Tboy's EPIC 9-5 Oil Pressure Thread - The Saab Link Forums

Go Back   The Saab Link Forums > Saab 9-5 '98-'09 Forum > Car Problems? 9-5 Only

Car Problems? 9-5 Only If you're experiencing problems with your 9-5, post your question in here. CEL Code or GTFO!

SaabLink.net is the premier Saab Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools
Old 05-19-2017, 09:56 AM   #1
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Tboy's EPIC 9-5 Oil Pressure Thread

A little background and I will try to keep this short for those of you with limited attention span!


Bought a 2000 9-5 Aero 5MT in March of 2014 with 252,145 miles! It was a wonderful example but had two major issues. One was it would not go into reverse (bent shift fork I believe) and the other is there was a hole in the timing cover from a water pump pulley when it failed (so it leaked oil there pretty good). If you've worked on these much, you know if you need to take the trans out AND the front cover, you might as well pull them both! So I did that and decided to rebuild the engine. The rebuild went well, crank polished, bores honed, head refreshed and all new wear parts including balance shaft bushings. I did NOT replace the oil pump since the wear on the engine seemed so small (mistake? maybe maybe not!). Instead I asked a friend to tig up the hole and he did so wonderfully, and you would not even know there was one.

Motor goes back together and I throw on there an iequus oil gauge. It has an output to run a dummy light as well as the gauge. I did not hook up the gauge but did hook up the dummy light.

Fast forward 24,548 miles or so. Never had any issues and the car ran great. Then all of a sudden I get the dreaded oil light flicker!!! I change the oil and filter (due anyway) and the problem persists. So I park the car and decide I better get that gauge installed. Once installed I start it up and let it idle, Oil pressure starts out great, (60-70 psi) and gradually tapers down to 0!! No crap, ZERO. I'm starting to think that I might have made a huge mistake by not replacing that oil pump and cover.
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 05-19-2017, 09:58 AM   #2
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
So here is what I did:

First thing I did was to change the oil thermostat. I thought that perhaps I was cooking the oil as it warmed up. I didn't have a good way to measure this, but I am a parts hoarder!

I was reading this article by Chuck Andrews, and he showed a picture of several different oil thermostats. I just happen to have a thermostat from a B234 from when I did that swap on my first 9-5! So I swap the 225 degree B235 thermostat for the 167 degree B234 thermostat.


No change!

So I take out the pressure relief valve. Hoping it would be stuck in there I remove the bottom nut and everything nicely drops right out, just as clean as the day I put it in there 25k miles ago. But I don't stop at inspection, I go ahead and shim it two hardware store washers.

No change!
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 10:01 AM   #3
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Oil Pump Gear Set

Next I try a new oil pump gear-set. Years ago when I dealt with a similar oil pressure issue in my first 9-5 I remember reading that some manufacturing issues had caused some timing covers (oil pump housings) to be out of spec. So when I built this motor I thought "if it ain't broke...." and re-used the original timing cover and gear set.

Saab is not terribly good at giving any measurements to inspect the oil pump either.

According to WIS, they spec "End float between oil pump rotor and housing" and spec 0.03 to 0.08 mm. No ilustration is given, and clearly there are more measurements than that! So out comes my manual for my Honda Civic! The 1.5L civic uses the same oil pump design, and slightly smaller. I am a big Civic fan, and think that the D15B7 motor is a fine little machine, it is just not much to brag about! Honda is much more detailed with three measurements:

Radial Clearance on Pump Rotor:

This is the clearance between the inner and outer rotor lobes. It is easy to understand that if the gap is too large, the lobes seal off as they close and oil will just run past into the next open lobe. It seems to me this would be the most important measure and Saab does not even check it! It turns out for me, my OLD (276k miles now) gearset is actually better than the new one i bought!! I measured with feeler gauges somewhere between .14 mm and .15 mm with the old set, and .15 mm with the new set! This is slightly out of Hondas "new" spec, but well within their sevice limit of .2 mm.

