Gents - i agree with you regarding the points. Yes I think I’m confusing matter with my 993 manual. Does anyone happen to have 964 manual that has oiling diagram?

Scott - Do u have a gt3 oil pump in yours? You said u showed about 80 psi where I was showing the 120.

Actually 965 oil diagram...

I have a 996 style Porsche Motorsports GT3 Cup oil pump in my race engine.

Thanks Scott... so do I. Shot that theory.

When you convert to the oil filter setup, there is some kind of shim that has to be put in place somewhere otherwise oil pressure is too low. I don't know where this shim goes or how thick it needs to be....I have just heard about it. Maybe the shim in your engine is too thick.....or too thin??

I pulled the 964 pet (pic below) and what I found interesting is they do NOT measure oil pressure on the 965 (turbo) on the large cover (part 33 in this pic). they do it using adapter 53 on the port right above the oil pressure regulating piston. ...and replace the pressure sensor on part 33 with a temp sensor (parts 49,50,52).

Scott - Not sure what shim you're mentioning, however, there is a spacer ring (13A) that was added on 964's. However, it is listed for all 964's, not just turbo. It looks as it was a late add as it's part 13A. I do have this spacer in my motor. ...also, just to confirm, you're measuring pressure on pic below on part 33 and getting 80 psi at that point.

The only other difference I can see is I'm running the shorter 993 oil filter and not the taller (944 part number filter) as shown in the 964 pet for the 965. ...which I was not aware of until last night when I was reviewing pet.


http://forums.pelicanparts.com/uploa...1597577667.jpg

Did more investigation this weekend and beginning to make conclusions here:

1. As some have suggested point 1 is pre-filter and point 10 post (using first pic I posted). I took oil filter off and outlet of filter (center part) seems to align with point 10.

2. I took pressure regulating spring and piston out and I can look up into hole and see the bottom of the brass pressure sender i have screwed in a tapped plug at point 10.

3. Now my only question is what appears to be pretty big pressure drop across oil filter at around 30psi. However, i have the larger 944 filter on the way and will replace it with the smaller 993 filter I have. Maybe that's just the extra power of the gt3 oil pump. I did see on the 944 filter specs that the by pass valve has a range of 25-35psi.

http://forums.pelicanparts.com/uploa...1597664317.jpg


http://forums.pelicanparts.com/uploa...1597664629.JPG

Joe - you first said that you got a lower pressure reading at point 10 than you got at point 1. This seemed wierd, as it appeared that while point 10 is going to show pressure as reduced by the pressure reducing system, Point 1 ought also to show regulated, rather than raw, pressure.

But perhaps in the 964 or 993 system this is different? Drillings are different in this area, so a cap is all that is needed over the former thermostat cavity? In your picture with the red line, you can see over to the left where the oil passage from the pump turns and heads up to the upper part of the engine. In earlier cases that passage ends/feeds the bottom of the cavity which held the thermostat. That is going to be, at that point, unregulated pressure. If that pressure makes its way up to the top cover with its pressure gauge, before being sent to the pressure regulating passage, maybe that mystery is solved? Or maybe not. A regulator anywhere in a system (absent a one way valve) ought to regulate the pressure everywhere?

I too have struggled with trying to map out where the oil goes in the 911 engine case. You certainly need to look at the passages in a disassembled case and then it makes more sense. Also, that 993 diagram is nice to see where oil generally goes. But being that the diagram is flat/two-dimensional, it doesn't tell you the whole story and thus can be misleading.

The old school three-dimensional diagram is best to see where all the oil passages go and how some of them intersect.

http://forums.pelicanparts.com/uploa...1597788240.jpg

What's noteworthy here in this picture is the location of the oil warning light location #10 (in the first post on this thread) and you can see how that column is fed from two locations, depending on the position of the thermostat. In the cold condition the column is fed from the upper port in the thermostat cavity. In the hot condition the column is fed from the return side of the oil cooler/oil filter portion of the case.

