turbotuner20v

I made a test pull on the new pulley and fresh clutch and saw some weird stuff happening with the oil pressure reading. It rises to around 55psi with rpm but then dips to 40ish. After this pull hot idle dropped to 20psi. Changed the oil and filter and cold start idle was still only 26psi. Thoughts? :/

6.0 with melling high volume/pressure pump

http://vimeo.com/m/95614840

Ls2s10

How long since the oil pump was installed? Looks the the o ring might be leaking for the pickup

turbotuner20v

I installed it on an engine stand last winter. Maybe 2-3k miles?

inspector12

Well could be the bypass lifting too! Gets weaker over time and heat cycles. My experience has been a big Change in oil pressure with no other changes. Bearing issue. But cutting the filter open will eliminate that as a possibility. Those Orings usually good from the start or not most of the time. I would be looking at the bypass or a bearing issue my first two guesses. GL Jeff! Hope it's the bypass , Oring though.

turbotuner20v

Me too, I'll pick up a cutter today and check the filter

slow ride

I wonder if all the clutch issues have taken there toll on the thrust. See if you can check endplay also.

ajrothm

+1...

5 Liter Eater

Agreed. Bypass valve sticking or bearing issue. Hopefully not the latter.

turbotuner20v

Yea, if it turns out to be the thrust bearing that went out, that's going to be the first suspect. I've heard about this issue more with torque converters, but I'd imagine constant pressure against the clutch will cause additional wear on the thrust.

turbotuner20v

Waiting to get off work to cut this filter is killing me....

In the meantime help me think this bypass thing through w/ the video from the first post...

The bypass is designed to stay closed using spring pressure that can overcome the oil pressure, so at low rpm and low pressure it should be totally closed. As the oil pressure increases, it's designed to open up and let oil flow through it. So at 7,000 rpm the bypass would likely be 100% open either way. Since my oil pressure is fluctuating downward at high rpm, would this rule out the bypass?

turbotuner20v

Here's the filter material... seems ok to me, but I don't know exactly what I'm looking for, so I took a ton of pics of both sides of the filter

inspector12

pictures are hard to see anything in so if theres nothing, then thats a real good thing. The thing about the bypass valves Ive seen the stick open and just from driving or repeated startups them go back to normal. Guessing the trash or what ever eventually gets out etc... But really no need to guess any more I guess I would either put a manual guage on it or change the sending unit to confirm reading. Then if that checks out start by pulling front cover to check oil pump and Oring situation. And probably be prepared to just replace the pump if I didn't find anything just to so you have some piece of mind.

inspector12

Filters will usually have a lot of flakes of bearing material usually silver and copper colors. Like the size of pepper all the way to larger flakes depending on how bad it is along. It will get worse over time if something did happen. GL! On another note, I have sucked the pan dry back in the day with a ported stock pump so I'm guessing thats possible now as well. Check oil level and maybe add a quart so see if it quits doing it. Could be not returning to the pan fast enough etc...

turbotuner20v

I see a few small flakes of red in the filter, but it's hard to see anything else. Unless it's still coated in oil, there is no silver dust or anything.

Any idea what red flakes could be?

I may just start it up today and take a quick spin around the block to make sure it's still low. Then look into the sensor and pump.

5 Liter Eater

It looks good to me. If you had a bearing problem large enough to make oil pressure fluctuate then you'd have glitter er'where.

When my bypass failed it stuck completely open, zero oil pressure. It was still stuck open when I took the pump off. There were burrs at the end of the bore the bypass piston rides in that eventually scored the piston which got hungup. I haven't watched the video but I could see yours hanging and then re-seating causing the fluctuation.

realcanuk

If bearings wiped out, filter would be full of metal.

Curious why high volume / high pressure pump.
I know many run the high volume.... and some the high pressure like myself, but didn't know could run both.

turbotuner20v

I'd just picture having really high or normal oil pressure at high rpm if it was stuck. Because it would either be stuck closed (super high pressure at max rpm) or stuck open (normal max rpm pressure)

And with 26psi cold idle it'd have to be stuck in the middle or I'd be at zero

5 Liter Eater

I've never seen them stick closed. I agree, if this is your issue it seems to be hanging up in the middle somewhere. Like you said, just throw some fresh oil in it and drive it around and keep an eye on the pressure.

turbotuner20v

It's just a high volume with the stiffer spring that comes with the kit. You can install with either spring.

realcanuk

Ok.. got it. Thought is was something different.

I run the high pressure, normal volume one.

Not that any of this is related to the issue.... just curious.

I would also run it while keeping an eye on it with fresh oil and filter. Maybe even try to put a mechanical gauge on to rule out an issue with the gauge or circuit.

What oil and filter are you running ?