[XXbigblock]

Working on a big block in a 4x4. Owner bought it at an estate auction so nothing is known about it. It sounds good, runs good but it uses a quart of oil in 500 miles. I ran it hard up and down the road with a friend following and It never let out any smoke. I took the plugs out, they looked fine. I did a cylinder psi test, all are good. For the hell of it I leaked it down, once again, it's fine.
It definitely has a high psi oil pump. Cold Idle around 70 psi, hot around 55 psi. I took the breathers off and both have a milky film in them looking from the underside up into the breather. It's a dirty, somewhat leaky engine but nothing has dripped on the floor under it.
My thought at this point is that oil pump. With that much psi could it be creating so much windage that it is coming out the breathers and causing the leaks ? At first I thought it was strange there was no pcv on it, but maybe there was one at one time and it was removed because of plugs fowling.

 

[The Mad Porter]

More often than not high oil usage like this is due to valve guides. Excessive clearance and or seal issues.
Second issue can be oil getting sucked into the intake ports at the floor due to improper intake sealing.

Remove the pcv valve, plug the hole and see if you have any vacuum at the vent on the opposite valve cover.

I've seen exhaust valve guides send oil into the exhaust as well.

Oil psi in and of itself in not an issue here. Leakage from bearings would be if it was such that it overwhelms the rings.

Glazed cylinder walls can be an issue as well but it is not common.


SJ
used2b RHP


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[Dan the ranchero man]

I had a 460 with aftermarket valve covers that did not have any baffles on the inside were the oil cap and PCV valve would go into. Turned out I was sucking all my oil through the PCV, put a stock set of covers back on and never needed to add oil again between oil changes.