Oil Pressure gauge like speedometer ?

[easternguy2005]

Read in the oil education area about 10lbs/1K rpm is a good rule of thumb. Was running 10/30 castrol and it's ~5lbs on gauge at idle. It can idle like that, perfect idle, no valve noise at all. The most I can get is 25 psi according to the gauge.

Switched to 5/20 castrol and same results.

I would expect some valve noise but none and there's oil up there....leave the cap off and there's oil in there moving. Has new oil pressure sensor.


Are all these stock gauges (boost, oil, temp) just that inaccurate ?

What kind of variance are we looking at ?

 

[hvyman]

cold or hot? what is it hot at idle and with the rpms up a lil? the spec is something like 5psi at idle hot and around 40psi max with rpms up

 

[jdub]

Not usually that inaccurate...5W-20 huh? Gutsy move Mav
(typically the lowest I would use is a 0W-30)

Oil pressure (warm) should be 36-71 psi...your idle pressure is normal. You really don't want to use different weight oils to increase/decrease pressure.

I would check the oil cooler circuit...the relief valve in the stock filter head feeding it is suppose to actuate at ~40 psi, sending oil to the cooler. If it's stuck open or if the spring is weak, oil will flow to the cooler earlier than designed and effectively act as a pressure leak.

 

[easternguy2005]

Sorry

At cold it will show 15 psi at idle. Rides to about 25 psi at 3K rpm.

Bold move indeed on the oil weight I agree. The Castrol lighter weights always breakdown faster. Did it to weigh out any performance gain and there wasn't any. Till I move back to 10-30 I'll be biting nails I feel.

Looking to find that pressure valve but nobody's screaming replace gauge.

 

[jdub]

A 5W-20 might be a good choice for the winter if you live in a cold climate, but generally all you would see is perhaps a increase in gas mileage. The 7M was designed for a 30W multigrade...I would stick with that at the lowest 1st number (0w or 5W) you can get. As long as you don't run the car too hard or take it to the track, you should be fine with the 5W-20.

Let the engine warm up at idle and feel the oil cooler. If it's warm, the cooler relief valve is opening too early.

Might be a good time to make the jump to a full flow, thermostat controlled cooler circuit
http://www.supramania.com/forums/showthread.php?t=62838

 

[easternguy2005]

I'm going to feel the oil cooler as you suggest and read that section.

Thanks !

Going back to 10-30

 

[grimreaper]

To add, setup a mirror or a friend and pull the cooler line hose off and put it in a bucket. slowly increase the rpms and see at what psi its starts dumping oil. Mine did at 20psi, although not full flow. I shimmed it initially which helped but still had bleed off at anything over 20psi. Now the pos valve is blocked shut with a filter adapter to a full flow setup

 

[easternguy2005]

Don't run anything under 30 - Blowing blue smoke within 100 miles without driving it excessively hard - pretty sure the turbo didn't care for this foolishness. Should have changed it right away.

 

[jdub]

Did you check the cooler circuit for when the relief valve is opening per the suggestions above?

 

[easternguy2005]

No didn't check the oil cooler. But since the turbo is out I notice that the huge bolt which holds the "oil filter screw on part" was loose. I tightened the bolt a 1/4 revolution by hand. I was the one that tightened that onto the block and think there's a big o ring back there. I remember tightening it because its a pretty odd looking bolt. The turbo to exhaust manifold bolts weren't as tight as they could have been as well. Those manifold to head bolts will scare a person about tightening too much !

I'll have to take a look at what the heck is going on there with the "spring" that regulates the oil pressure on there.

Of course I kick myself for not taking a feel of that while it was running. Now that it's apart it may not be so easy to determine.

 

[jdub]

Yeah, now that the turbo is off it will be easy to remove the filter housing. Might be a good idea just to get a new cooler relief spring from the Dealer...it can't be very expensive and it's easy to replace.

 

[grimreaper]

A new filter head to block gasket as well. #96732-31070, cost me $7-8 OTD at local dealership

The spring jdub speaks of is #15132-21010 seen here CLICK
Shouldnt be but a few bucks as well. Im surprised you didnt have an oil leak if the bolt was that loose

 

[jdub]

Get a new crush washer too...part #90430-20010 in the pic. Same for the crush washer holding the spring in.

Make sure you clean any deposits on the little piston and in the tube it fits in.