lol yer ok its not standard rule that holdens have lifters but in this era it is.

u have 12 tappets in ur engin...6 on the exhaust valves 6 on the inlet valves...just remove the rocket gear and lift em out...simplleeee

again, sorry. what exactly do lifters do?

They lift things bruvva.

On a more serious note, lifters are used to open and close valves by the lobe on the camshaft.

Lifters and rockers do the same thing but go about it differently. Rockers are simply an arm that is hinged somewhere near the middle, as the lobe of the camshaft rotates, it pushes one side of the rocker and the other side gets pushed down, this side is pushing on the top of the valve so the valve opens and gas flows.

Lifters are usually hydraulic, the camshaft pushes on a surface that pushes oil through and pushes another piston to open the valve. Same concept, different implementation.

Tappets/Lifters transmit the action of the cam shaft to the valves. ie open the valves.
Hydraulic lifters take up the lash to reduce the noise.

thank christ you lot dont have to work on engines to put food on your table (flyingnunrt excepted)

tappets and rockers are the same thing, just different names

lifters are also known as camshaft followers (funnily enough cos they follow the profile of the camshaft lobe)

Typical non OHC drivetrain:

OHC Drivetrain with rockers



flyingnunrt is right, the biggest function of hydraulic lifters is to hydraulically adjust the valvetrain to compensate for machining tolerances and wear on the camshaft, etc

you can also get solid lifters, but due to the tolerances that have to be built in (due to expansion of the metals when they are heated) they're noiser than a hydraulic setup, and as they arent self adjusting, you gotta adjust the rockers to compensate for the wear on a regular basis

thanks mate, i think that helped. may have to stare at the diagrams for a few more hours, but i'll understand eventually.

oh, i forgot to mention, if the seals on the hydraulic lifters are f**k, the oil gallery to the lifters is blocked, the oil feed hole in the lifter is blocked, or the oil is too thin (meaning the oil will bleed out of the lifter past the seals) the lifter wont pump up and adjust for the clearances, causing the ticking noise