Getting the car ready today and had the car started and idling for approx 10 minutes. After I shut it off the overflow tank was full of oil. Also have a newer style moroso oil separator. It was full. 6-7 inches of vacuum at idle. Anyone have a suggestion as to the problem

Might be a dumb question, but were the tank(s) empty when you started it?
Hard to believe it would fill the tanks in 10mins with 6-7" of vacuum.....
Do you know what the vacuum is at going down the track?

Yes. It was a new tank. The only thing that changed on my car over the winter was I had a new set of valve covers made. My fitting used to be on the top inside rail on the intake side of the valve cover. These new covers I had them weld the fittings in the front face in the top corner. Vacuum down track is 12-13

oh, you mean the collection tank for the vacuum pump filled up?
If that's what you mean you need to baffle the fitting somehow or just move it all together I'd say....

The fitting is baffled. Here is a pic of the location

The fitting is baffled. I guess I am going to put my old VC back on and try it. The fittings are in a different location on them. If that fixes it then I will have my new covers fitted with new fittings.

Where is the relief valve? Also check for leaks.

Relief valve is mounted on the pump. Star Machine Standard pump

Maybe smoke the engine and see if it has air leaks. When mine was pulling a little air in one time, my tank would be about half full or so in two passes.

Yeah. I can do that. I can understand oil in there maybe when your making passes. But idling in the driveway for 10 minutes seems excessive

Fitting location,air leaks, and oil drainback issues are the three things it could be. Vacuum level usually has nothing to do with it.

Yeah. My guess is fitting location or oil drainback. I had to crack loose a vacuum line just to get the oil to drain out of the pan.

Ok. Tried the old Valve covers from last year. Fittings in a different location, same issue. Put the old overflow tank on the car. Basically put the car back in the same configuration as last year. With the car ideling for no more than 6-8 minutes. Water Temp between 180-190. It just keeps sucking oil into the tank. Out of all my testing today with different config's it sucked more than 1 qt out of the motor. The engine never went above 2000 rpm today. I guess there is a leak somewhere but how do you have a leak that bad and still pull 7-8 inches of vacuum at idle.

How much oil is in the engine? You didn’t accidentally overfill it by a bunch did you?

Did you try bypassing your new oil separator?

I just changed the oil. Its got 6 qts in it. I took the oil separator off. I have tried several different things.

The reason I asked, a friend changed his oil and his Dad thought he hadn’t added the oil yet and stuck 6 more in it.

Ok. A little more info on this issue. Unhooked the line off the intake of the pump and started the motor. Hung that line in a bucket & warmed the car up to 190. NO oil is being pushed out the line. Hooked the pump back and hung the exhaust line from the pump into the bucket & after approx. 30 sec oil starts coming out the hose at a constant rate. Decided to do a compression test all the cylinders except 6&8 read 190-200. Those other 2 read 130. I then did a leakdown. Every cylinder including the 6 & 8 have less than 5 % leakage.

How can you have hardly any leakage and 2 cylinders are down on compression. I am assuming the 2 low cylinders are having excessive blowby & that's why IM getting oil flowing through the vacuum pump.