Markm10431

Iwas tryoing to localise the tapping in the engine I posted about, and it's gone after a couple minutes.. It's got me wanting to drive the car and live with it but I fear screwing the engine up

74droptop

Sounds like a lifter is sticking to me.

JMNBRZ

:iagree: When your car warms up the oil pressure goes up and helps free the lifter... real easy fix if you take your intake manifold off... that and your valve covers and rocker arms/ push rods.

Drew M

If you let that go for too long, will there be too much damage? I think thats happening in my DD.

jpatrick636

If one of your lifters is slightly out of adjustment, it could be loose when cold untill it expands with the heat. I would check adjustment. If you have a high mileage car, normal wear in the lifter and the push rod can cause a "loose" condition. Dirty gummed up lifters will make noise also. Eather way, it's time to pull the valve covers and have a look.

page62

I have a noise like that. I let Lars listen to it when he visited our town. He simply said not to worry about it. So I don't...

Marv

The vacuum operated heat riser actuator-if you have one- has been known to make these strange sounds until it fully opens around 120 degree water temp. Try pulling its vacuum hose to test this theory. (don't forget to plug the hose!) Good luck.

comp

:cool: didn't think of that one

Markm10431

I worry about EVERY noise it makes.. I need to change the oil anyway.. whats't the best way to thin the oil/clean the passeges if this lifter is gunked up?

Twin_Turbo

????? Pressure is resistance to flow due to a restriction (bearing clearnaces in the case of an engine). As oil gets hot viscocity goes down and so does the oil pressure (at steady rpm of course, pressure goes up by rpm because pump creates more flow)

gliot1

I agree with Mary...It's most likely the vacuum canister for the heat riser. Mine was tapping like that too. I thought I had major engine problems. It was just a loose vaccum hose to the cannister. A $.02 tie wrap fixed it.

Larry B.

Sounds like a lifter is out of adjustment. Just adjust the valves per the service manuals (3/4-1 turn past zero lash) typical Chevy set-up.If any of them won't adjust then you have a bad lifter. Most likely it is just an adjustment. Most of these engine have press in stud that like to work there way out over the years. It may only be a few thousandths but it is enough to make the lifters out of adjustment.