This story has a couple of parts. First, the pulley on the PS pump was misaligned and the belt would start working its way off the pulley and riding on the edge. I dealt with that by moving the pulley out from the pump. I thought I had moved it sufficiently.

Next a squeal developed in the general area of the serpentine belt going around the PS pump. A couple of friends suggested that the noise was in fact the result of a misaligned belt. So, I put a straight edge on the PS pump pulley and checked it against the idler pulley (see second photo). It looked to be a little off still (maybe .030), so back at it with the puller.

Thinking all was well (finally!), fired it up and - still squeals. So Ted (the airplane guy) and I looked again. I sprayed a little bit of WD-40 on the tensioner pulley and - voila! No more squeal. For a minute. It came back. More WD-40, same thing. This leads me to believe there is a problem with the tensioner pulley.

A little more background: Gen2 coyote. The engine showed up in my garage (new, crate engine) in June of 2016. First start was not until 2018. It is only on the road this month. The engine has maybe 40 miles on it, but it is 3 years old.

This is where you come in: is there specific lubrication I should have applied to this tensioning pulley? Could the bearing be shot? Other ideas on what could be causing this squeal?

Here's the pump pulley:



Here's the tensioner I'm talking about:



The left-most pulley is the idler (it seems ok); the pulley on the arm to the right of that is the tensioner I reference. Thanks for your expertise!