How do i know if my bearings are bad in my s-trim?

 

Does it spin free? Is there any slop in the pully shaft or the impeller?

Ken R.

 

The unit spins freely, but i can hear a slight knocking sound from it while it is at idle. Still spins up well.

 

You could always take it out and pull the cover and take a look. Its not hard at all. Just pull the pulley then pull that top cover off. It will expose the gears and front bearing. There is a little spring washer in there also, so make sure you know how you took it apart. Looking at it may tell you a little more.

Ken R.

 

My Powerdyne done the same thing at idle. Bearings were shot

 

How many miles do you have on it? Have you noticed a reduction in boost pressure?
M----