options (AC/No AC etc.). Included are Instructional and Directional Diagrams for your use.

Let me know if this helped, or if you have additional information questions. Feel Free to contact me at FixYa.com!

http://www.2carpros.com/car_repair_information/year/2004/make/gmc/model/envoy/2004_gmc_envoy_drive_belt_routing_diagram.htm

"HOW TO":
Standard Rules to Removal the Serpentine Belt with an Automatic Tensioner:
1. Find the Tensioner(s). (See Diagrams on Link)
2. Using a Serpentine Belt Tensioner Tool, Or Wrench OR Ratchet, Rotate/Move the Tensioner USING THE AVAILABLE NUT (on the Pulley or Arm Base) OR the OPENING (3/8ths or 1/2 inch square opening) rotating the Tensioner Pulley/Arm - moving it away from contact with the belt and towards the area where the belt is not in contact with the Tensioner Pulley. The Tensioner is spring loaded, and is hard to rotate/move.
3. Remove the loosened belt off one of the other more easily accessed Pulleys.
4. DO NOT quickly release the Tensioner, but gently allow the Tensioner to rest in its closed position.

Standard Rules for Installing the Serpentine Belt with an Automatic Tensioner:
a. Pick a Pulley that is most easily accessed. This will usually be on top. This will be the last Pulley that the belt will go on.
b. Using the Diagram: Install the new Serpentine Belt on the remainder of the Pulleys....over, under, left right.
c. Using a Serpentine Belt Tensioner Tool or Wrench or Ratchet Tool: Rotate/Move the Tensioner Pulley/Arm "away" from Belt contact area on the Tensioner. This spring is pretty hard and with a new belt, it will be even harder to install. Rotate/Move this to as-close to the maximum allowed inorder to have enough slack in the belt to get it up and over the last pulley.
d. Using your other hand - Pull the Belt up and over the Last remaining Pulley.
e. Before releasing the pressure on the Tensioner, visually inspect the remainder Pulleys and the Belts' Positioning on them.