Do you need a decoupler pulley for a serpentine belt?
A special tool may be needed when replacing a serpentine belt or automatic tensioner on a transverse-mounted engine in a FWD vehicle. The tool has a long, flat extension handle that allows a socket to be placed on the tensioner bolt or flats on the tensioner arm. Some alternators have a decoupler pulley.
When to replace idler pulley and belt tensioner?
If the automatic belt tensioner has failed (and the engine has a lot of miles on it), it’s probably a good idea to replace the idler pulley (s) at the same time. Why? Because the shaft bearings on all the pulleys will have the same amount of wear.
What to use to replace serpentine belt tensioner?
Using your ratchet with a slim head (I’m using a torque wrench) and a pry bar, carefully get the ⅜” square drive into the belt tensioner. This is when the pry bar becomes your best friend if you don’t have a serpentine belt tool as you need just a little bit of room to get this in.
Can a ratchet be used to remove a tensioner pulley?
To speed things up a 3/8” drive ratchet with a 15mm socket can be used to remove the idler pulley, but there is not enough room for the ratchet for the tensioner pulley. A ratcheting wrench works well for this. Another thing to know is how the belt fits on your vehicle.
If the automatic belt tensioner has failed (and the engine has a lot of miles on it), it’s probably a good idea to replace the idler pulley (s) at the same time. Why? Because the shaft bearings on all the pulleys will have the same amount of wear.
When to replace a serpentine belt tensioner?
Repair Topics > Belts Serpentine & Timing > When to replace serpentine… Let’s get this straight from the get-go, a serpentine belt tensioner doesn’t last the life of the vehicle. In fact, most start to show serious wear right around the 100K mile mark. You may think a worn tensioner just means your belt loses tension; you’d be wrong.
A special tool may be needed when replacing a serpentine belt or automatic tensioner on a transverse-mounted engine in a FWD vehicle. The tool has a long, flat extension handle that allows a socket to be placed on the tensioner bolt or flats on the tensioner arm. Some alternators have a decoupler pulley.
How does a belt tensioner and pulley work?
The tensioner, harmonic balancer and decoupler pulley work together to keep the belt in contact with grooves in the pulleys. The three components are engineered together to match the engine. If one part is compromised, all of them are compromised, including the belt.