me and my son just finished putting dart pro 1 heads crane powermax cam harland sharpe roller lifters ,wilson 92mm intake, 90mm throttle body,crane roller lifters in his 2000 ss Sounds great till it warms up then the rearmost left bank lifter starts tapping and will not quit,till motor cools all the way off we have driven it about 10 miles. we cranked it with the valve cover off and all lifters are oiling well and we have .060 pre load.when that cylender is at tdc you can grab the rocker arm and push the plunger , or i should say pushrod down about 3/8 of an inch does this sould like a faulty lifter, i am afraid to keep driving it and see if it will eventually stay pumped up any input would be appreciated, thanks

 

Sure sounds like it isn't getting oil internally. Crane recommends cleaning them prior to installation, did you do that? I would call Crane in the morning. The lifters usually have a thicker grease in them to protect them until installation, it may be that this isn't fully washed out. Have you tried just letting it idle until good and hot?

 

yes we have let it idle quite a while,like i said with cover off it is oiling o k but when kool you can burry the plunger with your hand