Axial Clearance:

I think this is what Saab means by "End float".
This was extremely hard to measure in the car but I did my best. Because of the pump design you need some sort of straight edge, but it is really short. I cut a piece of angle aluminum and used it to get my feeler gauges in there.

I am an Engineer by trade and I am very familiar with high precision measurment and I will declare this was not! An aluminum piece of angle is not a straitedge but it was the best I could do. Again, my old gear-set was better than the new! I measured somewhere between 0.08 mm to 0.09 mm with the new, and 0.08 mm with the old. Again, this is right on Honda's "new" spec of 0.08 mm but well below the service limit of 0.15 mm.

Radial Clearance (Housing to outer rotor):

This was easy to measure, just start sticking you feeler gauges in the gap. Again my old set was better than the new pump! I measured 0.25 mm to 0.28 mm with the new set, and 0.18 mm to 0.20 mm with the old set. This was because the OD of my old gearset was bigger than the OD of the new gearset! I measured this is digial calipers (not the best tool for this but what I had) and the OD of the new outer gear was 89.74 mm and the OD of the old gear was 89.82 mm.

Honda's spec is tight here, 0.18 mm is the upper limit for "new", but the service limit is right on top of that at 0.20 mm. So I am right on the edge here.

Pump scoring: the only significant scoring I have is on the pump cover, shown here:


Honda says" "Inspect both rotors and pump housing for scoring or other damage. Replace parts if necessary". That's not much help!

Since it is easy to swap the gear-set, I do it anyway and there is no change. I think at some point I will change the pump cover for good measure. But my conclusion here is my pump is NOT shot, and should be producing some oil flow!
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
 
Old 05-19-2017, 10:03 AM   #4
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Time to drop the pan!

So I decide to see if I have a sludge issue. I have some doubt, I did not mess with the PVC system on this motor. Again, if it ain't broke..... I reasoned at the time that it had 250k miles on it! Aero's somewhat avoided sludge since factory spec was full syn oil, and in general the owners were more enthusiasts and meticouous about oil changes. This certainly seemed to be the case with mine!

Off comes the oil pan and no significant accumulation is found:


There was some gunk in there but it was not enough to cause zero oil pressure. I clean and re-assemble everything. I kicked myself because I did not remove any bearing caps. I had planned to, but I had to stop work for a couple days, and when I came back forgot and went straight to re-assembly. I kinda regret that but I figured 25K miles! And I checked EVERY bearing on assembly. Here are a couple of notes I took when I assembled the motor:

Very light scuffing on the cylinder walls. This was the worst. Crosshatch still clear:


This was the worst bearing clearance:

This is a rod bearing, factory spec is .020 to .068
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 10:05 AM   #5
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Time to think about that oil gauge!

So I started looking closely at that oil gauge! I pulled the starter off and removed the sender, and then took the gauge out of the car. I wanted to know for certain what pressures things were happening, so I made a little test setup. I purchased a Shop Oil Pressure Gauge from Harbor Freight. It is not the best, but seems to agree with the gauge on my compressor. I wish I had something that was calibrated!! I should mention that I did all this testing with AIR. Air is a fluid too, and I reason that alot of aftermarket oil pressure sensors are actually measuring compressed air in an engine. Think about a mechanical oil pressure gauge. You plumb that in with several feet of nylon tubing. Does oil travel down the tube? Only if you have a leak, or somewhere the oil can displace the air to! So in normal operation, the oil pushes on the air, the air compresses to a certain pressure (the same pressure the oil is pushing with) and the gauge measures air pressure.

I plumbed up a little rig:

There on one side is the shop gauge (reference) and on the other side is a factory pressure switch. The factory switch is M14 X 1.5 thread and I noticed that 1/2 pex tubing was about the same diameter. I was able to forcibly thread the factory fitting into a section of PEX, and then the pex was fitted onto a 1/2 fitting. This was not perfect and had a little leak, but I have an 80 GAL Compressor so a little leakage was acceptable (ie it would not drain the tank). I had an old sender which I had removed from a car (possibly this one but I can't be sure) and it switched on at 4 psi! So 5 psi is "good" to this switch. I tried a brand new sender that I purchased, and it switched on at 6 psi!

