[BimmerNugget]

I just changed my belt, belt tensioner, and idler pulley on my 11' 328.

Everything went smoothly but I noticed that the new idler pulley seems too tight to spin freely. The old idler pulley spins freely while bolted to engine. The new idler pulley seems extremely tight when it's bolted to the engine. It definitely will not spin freely.

The new idler pulley doesn't seem defective, it spins freely in my hand but once i bolt it to the engine it doesn't spin free.

Do new idler pulleys need to be "broken in"?

[Bamaben]

I replaced my pulleys and tensioners and the old and new ones spun with same resistance which made me regret replacing them

[Volasko]

Did you over torque the bolt that holds it down? I had the same experience with Bamaben, when I proactively did my belt. The new one did feel smoother, but spun with a very similar resistance. Sounds like something went wrong, I'd try and check to see if backing off the bolt helps first.

[BimmerNugget]

Thanks, I will try backing off the bolt

[kkasson]

This may sound dumb, but make sure the pulley isn't on backwards. It will bolt up backwards and seem like it's on correctly but won't spin freely

[BimmerNugget]

Originally Posted by kkasson

This may sound dumb, but make sure the pulley isn't on backwards. It will bolt up backwards and seem like it's on correctly but won't spin freely

Shit...let me check. I just kept the metal circle plate on the same side as it came

[Efthreeoh]

New belt tensioner pulleys do not free spin much. Old pulleys free spin quite easily.

[Efthreeoh]

Originally Posted by Volasko

Did you over torque the bolt that holds it down? I had the same experience with Bamaben, when I proactively did my belt. The new one did feel smoother, but spun with a very similar resistance. Sounds like something went wrong, I'd try and check to see if backing off the bolt helps first.

The early printing of the Bentley manual overstates the torque by almost 100 percent.

[BimmerNugget]

Originally Posted by Efthreeoh

New belt tensioner pulleys do not free spin much. Old pulleys free spin quite easily.

No not the tensioner pulley. My new tensioner pulley spins fine.

It's the idler pulley thats the problem. It's extremely hard to spin it. But it spins fine when not bolted to engine.

I went out for 30 minute (8 mile drive) then shut the car off to check the belt. The belt feels really hot. I can only place my finger on it for 3 seconds max before becoming unbearable. Is it normal for the belt to get that hot? I'm starting to think that idler pulley is causing issues.

[Efthreeoh]

Originally Posted by BimmerNugget

No not the tensioner pulley. My new tensioner pulley spins fine.

It's the idler pulley thats the problem. It's extremely hard to spin it. But it spins fine when not bolted to engine.

I went out for 30 minute (8 mile drive) then shut the car off to check the belt. The belt feels really hot. I can only place my finger on it for 3 seconds max before becoming unbearable. Is it normal for the belt to get that hot? I'm starting to think that idler pulley is causing issues.

I didn't realize at first you were talking about the idler. It does have the same tightness as the tensioner pulley when new.