Need some help - loosing oil pressure at high rpm's

[Rick Parker]

After capping the lines, if there is no change, it could unfortunately be an indication of loose bearings.

ALSO: You might have a crack in the oil pickup tube, or depending on static volume of pan, you could be pulling oil out of the pan faster than it can drain back in to keep the pickup submerged and prevent a vortex.

[madmaxx]

Excellent points! My first thought. That is why I dropped th pan and determined the dipstick was off 1.5 quarts at full. I checked pickup to pan and it was 1/2 inch. Pickup pipe was good however I did find where one of the button head screws on one of the baffle support was rubbing the line and would eventually run a hole.

Po called and said original cooler had a leak. This one was installed a month ago. A long time I talked with Mellon and they said the hv pump volume reaches maximum at 4 k rpms and really taper off. Funny that is where I notice the quick drop and stabilization.

Originally Posted by Rick Parker

After capping the lines, if there is no change, it could unfortunately be an indication of loose bearings.

ALSO: You might have a crack in the oil pickup tube, or depending on static volume of pan, you could be pulling oil out of the pan faster than it can drain back in to keep the pickup submerged and prevent a vortex.

[Gaz64]

Your cooler and lines aren't big enough.

[Caprimaniac]

Originally Posted by Gaz64

Your cooler and lines aren't big enough.

As he said. Should be AN10 in oil system, someone told me....

Can you use the 90 deg filter adapter?

Also try removing the oil cooler to see if that helps, if larger lines do not so. You have a thermostat plumbed in?

Maybe oil pump "whipps" the oil like some water pumps do at high revs????

It doesn't seem like your pickup/ pan is a issue.
However; at higher speeds- more sucking- more vacum around the pickup and the pickup glue to the floor. There goes your lower pressure at higher revs.

After all your oil PSI looks OK even if it drops; doesn't seem too low.

[olddog]

Max I understand your frustration.

If you can get an oil pressure reading at the connection where the oil returns to the engine, we will know if the pressures drop is happening in the line, or if the drop is inside the engine. It is possible that there is another teflon fur ball in an oil gallery inside the engine. Let's hope it is the external line.

[N2Cobras]

Originally Posted by Caprimaniac

As he said. Should be AN10 in oil system, someone told me....

Can you use the 90 deg filter adapter?

Also try removing the oil cooler to see if that helps, if larger lines do not so. You have a thermostat plumbed in?

Maybe oil pump "whipps" the oil like some water pumps do at high revs????

It doesn't seem like your pickup/ pan is a issue.
However; at higher speeds- more sucking- more vacum around the pickup and the pickup glue to the floor. There goes your lower pressure at higher revs.

After all your oil PSI looks OK even if it drops; doesn't seem too low.

Water pumps are a centrifugal pump, oil pumps are a positive displacement pump, totally different pumping concepts/how they react, sorta like a turbine vs. an internal combustion engine. PD pumps won't "whipps" the oil unless they suck in air with the oil. (I'm reading all the old SBF posting and this looks like something that needs to be corrected for future searching referencing, feel free to ignore this if you already knew pump engineering.)

[PLDRIVE]

Max its the resistance in the cooler and or the lines. I have had the same issue before (Remember u disagreed with me ).
The fix = make a more efficient oil circuit, or change the spring in the pump. I have always ended up changing the spring.

Mark

[madmaxx]

Interesting i have alot of thinking to do it should pump the volume!!!! What do you mean by changing out the spring. The one in the oil pump. It has an adjustment and I did turn it in about 3/4 of a turn. I could have gone a lot further. To be honest I don't know how much it was engaged until I turned it in. So if the pump Rv is theoretically reset to 80psig will that solve the issue? Is it possible the pressure drop across the cooler will just grow with higher pressure/flow and never supply the engine.

As far as plumbing standard superformamce an 10 hoses and fittings identicle to my last one. My last one had a 7 psig drop across the cooler(stock SPF) I have a lot of data from my oil filter experiment a couple years back. By the way on this one I use 3.99 ford fl1a from walmart with Mobil 1 10w40 high mileage ( extre zinc/phosphorous.)

Originally Posted by PLDRIVE

Max its the resistance in the cooler and or the lines. I have had the same issue before (Remember u disagreed with me ).
The fix = make a more efficient oil circuit, or change the spring in the pump. I have always ended up changing the spring.

Mark