WIS says: "Warning lamp comes on when oil pressure is below 0.3 - 0.55 bar" Which is 4.35 to 7.97 psi. So probably BOTH these senders are good within factory spec. My rig was not good enough to tell if the old switch (which read 4 psi) was truly good enough. But the new switch was definitely in the range.

Moral of this story: Do you feel comfortable operating an engine that is running FIVE psi!?!?! Probably should get a real gauge on that high dollar motor of yours.

So now I moved on to the aftermarket iequus gauge. I set this up in the same manner. Remember this sender has dual output, one to run the dummy light and is just a switched light like the factory sender. This is what I checked first. I found that this sender came on at 14 psi. That's almost double the factory spec, but more importantly violates the old adage "10 psi for every thousand RPM". So in my case, it is possible that the light was coming on even when I had "enough" oil for idling.

Now time to check the gauge. I grabbed a 12V wall wart, and hooked up the gauge. I was surprised to see that this gauge was not accurate. Disclaimer, the aftermarket gauge has very few markings, and even some "non-standard" markings. For instance, the gauge has 0, 25, 50, 75, and 100. That means the half way ticks are 12.5, 37.5, 62.5, and 87.5. So it is not really easy to interpolate the number between 12.5 and 25.


At 30 psi it read 25

At 40 psi it read 32

At 50 psi it read 47

But a couple really large errors still to be uncovered! WIS states min oil pressure is 2.5 Bar (36.25 psi) at 2000 RPM and 221 F oil. So I set my pressure to 36 PSI and read 26-28 psi from the gauge!!

So I was missing a benchmark on the car that was critical. Reading 47 psi when the pressure is 50 is not so bad but if you are trying to really see what is going on then you need a gauge with better graduation.

Finally, I set the air to 10 psi, and the iequus gauge didn't read a thing. ZERO. Plus, with a totally stead air supply, the gauge needle did bounce slightly. I had noticed this in the car, but didn't think it was the gauge. A couple of notes on this. This gauge was set up in the BEST possible solution. I checked the voltage on my power supply and it was rock steady 12.36 V. The sender was COOL, and still. Not buried on the back of a HOT engine, and not vibrating like it normally would be. Some might argue that it was because it was cool that it was off, but I argue that it was off by more than 10 PSI! I have been around precision instruments and have had to acclimate some of them for precision work. But that is when you are trying to measure .0001 (make up your own unit here) not 10!

So "In the BIN" with this gauge!
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 10:08 AM   #6
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Oil Pump musings

In my quest for knowledge, I learned a lot about oil pumps. The pump that is used in the 9-5 is a gerotor pump. It is very common in automotive. My Honda used an almost identical design! A gerotor pump always has one less lobe on the drive gear than on the driven gear. The drive gear is the center smaller gear, and in our case is driven directly off of the crankshaft. The larger gear (outer) is eccentric, meaning it does not rotate around the same axis as the driven gear. There are lots of good animations online that deal with this so I will just say that as the gears separate the oil is drawn in to the pump, and as the gears come together the oil is forced out creating flow. The pump is a constant flow pump, meaning that it draws in a specific volume of oil per lobe and pushes that same volume out. I thought a lot about what that volume is. There are better ways of measuring this, but I wanted to approximate the flow of the pump. I just took into consideration ONE gearset. In reality there is more area opened up between the two cavity's.


I measured the diameter at the bottom of the lobe.

I measured the diameter at the top of the lobe.

I measured the peak to peak of the lobes.
I measured the thickness of the gear (forgot that picture)
I created a triangle to approximate the volume in the lobe.
The volume was 343 cubic millimeters. With 15 lobes on the inner gear, for every full rotation the pump will push out 343 cubic millimeters 15 times. Or 5145 cubic millimeters. So at 1000 RPM (idle) that is 5,145,000 cubic millimeters per minute OR 1.35 Gallons per minute. And that is an approximation, there is definitely more area in that lobe than a triangle. I would "guess" this pump is probably 1.5 gal per minute at 1000 RPM. I could just not imagine where 1.5 gal per minute was going on a fresh motor! I looked at the scoring on the pump cover and thought there is no way 1.5 Gal per minute is going through those small grooves!!

