850 Hydraulic Lifter tests

[Gizmo]

Hey gang. Can't get straight answers on this... How can I tell if my lifters are good enough to go back into the head w/o a rebuild? I dont recall any lifter noise when my engine was running, but she's got 125k on the clock and when the economy bit the dust so too did my vigilance about oil changes...

The lifters are all firm by hand. Some people seem to say this means they're good. Others say this could indicate that they're very very dirty inside. Hitting them on a wood block doesn't cause the center to pop out.

It should also be said that they've been out of the engine for four months or so now, as I've been slowly building the head back up. Money's tight, so I can't just get a new set, but I don't know if I should rebuild them or not.

 

[vvpete]

Fill them with oil and when you press on the center section oil should not bleed from the outer section for a while, like 20-30 seconds. This is how I've checked old Ameican V8 lifters, but the 960's are similar. If you think they're dirty, fill with very thin oil and do the above several times while dumping the oil out each time.
The early B6304 engines had lifter problems, but 96 and later are a better design, should be good for 200k miles

 

[Gizmo]

excellent, thank you. Should I be able to work the piston by hand when they're filled?