oil pressure relief valve

[mueller944s2]

Anyone know where this thing is? I need to check it, I'm afraid it's stuck and I'm praying it's not near the oil pump. Do I need to pull off the belts and everything else in the front of the engine or is it simple to get to?

[krystar]

it's on the lower pass side of the engine. near the oil pressure sender. from the outside, it's just a big hex nut. u don't need to pull off belts to get to it.

[aj951]

It's below the Oil Filter near the sending unit. I can't remember the size (19mm I think) Hex head. It's easy access.

A.J.

[mueller944s2]

And if I pull it out to see if it's stuck oil won't come pouring out or should the oil be drained first?

[krystar]

there'll definitely be a bit of oil coming out, but it's above the oil level in the pan, so it's not going to be draining from the sump. just catch clean up with a rag

[FransB85]

What symptoms led you to believe it is stuck? Did your filter blow off the housing (OPRV stuck closed) or did your pressure drop (OPRV stuck open)? Also, did it happen while you were driving?
Hope for you nothing serious in terms of damage resulted from this!
These valves are rediculously expensive by the way...

[John_AZ]

I think you have other problems:

http://forums.pelicanparts.com/porsche-924-944-968-technical-forum/706708-broken-s2.html

John

[lwbfl]

Interesting that his came up today. Last night I noticed that at idle my pressure was down to 1.5. I consulted the manual that I got yesterday from a member of this site and it said it was OK even if the light came on at idle! No light but I've been driving my car now for weeks and it's always had 3 bar at idle. I did recently change the oil and filter but it's been two weeks and this just started yesterday. Today was the same thing. Now my gauges are not reliable, all but the fuel gauge is effected by turning on / off electrical devices so I'm scared to drive it now. How do I check the true oil pressure and if this is correct what do I need to check next?

[kfanazini]

What weight oil and filter did you use?

Originally Posted by lwbfl

Interesting that his came up today. Last night I noticed that at idle my pressure was down to 1.5. I consulted the manual that I got yesterday from a member of this site and it said it was OK even if the light came on at idle! No light but I've been driving my car now for weeks and it's always had 3 bar at idle. I did recently change the oil and filter but it's been two weeks and this just started yesterday. Today was the same thing. Now my gauges are not reliable, all but the fuel gauge is effected by turning on / off electrical devices so I'm scared to drive it now. How do I check the true oil pressure and if this is correct what do I need to check next?

[John_AZ]

+1^^

and the recent "fix" was to check your oil pressure sender wires for tight connection.

John

[FransB85]

If all your gauges are affected by turning on/off of other electric devices, perhaps you should also check the ground connections of the inst. cluster/other dash components.

But you'll probably want to concentrate on verifying your oil pressure first

[lwbfl]

I used Castrol 10W-30 and an STP filter. I had to order a K&N as nobody had one in stock around here.

Jpn, not sure if that was meant for me but I haven't checked any wires until now.

Yes, checking the grounds will be next but OEL pressure is definitely first.

[John_AZ]

Originally Posted by lwbfl

I used Castrol 10W-30 and an STP filter. I had to order a K&N as nobody had one in stock around here.

Jpn, not sure if that was meant for me but I haven't checked any wires until now.

Yes, checking the grounds will be next but OEL pressure is definitely first.

lwbfl,
When you changed your oil a couple of weeks ago, why did you go with 10W-30?
http://forums.pelicanparts.com/6953271-post1.html
BTW, the oil light flashes when you are low on oil-6 quarts needed to fill- top of dip stick- or oil light will flash.

In the manual I linked for you, there is an oil chart.
http://forums.pelicanparts.com/6992553-post8.html

What did the PO previous owner use?

John

[lwbfl]

Originally Posted by John_AZ

lwbfl,
When you changed your oil a couple of weeks ago, why did you go with 10W-30?
http://forums.pelicanparts.com/6953271-post1.html
BTW, the oil light flashes when you are low on oil-6 quarts needed to fill- top of dip stick- or oil light will flash.

In the manual I linked for you, there is an oil chart.
http://forums.pelicanparts.com/6992553-post8.html

What did the PO previous owner use?

