Hydraulic Lifters M8

[Jacob1955]

I am pretty sure i have a Lifter leaking off over night,what is the normal time it should take to pump its self back up

[KE5RBD]

shouldn't leak down.  When does may take 3 or 4 or even more minutes of riding.  I had 10 limited leaked down once from riding in trailer for 700 miles and for got and left in gear.  Took couple minutes to pump up.  Was loud also.

[PoorUB]

Shouldn't leak down? When ever you assemble the valve train you adjust the push rods or if using non-adjustables you wait for a while for the lifter to leak down before spinning the engine over, so why wouldn't a lifter that is holding the valve open while the engine is stop not leak down?

All hydraulics will leak down if sitting on the high spot of the cam lobe with the engine off. When the engine is started the lifter should pump up in seconds. My 2016 with S&S premiums takes maybe two seconds, probably closer to 1 second.

[Hillside Motorcycle]

When we load the lifter to .140", there is never any noises upon cold starts.
From .675 S&S cams to Andrews 48's.

[rbabos]

I am pretty sure i have a Lifter leaking off over night,what is the normal time it should take to pump its self back up

If it takes overnight , you have real close tolerance lifters. Takes less then a minute with hot oil on a shutdown. It's how fast they recharge is what's important. With oil present a lifter will recharge in about two valve strokes and never get a chance to clack. This assuming the piston/bore clearances are good in the lifter as well as no leaking check valves.  Key is keeping the feed galley full of oil so as soon as the engine starts, the lifter gets charged. Two things that can skew this is a leaky check valve on a piston squirt where the psi is lower in that particular lifter oil galley at low rpms or use of an oil filter that doesn't have an ADV. That will allow oil to drain back, so the lifter sees air prior to oil. Just long enough to bleed down and start clacking until the air is purged and oil is again present.
Ron