SDB

iTrader: (7)

Is there any kind that is "standard" to use for this purpose?

I was told to get a pair of cheap lifters for my motor, take them apart and put a shim in there to make it essentially a solid lifter, so I could get accurate reading (no flex or compression), and to not use a head gasket and to snug the head bolts down to check for the P-V. I plan on using a thicker head gasket, .074 compared to a .051, and wanted to know if most people check P-V this way, or if they go ahead and put on a head gasket?

Thanks

SDB

Once I use a micrometer or feeler gauge to measure the indentation in the clay, how to I determine P-V clearance from that?

Bo White

iTrader: (59)

Use modeling clay- playdo swells when pressure is released. Just measure the thickness of the clay were the indentation is and that is the actual PtoV clearance.

SDB

iTrader: (7)

cool thanks for the info...

thin layer of oil on top of piston so clay wont stick too bad-
clay on top of piston (how much???)
"solid" lifters for intake and exhaust on one cylinder
no head gasket
torque heads down how much with no gasket (just snug??)
rotate engine by hand one full cycle
pull head off
measure indentation on top of piston with??? micrometer or feeler gauge?
this number is my P-V clearance?
So, I measure the "bottom" of the indentation of hte clay to the "top" of hte piston to get my P-V clearance?

Sorry, new to engine buiding and P_V issues...

Thanks

SDB

Richiec77

iTrader: (3)

You should try to get checker springs. They are low tension springs that basically just keep the valve up. When you measure P-V properly, you should use the gasket that will be used and torque it down to spec to get the most accurate measurement, but you might be able to do it without. I would think that you could do it that way, just remember to add for the thickness of the compressed height of the gasket.

With the clay; not much oil at all. And get an exacto knofe or a razor blade to halve to clay. That way you can accurately measure the indentation. Good luck man.

Oh yea. I don't think I really have to say it, but have all the pushrods out for the other cynlinders.

SDB

iTrader: (7)

Cool, thaks for all the input...weak valve springs may be nice, do I have to replace the springs on all valves, or just one cylinder?

If I use the gasket I plan on using to check P-V clearance, can I reuse it (assuming the motor is not fired, just bolt the head back on and turn by hand)???

Thanks,

DavidNJ

Rotate the engine...ummm...and if the clearance isn't enough, buy new valves and do another valve job?

Hardtop00SS

iTrader: (17)

I was told to use modling clay also, and use the OLD headgasket, and if the P2V clearance isnt enough, flycut the pistons....

RX-Ben

iTrader: (7)

Where are these "solid" lifters available? Also, where are the weak springs available?

Thanks
Ben

Spellbound

I picked up a couple solid lifters from a local engine builder. Call Comp Cams for the checking springs.