valve tap

[steve from staten island]

What exactly causes a valve tap on a otherwise new motor, new lifters, entire valve train and cam. I know the lifter has to pump up but why does it leak after spending some time not running. thanks

 

[oldbee]

Some dirt in lifter or a bad one internally?

 

[lewtot184]

some of the older stanadyne tappets are leakers. I think there could be several factors. I did an engine for myself late last summer using factory rockers but reduced the preload on the tappet from .130" to .075" and there's a light tick if the engine sits a few weeks between start-ups. modern performance hydraulic cams have faster closing ramps and that can create some noise.

 

[Darter6]

Being a low buck kinda guy,I have found the Summit/Jegs brand cams (I have installed 4 of them over the years)all have had the ticking problem after the car sits several days.It stops after the oil pressure comes up. Don't know who makes the cam/lifters for them.It is annoying .
Could it be known as "anti pump up lifters?'' I remember that term from performance cams years ago. Maybe ?

 

[tonysrt]

I had a brand new 71 340 Duster that I bought in 71 and used maybe once a week. I used Castrol oil and had the lifter noise. I switched to Quaker State and the noise was gone. May be a change in oil would help.

 

[lewtot184]

Being a low buck kinda guy,I have found the Summit/Jegs brand cams (I have installed 4 of them over the years)all have had the ticking problem after the car sits several days.It stops after the oil pressure comes up. Don't know who makes the cam/lifters for them.It is annoying .
Could it be known as "anti pump up lifters?'' I remember that term from performance cams years ago. Maybe ?

think they use offshore tappets.