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Old 10-24-2008, 09:38 AM
red65mustang red65mustang is offline
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"could it be my rings"
it could be many different things and often is a combination of problem sources especially when you are going thru 1/2 a quart (!!!) in just fifty miles....

deceleration, the pcv is held wide open by the extremely high/strong Hg vacuum level, add oil psi is max plus lots of rpms and the carb blades are closed="perfect" conditions for the pcv to suck up oil....

unless your motor will start with no pedal tap at all=no carb squirter pump fuel added,,,then that's alot of extra "liquid" gas into the intake to flush the oil into the chambers so it smokes at start up ....

when you give it a little gas the pcv is probably not full open because there is less Hg vacuum and less oil pressure at the rockers and the mix is lean with a load on the motor so no smoke ....

30 minutes (?) to rig together a oil accumulator, drive it 50 miles and see if still it takes a full 16oz to hit the full mark on the dipstick....

do also retorque the intake, decelerating at 25Hg vacuum can make the heads suck up alot of oil if there is just a tiny tiny intake gasket leak!!!

side note:
vacuum Hg example illustration/analogy,,,, your 2HP wet/dry shop vac with the hose end necked down to about 3/8" diameter "might" be able to pull 12-15Hg max worth of vacuum force on a guage....
at only 12Hg it will pick up ALOT water on the floor fast as hell .....
decelerating/engine braking a motor that seals decent does pull 25Hg+ so think of a pcv as a "super sucker",,,every time you back off the gas the Hg does go to 25Hg for atleast a moment!!!!!

external oil leaks can be a sneaky contributor to oil loss....
wash the motor to remove any oil on the surfaces....
use baby powder/talc powder/whatever fine powder that you can put in your hand and blow all over the motor so any oil will show up
.................................................. .........
"it seemed (???) there was to much crankcase pressure"

how many miles on the motor?
on a brand new motor, until the rings and particular cylinder hone grit finish (correct for the rings type!) are worn in to make a good seal it's common to have some blowby....

for a diy'er, lack of absolute "white gloves test" cleaning before assembly is probably the most common cause,,,machining grit scored the walls so now there is blow by...

if it is indeed "excess" crankcase pressure, it can be due to many things....
I picked this link off google almost a random to cover the most (?) common causes:

http://www.nulon.com.au/facts/Factsheet%20110.PDF

do one test, one step at a time till you can truly "diagnos" the problem source....
LOL, might as well do it in easy to PITA test order.....

if there is next to no oil in the jar after 100 miles, (remove all the plugs and keep them in order for the machine shop) and do a compression and/or leak down test to determine if the rotating assembly is sealing correct and equal on all 8 cylinders....
all cylinders test equal and good psi, then valve stem seals and guides are abit "more" suspect for the oil loss....

adding a breather to the cover with the pcv valve totally defeats the purpose of the pcv.....
the pcv is pulling next to no air "thru" the whole block from the other head cover breathers....
it's just sucking air from the breather on the pcv cover
block off that breather...
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