Valve to piston clearance

dartfreak75 said
Even if the hydraulic lifter collapsed wouldn't the play doe be soft enough to get a full impression before it collapsed? Surely the spring in a hydraulic lifter Is strong enough to impress playdoe?

No, the hydraulic lifter plunger will bleed down when you put a load on it....

Some people tear them apart and make a solid shim to hold the plunger in place to keep it from bleeding down and making your measurements incorrect...

If you could set the plunger at it's bottom and then set your adjustable rocker to zero lash it could work...

The goal is to keep the plunger from moving down when you are measuring... It can throw off your measurements..