Rebuilt 4.0 w/ valvetrain noise.

['93BajaSport]

I've been helping someone change the engine in their Explorer and we just fired it the first time a little while ago. I expected valve noise until the lifters filled up, but it didn't go away. It improved, but it's still a bit loud. Runs fine otherwise with good oil pressure. We only ran it for a few minutes before shutting down to do some searching and reading about this. It sounds like a V8 with a mechanical cam that could use a valve adjustment. :scratch:

It's a Ford service shortblock with rebuilt heads, "refurbished" dunno rockers, new oil pump, new lifters, and new pushrods that I assume are stock length, whatever that is. We didn't "soak" the lifters, btw.

Do dry lifters take a long time to pump up or something? Should we run it some more before going back into the top end? :scratch: The original 250,000mi engine made no noise whatsoever.

 

['93BajaSport]

Anyone?

 

[Anime]

http://www.explorerforum.com/forums/showthread.php?t=369534

 

['93BajaSport]

I read that thread before posting this one and found it inconclusive, although it is partly the reason I asked if 4.0 lifters are slow to pump up. Turns out that ours were.