My Pete rebuild

[Nostalgic]

(05-27-2023 )marek4792 Wrote:  My 870 did that metal screetching whenever it would hit 8000+ feet (Wyoming) then pretty much the next 400 miles after. It drove me up a wall. Mechanic who rebuilt it used a copper spray on the gaskets and/or the surfaces and it actually stopped doing it after that.. but they had forgotten the rings in the manifold so off it went again and like clock work so the noise returned..

I actually considered using copper spray on the head side, and anti-seize on the manifold side to control which side of the gasket that allowed expansion movement. In reality, I think just making the manifold flat again will solve the issue.

When I put it together with new, the center section warped #4 & #5 away from the head. I thought maybe it was just a bad center chunk, so I bought another new center section and it did the same thing after a few heat cycles. I've been running it a year like that and can kind of control it since it only shrieks on 3rd stage jake, and at certain heat/elevation/exhaust flow rates, so I only use 2nd stage most of the time anyway or just ease off the throttle to silence it lol.

Some heavy oversize loads are on the horizon where I'll have to work it a little harder so figured now's the time to just cure it.