dreygata

Ok, after much hair pulling, I believe my low oil pressure issue is due to my OPRV binding since I never aligned my housing.
Quick recap:
Car is an 87 924S
Full engine rebuild and clean (passages are clear, new rod bearings and crank, new seals all the way around)
No noticeable crack on oil pickup tube
Crank bolt torqued to 155 ft-lbs
Pressure at idle sits just below/at 1 bar
poured oil down the oil filter hole, pressure went up to normal, then dropped after a bit
replaced sender unit with new FAE one

Given that I never heard about aligning the cooler housing until now (must have missed that part), I believe that's my issue. I'm trying to not shell out $40-$60 + shipping on a one time use part, and I don't have access to a metal lathe, so is there a way I could borrow/rent a tool from someone? I'd be eternally grateful.

There's a small chance I could get someone to make one out of wood. Has anyone done this before?

PaulD_944S2

Is this outside your budget?
https://www.ebay.com/itm/WPO-SPECIAL...19.m1438.l2649

931guru

fu

dreygata

Actually, the tool I need is around $20 since i determined I had the early one piece OPRV, so it's better for me now.
And you are way off on your engine rebuild assessment. It's about $700-$800 (DIY) because I just did it.
I asked to borrow or rent a tool from someone so I could save some money if possible, since I figured this was a friendly community. Otherwise it's not an issue if I had to buy even the $60 variant.
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No need to be an *** about it.

In the meantime, I drained my coolant, pulled my oil filter, my sending unit, heat shield , the OPRV, and loosened the housing. I then carefully used the OPRV itself as a guide, making sure I could easily thread it in prior to tightening, then removing the OPRV again, and see if it still threads in easily. I'm pushing around 1.5 bar cold idle, but I need to add more oil since I lost some during the whole process (accidentally tried priming the oil pump with the oil filter off....) so I had to run to the store. I'll provide an update after I fill it.
If all seems well, I might be able to put off the tool/ be able to focus on other things until I can get one ordered/borrowed/3D printed/machined from a friend

V2Rocket

crank is torqued to 155lbft, but did you put:
- the o ring on the crank snout inside the drive gear?
- the washer against the o ring, behind the timing belt drive gear?
- the crank bolt washer the right way around (flat side towards engine, conical side facing front of car)?

what viscosity oil are you using?

dreygata

Yes to all of those. I was pretty **** about most things, though obviously I forgot the alignment step on the cooler.
Oil is STP SAE 20W-50, oil is showing right in the middle of the dipstick.
Car went to 2 bar, then idles around 1.5 bar. Outside temp is 57F.
Since doing the non-pin OPRV alignment of the oil cooler housing, the engine has quieted down, so it's an improvement, not doesn't give me a warm and fuzzy yet. The OPRV is the early single piece with a new green o ring. I have not replaced the internal one (I'm guessing you just pull it apart?). The OPRV seems to move without issue, but this is the only one I've ever dealt with so I don't know how stiff or compliant the movement should be.

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dreygata

Increased RPMs to 5000 rpm, around 2.5 bar, then idled around 1.5 bar. Shut car off, waited a couple minutes. Started car back up, idled at 1.5 bar, increased to 5000rpm, around 3 bar, then idled around 1 bar with the oil light coming on

dreygata

Ugh, now it's idling around 1 bar again. I don't know what's going on unless the oprv is still finding a way to bind up.
I'm going to order the alignment tool and fix the alignment of the oil cooler housing for certain.
Where is a good resource for the oprv internal o ring? Pelican parts? What's the part number for it?

This car is getting infuriating since I've only driven it 2 months out of the 14 months I've owned it...

V2Rocket

yeah, at that sort of outdoor temperature with 20W50 the gauge should be pegged at 5bar when cold idling.
o-rings...
http://forums.pelicanparts.com/porsc...e-o-rings.html

dreygata

Thanks for the thread, though it was a bit confusing with the person trying and failing to get his OPRV reassembled, and then never giving a final update.
I'm guessing the 944online 999 707 146 40 o ring is the correct one for what I need. Sometime this weekend or next week (I need to write a report for school, so I've banned mechanical tinkering for the week), I'll pull apart the valve and see if the o ring remains intact for comparison, though I'm not hopeful since the technical bulletin states that it will be destroyed in the process.

I'll report whether or not it will work. I went ahead and ordered the early retrofit alignment pin off ebay for $20, so we'll see how that goes. Honestly, this is probably better so I can focus on my school, lol.

V2Rocket

to erase any doubt, if you haven't already, call Ian @ 944online.
his knowledge of these cars and their parts are second to none.

dreygata

I will absolutely do that. I need to order the power steering plug from them anyways, so I'd be glad to give them my business.

Tiger03447

Don't be disheartened yet, young owner..I've been working on mine for over 5 years now and haven't EVER driven it..Hopefully this will change soon. I pulled it out of a field where it had sat for over 10 years...mine is a kind of a "chicken thing" just gotta keep pecking at it..

dreygata

Long time with no post. I called 944 online, and they said that it's generally not worth replacing the internal OPRV o-ring, as they, more often than not, don't go back together correctly. I pulled the OPRV, and tested both ends for movement, and everything seems to move well. The lower end moves freely and snaps back fine with no hang ups, and the upper end near the thread moves fine as well, though it seems to be a much stiffer spring. I also got the tool for my specific OPRV to check for my alignment... and it goes into the oil cooler housing with zero resistance . So that being the issue seems out. Honestly, for sanity sake, I'll probably realign the oil cooler housing anyways, but with using the tool, just to fully remove that as a variable.
I'm guessing, at this point, I need to leave the OPRV out and see if oil comes out of the hole. I'm hoping that will tell me if the problem is with my oil pickup tube? I'm already not looking forward to pulling the pan off, as it took me long enough to get my steering aligned, and with it being colder and darker out, it's not nearly as fun working on this.
Any other suggestions?

dreygata

OK, so I finally got around to cranking the engine without the OPRV in, and nothing is coming out. Prior to this, I retorqued my crankshaft bolt to a little over 155 ft/lbs.
At this point, I'm guessing something is wrong with my pickup tube or the oil pump itself. Since the oil pumps seem to be pretty robust, I'm guessing it's the pickup tube?
Any thoughts?