Oil Pressure issue after lots of searching

[66NCVW]

Ok I got my motor back together and up and running. I did change the oil pump and went to a remote oil filter etc. My oil pressure when idle is low. Like under 10lbs. As soon as you touch the throttle it jumps the required 10psi for 1k rpm. Here is a video of us on the rev limiter set to 3k. It goes up to 30psi... as soon as you come off it goes under 10psi. Could this be bc I did use a gasket between the pump and the aluminum cover that came with the full flow kit? I'd hate to tear the motor all the way back down to chase a ghost if this could be the problem.


Under 10psi at warm idle with rotella 15w40. Drained that out after break in and put 20w-50 in and got a 5psi or so jump.

Thanks in advance everyone!!
PS: Sorry for the upside down video, but it was the best shot of the oil pressure gauge. The white numbers that the needle is over when on the limiter is 20psi. So its about 25-30ish give or take

[ps2375]

The stock oil light switch is set for something like 2.5psi, so below 10# at idle is no real problem. Why would you put something like 20/50 oil in a freshly rebuilt motor? Too thick an oil will cause high oil pressures which will cause the oil to bypass the oil cooler and then the motor runs hotter. The thinner oil allows the oil to flow thru the oil cooler almost all the time and thus run cooler. And, unless your gauge has been calibrated recently, it is nothing but an "educated guess" at what your actual pressure is.

[66NCVW]

We put in the 20/50 to see if the pressure would go up or if it was a sure internal problem. If I can get the pressure back up with the 15/40 I will. Keep in mind the car has been in a shop thats climate controlled so it hasn't been below 50F to get the oil thickened up anyways. My concern is super low pressure and the turbo getting the oil it needs. I've done a lot of reading that says don't worry about it "vw's have low pressure" that just seems really low. And there are folks claiming 25psi hot idle oil pressure

[ps2375]

Thick oil doesn't mean more oil is flowing to the places that need it. And the turbo is barely turning at idle speeds, that would be the last thing I'd be worried about. Have you checked the pump cover clearance? Sounds like you have a new to you pump and then also a new to you cover, seems you may need to do some additional measurements.

[66NCVW]

Thick oil doesn't mean more oil is flowing to the places that need it. And the turbo is barely turning at idle speeds, that would be the last thing I'd be worried about. Have you checked the pump cover clearance? Sounds like you have a new to you pump and then also a new to you cover, seems you may need to do some additional measurements.

Yeah, thats what I was saying in the original post. I have a new oil pump, and a new cover. I didn't know about the end play situation on the newer oil pumps. I think if I set that everything should be a OK. I know that more pressure doesn't = more flow.

[ps2375]

I don't run a turbo, but I do have around 10# or so at hot idle with 5/30 oil, I don't have any worries for my motor. There is no need for 25psi @ hot idle. If they have that, they have way too much oil press everywhere else, and depending upon how they are cooling their oil means they may not be cooling the oil.

[66NCVW]

I don't run a turbo, but I do have around 10# or so at hot idle with 5/30 oil, I don't have any worries for my motor. There is no need for 25psi @ hot idle. If they have that, they have way too much oil press everywhere else, and depending upon how they are cooling their oil means they may not be cooling the oil.

That does make me feel a bit better. I'll adjust the end play on the pump and give her another try with rotella 30w

[Piledriver]

You may need to pull the pump and lap it for zero end play, then the gasket sets the end play.
Aftermarket pumps also usually seem made to slide in easy (may have a "tight" stud hole) which is the last thing you want.

10 PSI hot idle is perfectly fine, great even.
Run the right oil or risk the pressure-based "thermostat" bypassing the cooler, raising the oil temp as it will until the pressure drops, as it was designed to do.

I've been running a 5W30 oil since beginning of summer. In Dallas. With AC.

[Marc]

You may need to pull the pump and lap it for zero end play, then the gasket sets the end play...

I didn't see anyone mention that you also want to be sure the gasket is the correct tissue-thin one...some aftermarket gaskets are two or three times thicker than they should be, and that extra endplay causes low pressure at hot-idle.

[Piledriver]

Yep, the right one should compress to about .004", its almost see-through soaked in oil.

[66NCVW]

UPDATE: Thanks for the tips!! I pulled my oil pump cover off. Scuffed it over glass with wet 100 a few times. Removed seemingly thick cover to pump housing gasket and replaced with sealant. Oil pressure is now close to 20psi at warm idle. I'm draining the 20/50 out of it tomorrow and putting in rotella 30 or 15/40.

[Marc]

Sounds like you've found/fixed the problem.

If sealant is used on the pump cover gasket it should be applied extremely sparingly and only around the perimeter - any excess that clogs the return groove in the pump body can actually make leakage worse.

[Piledriver]

UPDATE: Thanks for the tips!! I pulled my oil pump cover off. Scuffed it over glass with wet 100 a few times. Removed seemingly thick cover to pump housing gasket and replaced with sealant. Oil pressure is now close to 20psi at warm idle. I'm draining the 20/50 out of it tomorrow and putting in rotella 30 or 15/40.

Cool that fixed it, but for a turbo motor I would strongly suggest the 5W40 Rotella T6 or Mobil1 5W-40 Turbo Diesel Truck (NOT the "Truck and SUV" garbage) TDT is Delvac1 in a smaller bottle.

They have dropped the ZDDP to 800ppm in the HD30/ HD40 "T1" oils, if you have dual springs or even HD singles it may not end well.
ZDDP is marginal in the T3 15W40, probably ok for HD singles and mild cam.

[Tony Z]

Rimula R4X 15W40 - 1250ppm ZDDP - I had some tested last year

[Piledriver]

Rimula R4X 15W40 - 1250ppm ZDDP - I had some tested last year

That should be fine, no US EPA ruining good oil in SA.