Ok, got the book on how to check valve lash on a non adjustable valve train for the 5.0 and 5.8 mine is the 5.0 92 vintage. Since noise sounded more on the drivers side only that apart now. 3 points on the crankshaft to measure - IF you have a lifter bleed down wrench clearance from top of valve to rocker arm. What I did today was disassemble and visually inspect the rocker and components and the push rods, everything seemed Ok so reassembled and went thru the process to see without bleeding down how much play in the push rod to rocker. Found one # 7 which seemed tighter than all the rest.

So here's my question, what would cause this ? Perhaps valve face wear moving the installed height up towards the rocker arm, or other possibilities ? If I had cam lobe wear, it would seem to have the opposite effect, correct ? I may order the tool and perform the measurements to see for sure, but wondered about the logic .....

 

Being in Michigan where salty roads are commonplace, I'd bet your noise is a corroded exhaust manifold at the juncture between manifold and head. I bought a 96 E150 van last year with that problem on it's 351. Snow and salty ice got packed in the manifold and melted releasing the salt solution to get in between head and manifold. Put it back together, fire it up and take a bottle of transmission fluid, open it up and unplug a vacuum hose coming from the intake and stick the loose end in the bottle, then rev it up and let it suck up the fluid, that'll make the exhaust smoke up and you'll be able to see where the exhaust leak is. I replaced mine with a new set of coated shorty's also taking the opportunity to build a new 3" single exhaust with a high flow cat. My van spent the first 18 years of it's life in Iowa.

 

Baddad457:

Just a note to say thanks. I installed an exhaust gasket about 3 wks ago and it didn't fix the problem, however after starting to go further decided to check and take some more time to look for a cracked manifold, whatever. So after taking a file to the exhaust manifold sections, knocked 2 old gasket residue pieces and found that my Fel Pro gasket failed on one of them. So used the 2nd gasket in the set to try again. Much better this time. I ordered and received a bleed down wrench and found that by "feel" one of the pushrods had less clearance than others at the crankshaft measuring point .....

Since I need the truck to do some work, will run it and decide at what point the build process (or the 5.8 block) moves forward again .....