Senior Tech Team
Join Date: Aug 2002
Location: Gold Canyon, AZ
Re: Can too much oil pressure cause problems with hydraulic lifters??
High oil pressure has no affect on hydraulic lifter operation. The clearance between the lifter body and the plunger is measured in millionths of an inch. As I recall (and it's been awhile) the spec is 180 millionths and I think this equates to about 18 ten thousandths of an inch??
Anyway, the hydraulic lifter cavity is filled while the lifter is on the base circle of the cam lobe, with enough oil to move the pushrod to zero lash and then this amount of oil is contained within the cavity, due to the tight clearance between the lifter body and the plunger. You could probably have several hundred pounds of oil pressure before it would affect hydraulic lifter operation and even then it is doubtful that a problem would arise.
64 Chevelle Malibu Sport Coupe (original owner) car now has 427" BB, Jerico 5-spd. trans., Dana 60 rear end.
SAE Member (25+ years)
ASE Master Certified Engine Machinist
AERA Certified Professional Engine Machinist