can you post pix?

 

Yes sir! I'm on my way to grab a micro sd card for the inspection camera and I'll post pictures later today!

 

Well....either I dreamed about it last night or my eyes were just playing tricks on me in the dark the other day, but regardless, after further inspection they look like they're contacting just where they should be I thought I was on to something, hahaha, oh well.

 

Well I just finally got everything put back together today. Got my IR thermometer out and got her fired up to see when the noise starts and it really seems like it's almost all the time even from a dead cold start, however it does start to get louder as soon as the coolant temp hits right around 100*F. I did check the fit of the rocker arms to the shafts and they seemed more than sufficient to work and seal correctly. Next thing I was planning on seafoaming everything as a last ditch effort but I figure maybe one of you guys might be able to tell me a little bit more hearing the sound first hand. Other than the noise she seems to run great, no check engine lights, still no fluids mixed etc, no steam cleaned cylinders...besides maybe a compression test do you guys have any ideas on things I might be able to try now that it's back together to kind of point me in a direction? Or at this point should I just bite the bullet and just yank the whole thing out and assume it's trashed? Thanks again guys, I appreciate all of your time.

Video 1(engine bay etc):
Video 2(interior start and idle):
Video 3(interior idle and revs):

 

So to bring this thread back from the dead, I think I've finally found a couple of things wrong. First, cylinder 4 could definitely have a slipped liner as I can just barely catch the edge of it with my fingernail, whereas the others are absolutely flush and true with the rest of the block. Second, I measured the cam end float using the procedure described in the overhaul manual, and my cam is WAY out of spec. It actually acts as if it is going too far back in the block because the thrust plate at the front is actually correct. The manual claims an allowable end float of 0.002-0.014......I'm coming out at 0.146 with my dial indicator, and if you watch the video, you can see with the naked eye how far the cam is physically moving and the noise it makes sounds very close in pitch to what I was hearing with it running. So is there literally it? Is the rear most cam bearing lipped or something to keep the cam from walking backwards? Normally I would assume it's just the cam gear that holds the cam forward while the thrust plate keeps it from walking forward too far, however the overhaul manual specifically says that end float needs to be measured with the cam gear removed.

Here's a picture of the number 4 cylinder, you can see how shiny the edge of the cylinder sleeve is whereas the rest of the cylinders are simply sooty black.

 

Is that a block crack at about 6:40?

......

 

When I first pulled the head I thought it was, however I think whoever recently replaced the head gaskets got it with something. Maybe I can dye test it or something somehow to be sure, but from as much as I could see it didn't seem to be deeper than 10 or 15 thousandths....

 

unfortunately it does look like a slipped iner

 

The cam moving forward over an 1/8" is interesting, probably adds to the clatter noises. Wouldn't matter if you measure off the cam gear or the cam snout it's still the same amount of travel. It's held in place by the lifters being domed as are the cam lobes. Lobes are off center to swirl lifters and not flat spot either. I don't know if a new keeper is going to reduce that gap, might be looking at top hats and a new cam/lifter plus pushrods....... just the beginning.

 

Yeah that is my thinking too. I'm pretty sure the overhaul manual is just incorrect in their measuring method on this one because the cam gear is the only thing that holds the cam from going too far(other than the angled cut of the flat tappet cam lobes obviously) in while the thrust plate holds the cam from walking out. If I put the cam gear on with the thrust plate and dial indicator everything, it's in spec and hardly moves.

I'm planning on all new valvetrain anyways, probably just going to run roller rockers instead of the oe rocker setup, I just flat out don't like it and way too often they seem to develop that annoying freaking valvetrain tick. I'm more than happy to add a little money to the top end to avoid that.

On a side note I had another buddy of mine that's good with the p38 motors listen to my video of it running and he's convinced that it's heavy valvetrain noise, possibly a collapsed lifter. I pulled them all however haven't made it around to testing them yet to see if I have a super weak or a stuck one....it's not like I NEED to find the noise, I'm sure once I build it and everything is in spec again there is no reason there should be any noises, however I'm really trying to satisfy my own curiosity.