****Remember this was just an approximation of just one of the gears. In reality space is created between the inner and the outer gear so the volume would be even higher!
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 10:09 AM   #7
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
New vs old oil pumps?

From the Saab 9000 to the Saab 9-5 the oil pump changed a bit. I want to talk about that some.

Then 9-5 uses a Gerotor pump. This is basically just two gears. Most gear pumps operate on the same principle. As the gears separate they draw in oil, and as they come together they force it out. The old 9000 used a crescent pump. The two are shown here, one from a B234 engine and the other from a B235. Whats the difference!?!? Not much really. As you see above the volume of the pump is determined by the cavity between the inner and outer lobes. Want more volume, make the gearset bigger! Clearly the B234 pump is larger but not significantly. So the B234 motor should have more volume. That's good for a worn engine where your are pouring most of your volume back to the sump. What about Crescent vs Gerotor? Gerotors always have one more lobe on the driven gear than the drive gear. You can see that the Crescent pump has many more lobes on the driven gear. This is beneficial to even out the flow of oil. More lobes results in a more steady flow (less lumpy). Is the B234 oil pump more expensive? You bet. Probably substantially. There is WAY more machine time in the gears themselves. In addition, the housing is more complex. In a crescent pump the clearance between the "crescent" and the gear lobe is critical. So from a manufacturing perspective Saab would have to hold tight tolerances on both the gear teeth, and the Crescent shape (on both sides). On a Gerotor, they are only concerned about the gear mesh, and likely you could theoretically mix and match gear sets to get a really good mesh. That's easier than trying to machine them all perfectly, and all the same.

Is the B234 pump better than the b235 pump? Yes, but in my opinion the difference is negligible. This is probably what saab thought when they made the changes. You could probably argue that the b234 pump is better at chopping up little pieces of junk with all the sharp teeth it has. I would agree, but it is not like a 5 mm piece of steel is fragile! And either way, there should not be little pieces of gunk floating around in your engine. Saab made that an issue with an ineffective PCV system of course. Just looking at the pump the B234 pump looks bigger, with more capacity. True, but probably this goes un-noticed until your bearings wear out. I've heard some people say they want to run their bearings on the loose side for turbo applications. I think this is complete garbage! It is just an excuse to use a worn out engine and hopefully you have an oil pump with enough umph to make up for your poor judgement or lack of ability to measure clearance.
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 10:11 AM   #8
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Oil Pressure Readings

It seems like people put their oil pressure gauges in one of three spots. The factory sending location, an oil filter sandwich, and on the banjo feeding the turbo. Let me talk about those. I think the place with the LEAST pressure is where the factory placed the sender. This location is almost last in line to get any oil. The sandwich adapter probably has the most oil pressure. This is right after the pump, and even before it passes through the filter which is a restriction. The banjo bolt to the turbo is the location Saab shows to check the oil in the WIS. You can buy a banjo bolt from glowshift that is M14 x 1.5 mm with an 1/8 NPT threaded in to the back. This is where I plan to install my next oil gauge. I'm not a fan of the sandwich adapter since the filter is not included in the reading. If by chance you got a bad filter, you might not be able to see the difference! Of course, it is also possible that the filter is so restrictive that the reading was really high! Anyhow if you pay attention and buy good brands you should be OK. I think if you were to measure the difference between the factory sender and the banjo location you would see a difference. How much? I don't know.
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 10:12 AM   #9
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Now What?!?

