How do hydraulic flat tappet lifters fail?

Thanks...... so that isn’t a Hylift Johnson lifter.

The metering disc is the Stanadyne “style”, although Stanadyne doesn’t make lifters anymore........ so those could be either Eaton’s that have a different metering disc than they used to have....... or possibly an import(other than Eaton).

As far as I know....... the current Eaton stuff is made in Mexico, since they bought out a manufacturer down there a number of years ago.

The current flat tappet lifter.......well, maybe any type of lifter it seems........ is rather precarious these days.