exhaust valve keeps going out of adjustment

[6BT2500]

just lost a head gasket, it was only 3months old and blew apart very very bad (coolant in oil,oil in coolant)it was a cummins gasket with new bolts. i just put a new oringed head, arps, and hamilton springs and retainers in the truck flushed the oil changed then retorqued the head . my problem is #5 exhaust valve keeps going out of adjustment i set it at .020 and run the truck for 15 mins and can fit the largest feeler in the gap rocker is firmly seated and studs are well torqued, push rod is also strait. is it me or is the cam wipping out? sorry for the long wright up

truck is a 97 215 govener springs 024's 16deg water and a plate no other mods

 

[Snedge]

camshaft or lifter

 

[CSnyder]

Sounds like a cam issue but have you checked the trueness of the pushrod?

 

[gmcz71502]

I had the same problem with my truck... lifter(tappet) foot broke off and wiped the lobe. sounds like cam time...

 

[KingS]

yep sounds like you cam has seen a better day mine did that on my 96 tappet broke and tore the cam lobe down. put mine was do he the stock lift pump locking up and the foot busted off and hit number 5 tappet

 

[6BT2500]

yes check the trueness of the push rod going to have to rip it apart forgot to mention the truck has .25 millon on it