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Discussion Starter #1
Pat (CAmachinist) has given me some suggestions regarding my oil pressure concerns on SWMBO's new '66-289-2V. Hot idle is running slightly below 20 PSI. He mentioned "loose lifters" a possibility, then left town on a well deserved vacation. Does he mean the fit in the block or the adjustment at the rocker. Would either or both cause the low idle presssure. Above about 1300 RPM it is over 40. The oil pump is a standard Melling - Not HV.Thanks for the input.
 

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Worn lifter bores (in block) can bleed off pressure similar to how a worn main bearing will drop your pressure.
If thats your problem you can have them sleeved and bores to the original specs.
 

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The worn out bore can be the issue....but loose lifters can also mean that the lifters aren't holding any hydraulic pressure (this is what keeps them snug to the pushrod and tight against the rocker arm...)

This is also what makes the hydraulic lifters "self adjusting" (once they have been installed and adjusted....) So that as they wear the tappet friction surface against the cam the hydraulic pressure expands accordingly to take up the slack and keep things tight.

remove intake, valve covers and (personally I would remove cam and lifter to measure the lifter bore tolerances....

if ok...then drop in new cam and lifters (they only cost $130 for cam and lifters) if you're doing this, might as well get a new timing chain kit (go double roller) $49

and install the setup....heck...get a slightly more aggressive cam

you'll notice a performance gain

good luck
 

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Discussion Starter #4
This engine only has break in time in the dyno lab and a little over 200 road miles. The cam is a new Crower "Baja Beast" and all valves, lifters, pushrods etc. are brand new. Builder was a very reputable local race engine builder. Unfortunately, he retired and moved out of state. I would assume that if the lifter bores were oversize, he would have fixed the problem or at least let me know my options. Is there such a thing as oversize lifters? Pushrods, rockers etc. are new. If the adjustment is loose, would that let too much oil leak out of the push rods? Could I have bent a pushrod? Above idle, it is about 40+ PSI which is what the dyno report shows. Thanks for any help and advice. Should I redo the "tappett" adjustment procedure?
 
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