SBC lifter pushrod oiling

[rebelrouser]

I had an engine that oiled the rockers good during the priming with a drill. Ran well on the dyno, but a few weeks later customer hears a squeaking noise. Two rockers were burnt black. Pulled intake off and primed it again with a drill and the two brunt rocker lifters did not oil at all. And a couple others barely oiled. Engine clean as a pin on the inside. Pulled the lifters apart and no junk in them. But when they drilled the hole in the pushrod cup, they did not debur the hole on the inside of the lifter body. The flat disc marked as metering valve had dimples in it from the burs on the cup. I filed off the burrs turned the disc upside down and now all the lifters oil like they are supposed to. Two questions can anybody explain exactly how the disc meters the oil flow to the pushrods, and if a person drilled a small hole to one side on the disc will it increase flow to the pushrods? I drilled one as an experiment and it seems to improve the flow, at least priming with a drill.

[PRH]

I’ve seen a few different designs of the metering disc, depending on the brand of lifters.

They appear to funcition as a means to block direct access of the oil in the lifter to the pushrod seat.

The oil has to make it through the labyrinth the metering disc creates before reaching the hole in the pushrod seat.

Just another problem area to look for...... that shouldn’t exist.
What brand of lifters were they, and what type?

[rebelrouser]

Just stock vortec replacements from local parts store, I really don't remember the brand, maybe engine tech.

[Bill Chase]

Just stock vortec replacements from local parts store, I really don't remember the brand, maybe engine tech.

Probably some of the recent flood of Chinese parts. Look around and you can get American made hrl from people like Steve Morris, bought in bulk and sold at decent price. https://www.stevemorrisengines.com/engi ... nce-1.html Not a plug for him, just an example of where to get a confirmed OEM part at less than dealer pricing.

[Walter R. Malik]

I’ve seen a few different designs of the metering disc, depending on the brand of lifters.

They appear to funcition as a means to block direct access of the oil in the lifter to the pushrod seat.

The oil has to make it through the labyrinth the metering disc creates before reaching the hole in the pushrod seat.

Just another problem area to look for...... that shouldn’t exist.
What brand of lifters were they, and what type?

The Hylift Johnson Hydraulic lifters use a "piddle valve" with 4 holes through it, around the circumference. The middle pushes against the opposite side on the underside of the pushrod seat . That center is extended about .020" into the lifter body and it has the metering slot in it.
If you have lifters with that "Labyrinth disk" it is not Hylift Johnson.

[PRH]

...

[1972ho]

Really recent flood manufacturing of things from overseas sources has been going on since after WW2 if that what you mean by recent.And most lifters bodies have been manufactured overseas for quite a long time some aftermarket companies add the internals.Look it up and you will find out.