Ok guys to start off with Im an old time mechanic, and never really ran into hydraulic lifters until this 86 f150 302 efi v8, anyway Im clueless as to how this works Im as far as the push rod pushes up but thats it, nothing else I see makes sense... also theres a nut where the rocker arm would pivot to push down on the valve... Could anyone shed any light on how any of this stuff works? Any diagrams or even drawings would be extremely useful...Thanks guys for any insight on how this works. Im trying to chase dwn a knocking noise coming from the valve covers, and it increases with engine rpm... usually on older cars you could just adjust the lash and be good to go, but this is a whole new ballgame.

 

You can adjust valve lash with hyd. lifters. You run the engine with the valve cover off. loosen the nut until it starts making noise. slowly tighten it until it starts to miss. then loosen until it runs smooth agian. If it just started you might have a bad lifter or one that is clogged with sludge. You can sometimes run an engine cleaner i the oil and free up the sticky lifter without all of the mech. work. The hyd. lifter runs off the cam, one end rides the cam, the other end has the rod in it.

 

O so the hydraulic lifter is actually in the bottom of the engine on the cam..? I think I'll try the cleaner first... do you recommend seafoam? Thankyou for the help

 

I see that mentioned quite a bit in the diff. threads. Most people seem to like it. I know that there are several types on the market. good lick and let us know how it goes.

 

You might also try adding a pint of Marvel Mystery oil to the crankcase oil. I have seen it work wonders on freeing stuck lifters.

SeaFoam is good stuff as well but I am not sure how it works in the oil. I have only used it in fuel. For that it is the tops.


tom

 

Sometimes you can just add a quart of transmission fluid to it, because transmission fluid is a detergent. Which can unclog the tapping lifter. Usally when you start getting the tapping sound, its usally a bad lifter. Then if you have to replace the lifter, go ahead and replace all of them.

If you decide to adjust your rocker arms, be very careful. You can damage your push rods and cam. Even thou they are Hydraulic, your lifters can create alot of force once they are primed and solid.