I rotated the engine until I felt pressure on the test hose, then rotated until the piston was at its highest peak(TDC). When I pressurize the cylinder, I can hear air coming from the exhaust manifolds. If I slightly turn the crank clockwise I can feel resistance (pressure) and the leak pretty much stops. The leak gauge will also move back to the 'yellow' moderate loss area.

Maybe the input pressure is turning the crank enough to slightly open the valves?

 

valves shouldnt be open at all during the power stroke. and while youre at it you may want to check the plenum.

 

Yeah, sounds like you are just 180* off. Pulling the valve covers and verifying both valves are closed is a good idea.

 

Will do.

I'm most likely going to replace the heads anyway as part of the rebuild but I've been curious as to the actual condition of the motor I bought.

 

Pull the heads, and scrap 'em. That's about all they are good for anyway.... Check cylinder bores, and if they are within spec, just hone 'em up a bit, and put in some new rings. Don't forget to fix the plenum.

You can get a good set of replacement heads from Odessa, or, Clearwater Cylinder head in florida. (both the same company.) They have better-than-stockers for under 300 each.

 

Roger that.

Is the main difference in the stock vs. Clearwater/Odessa the strength of the castings?...more strength between the valve chambers? Same valve/spring specs as the stock setup right?

At a quick glance it appears that it would cost me more to put the stock heads back together with new parts than it would to buy a preassembled set.

 

Exactly. On both counts. The O/C heads have thicker deck castings. Far less prone to cracking. You can order them up with better valve springs as well. in case you wanted to cam it a bit while you have it apart.

 

I think anything other than stock duration/overlap is going to cause me a problem when it comes to emissions...at least that's what I gathered from my conversation with Comp Cams Tech Support...so, I'm thinking I'll leave well enough alone and stick with stock cam. I guess the added duration could exceed the allowed emissions?? I may have to do some more research on that.

 

You should be able to do something like an RV cam, and not totally hose your emissions. Not like they are going to tear down your engine and spec your cam.... So long as you exhaust is up to spec, they won't care. With a good running engine, and a cat, you should be fine.

 

Since we're talking emissions...

I'm inside digging through the '96 and '01 service manuals. This little booger is attached to the right/rear of the intake...looks to be a purge solenoid and judging by the vac lines connecting to it I'm sure that it is. This 5.9 is a '97. Did the purge noid used to be mounted to the intake? My '01 3.9 has it on the pass wheel well area.