So in the case of the 993 or 965 engine case, it is AFTER the filter since the thermostat cavity insert blocks what would be the upper/cold port. In a 964 case, the thermostat cavity has only a cap and has no provision or reason to shape/direct oil flow since there's no oil cooler or oil filter present. The cavity simply fills up and oil goes out the side port to send oil onward to the column where the pressure release valve is located down below, and "around the corner" is the feed to the crank main bearings

Yes that oil pressure relief spacer is a mystery to me about how it came to be implemented. I too have heard that if you run a larger pump like the 964 pump in an older case, which I did do for a short (very short) time, you need that spacer or you will see lower pressure. I saw only 60 psi at high rpms and I was accustomed to seeing 80 psi on my dash mounted (in the factory dash clock location) VDO mechanical oil pressure gauge. Incidentally that oil pressure gauge feed line was connected to Point 10 as we continue to call it. Anyhow, I find this pressure relief spacer odd because a big pump like the 930 pump is used in the old case with no pressure relief spacer needed. Only some clearancing of the case webs is needed for the 930 pump to be a direct drop-in installation.

Thanks, Kevin. I hadn't realized the 964s (some of them, anyway) didn't have the oil cooler/filter in and out ports machined open.

This must mean that my 935 style insert replacing the thermostat and sending the oil through an oil filter sends full, not yet regulated, pressure through the filter. Never had an issue with my Station 1 filter, though - it is pretty stout, nor the -12 lines and fittings I use to remote mount the filter. All up to whatever pressure shows up.

And the 993 has some kind of insert, not just a cap.

Thanks Kevin... that 3d pic helps a lot.

oil pressure puzzle
 

This experiment was to get as much flushing pressure to the main longitudinal gallery as possible. The gadget in my hand I made to block off all but the access to the longitudinal gallery that feeds the crank. It fits into the oil pressure sensor bore next the thermostat cavity. Doing all of this with the stoppers and such gave me a little more info on what the oil wants to do when it enters the block. This is part of my test to see if I can successfully flush the complete oil system on my track car. I have done 1 weekend with my second motor with flushed out coolers and lines. I have a serviceable oil filter in first position and checked it after every session. Cut open the 2nd position filter after the weekend and all squeaky clean. Hope the pics aid instead of confuse. Bobhttp://forums.pelicanparts.com/uploa...1597845351.jpg
http://forums.pelicanparts.com/uploa...1597845383.jpg

Should have added this for clarity or maybe redundancy. As seen in KTLs diagram, the pressure side oil comes verticaly up into the thermostat cavity which serves as a hub or intersection. From there it can enter a short horizontal gallery that intersects a vertical gallery, by pass valve at the bottom and oil pressure switch at the top. It can also exit into another short horizontal gallery that will serve the oil cooler. Depending on what is in the thermostat cavity, a thermostat, diverter or nothing, the oil eventually gets to the long gallery running longitudinally above the case webbs. My picture does not show it well, but it is there. From that long gallery, oil is delivered to the main bearings through the webbing. The through bolt holes are exposed to this flood as well. Then into the bottom of the case where it is scavenged by the pump to the main filter, then front coolers and last back into the tank flowing from there to the pressure side of the pump.

All I know is that Hose #12 in the diagram has the hardest to reach hose clamp of any there are.

...so have oil pressure data into the oil filter with the taller "proper" filter and it's basically the same as shorter one. Maybe a few psi lower at high rpm. What is interesting is the filter is running at some level of bypass at anything higher than around 5k rpm using 80 psi after fitler on regulator piston.

Totally shows to keep any sort of failure debris (or other for that matter) out of motor you need to have filter on the line going to coolers (or on suction to pump). I put one in (40 micron canton) after I spun a bearing on a motor on line going to my coolers.


http://forums.pelicanparts.com/uploa...1599159606.JPG

http://forums.pelicanparts.com/uploa...1599159606.JPG