Mobil-1, if you don't choke on the cost, does a good job at cleaning
sludge and varnish out of the engine over the course of a few changes.

Allan
--
1991 Vanagon GL

Mike <mbucchino@CHARTER.NET> writes:

>  They should be hard during/ after running; they will leak down over
> time just sitting. The adjusters must have been improperly set, if
> the lifters pumped up to the point where the valves were unable to
> fully seat.  Now that they're fully 'pumped-up', you should be able
> to set them a little looser, which you seem to have already
> done. The lifters have a non-return check ball that allows oil
> pressure in, but won't let it out.  The lifters are basically a
> small 'piston' inside of a 'cylinder'. The inner 'piston' can get
> stuck on varnish deposits or dirt particles in the 'cylinder',
> rendering the adjustment capabilities useless.  Hydraulic lifter
> engines need to have the oil/ filter changes done religiously due to
> this fact alone.  Dirty oil will force you to overhaul these
> delicate mechanisms before the normal timeframes.  Some people pour
> in oil additives to 'clean' their lifters.  Maybe this is good
> remedy for your engine?
>