John

Thanks, I figured the flashing light out - guess it takes a while to fill that filter up on these things. I used 10W-30 because I was too lazy to go 20 miles to the nearest store when my local one was out of 20W-50. The previous owner was having his oil changed and doesn't know other than Valvoline. Thanks again for the manual, it's been a great source of knowledge for my new toy!

[mueller944s2]

The story was I was doing a lot of long distance driving and at a stoplight (luckily next to my house) it started making a knocking noise and the oil pressure dropped to 1. I towed it home and found the oil was really low. I check it persistantly but this was weird, it never drinks that much. I pulled off the belt cover and everything is good in there. Pulled off the valve cover and chain tensioner and valve springs are good. Changed the oil and there was a tiny bit of copper at the bottom, but not much at all (bearings). I was told a lifter might've collapsed so I ran it for 5 minutes and the knocking got a little better but not much. The oil pressure cold is 4 which is lower than normal and I was also told that the relief valve might be stuck which would cause the low oil pressure and keep a lifter from getting enough oil. Using a stethoscope I can't hear anything inside the engine, and the sound is coming from the head area.

[gtroth]

Originally Posted by lwbfl

Thanks, I figured the flashing light out - guess it takes a while to fill that filter up on these things. I used 10W-30 because I was too lazy to go 20 miles to the nearest store when my local one was out of 20W-50. The previous owner was having his oil changed and doesn't know other than Valvoline. Thanks again for the manual, it's been a great source of knowledge for my new toy!

Perhaps the STP filter does not have the check valve like the Mahle's do? Why not just use a Mahle?

[John_AZ]

lwbfl,

Stick with 20-50 Castrol GTX or Valvoline RO 20-50 in the Florida Panhandle -warm & hot. Better for the high mileage '87 engine bearings with more ZDDP.

John

[gtroth]

Originally Posted by mueller944s2

The story was I was doing a lot of long distance driving and at a stoplight (luckily next to my house) it started making a knocking noise and the oil pressure dropped to 1. I towed it home and found the oil was really low. I check it persistantly but this was weird, it never drinks that much. I pulled off the belt cover and everything is good in there. Pulled off the valve cover and chain tensioner and valve springs are good. Changed the oil and there was a tiny bit of copper at the bottom, but not much at all (bearings). I was told a lifter might've collapsed so I ran it for 5 minutes and the knocking got a little better but not much. The oil pressure cold is 4 which is lower than normal and I was also told that the relief valve might be stuck which would cause the low oil pressure and keep a lifter from getting enough oil. Using a stethoscope I can't hear anything inside the engine, and the sound is coming from the head area.

Oil pressure dropping to 1 could have been just the engine almost stalling for any number of reasons, no?
But you have to find your missing oil. How low was it? I think you should look for it in the coolant (milkshake).

I think the OPRV ordinarily fails to high pressure (anyone confirm?). It's next to the oil pressure sender and uses a 24mm socket. You'll need a new crush washer for it if you remove it, and I'd replace the two o-rings as long as it is out. Of course if you have oil in your coolant, you'll be resealing the oil cooler and its housing...

[mueller944s2]

Originally Posted by gtroth

Oil pressure dropping to 1 could have been just the engine almost stalling for any number of reasons, no?
But you have to find your missing oil. How low was it? I think you should look for it in the coolant (milkshake).

I think the OPRV ordinarily fails to high pressure (anyone confirm?). It's next to the oil pressure sender and uses a 24mm socket. You'll need a new crush washer for it if you remove it, and I'd replace the two o-rings as long as it is out. Of course if you have oil in your coolant, you'll be resealing the oil cooler and its housing...

Well the pressure is running a little lower all the time now. The oil was at the bottom of the stick, low mark. No oil in the coolant. Engine is also 2 years old, complete rebuild.

[gtroth]

Ok. Cold oil pressure is kind of meaningless. Did fully warm idle pressure drop consistently with no explanation (such as going from -50 to -30 weight oil))?
Did the rebuild include sealing the oil cooler and replacing seals in the OPRV?
And to be clear, which oil light blinked on, pressure or level?