So I have strong evidence that the gauge is wrong, and perhaps the motor is OK! Yay. But I still want to verify. What I really want is a good oil pressure reading. For my car, I purchased a new factory sender, and will install it in the OEM location. Knowing that this specific unit I tested switches at 6 psi is a good bit of info to have. I think I will bury that back there and forget about it. I also purchased the aforementioned glowshift banjo adapter. I plan to put that on the oil filter housing, on the same line that feeds the Turbo. I think this is a really good location to put a temperature sending unit as well as this is right after the oil is filtered, and cooled if the thermostat is open. If your readings are from a sandwich unit, you will get readings before the oil is filtered or cooled. I think that would be worst case for the temperature but doesn't really reflect what the engine is being fed.
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 10:19 AM   #10
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Shop Gauge Install and Results

So last night I put the glowshift banjo adapter in place of the stock banjo and installed the gauge.

Here is the banjo installed without the gauge. Remember this is 18 ft-lbs max torque. Don't want this breaking under expansion and contraction.



And

I had the downpipe off, but there is plenty of room to do this from below after you remove the oil filter.

Here is the gauge line, remember this is a temporary setup for a shop gauge. I don't know how long this rubber hose would hold up over time.


Results: In a word awesome. Confirmed the motor is not bad.

I get about 16-18 psi at idle once fully warm


38 psi at 2000 RPM after a 50 min highway drive. I am just above factory spec (which is 36) but I am way ahead of the 10 psi per 1000 RPM general guide.

I should note that this is with 15-50 oil, it is all I had on the shelf and I bought it really cheap last year. It is fully syn Mobil oil though.

Last edited by Tboy; 05-19-2017 at 01:56 PM. Reason: Updated "after" pressure readings and added pics
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 10:24 AM   #11
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Next steps

I have confirmed my engine is not trash, but I am also not quite making the factory spec either.

Here is where I go from here:
1) I really want to get a good permanent gauge installed.
2) I'd like to replace the pump cover
3) might try the new gears again, but as it sits now I have the old gears in
4) would love an oil temp gauge. I have no idea what the oil temp is. It is hard to go by the factory spec without all the variables. I am only assuming now that the oil temp is correct. It may be too hot because my cooler is plugged, even with a low temp thermostat.
5) replace with Rotella T6 oil. This is my go to oil, I want to see what it generates with that oil.

If I had 30 psi @ 2000 RPM I think I will be happy. I will update as I find out more, but for now, the Aero is back on the road!
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 10:55 AM   #12
Elder
 
turbojohnny's Avatar
 
Join Date: Feb 2008
Location: Orchard Park, ny
Posts: 3,764
Congratulations Troy! Really great write-up. This should definitely be a sticky for reference of oil pressure problems.

I'm glad to hear the aero is still good to go.
turbojohnny is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-19-2017, 12:22 PM   #13
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Thanks,really hoping that the Honda measurements help people identify or eliminate concerns about their oil pumps. Keep in mind the measurements off mine are with 276k miles. I think the pumps are pretty robust except for when they are oil starved (like the pickup is sludged).

Last edited by Tboy; 05-19-2017 at 01:06 PM.
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-20-2017, 04:13 AM   #14
Drew In Houston
Elder
 
Join Date: Aug 2006
Posts: 2,638
Quote:
Originally Posted by Tboy View Post
Here is where I go from here:
1) I really want to get a good permanent gauge installed.
If you're comparing target numbers in WIS to real measurements, I think the back of the block where the stock sensor is located would give you the best basis for comparison, it's also probably the cleanest installation...that said, I think you're psyching yourself out a little over potential losses from a sandwich plate adapter. They're totally open inside, the central nipple ID is similar, and they're pretty short, maybe like 3/4" thick(?), I think it would be tough to measure the pressure drop across one.

Quote:
Originally Posted by Tboy View Post
2) I'd like to replace the pump cover
3) might try the new gears again, but as it sits now I have the old gears in
Maybe I missed it, but I didn't notice you mention checking the oil pressure bypass control. If you haven't, before doing anything more dramatic I'd take a look there. It's a spring loaded piston with what looks like some sort of low friction babbitt coating. They can get scratched/scored, or sticky/stuck. If you decided that you wanted to raise pressure as a test, you can try shimming that a little under the piston or even stretch the spring.

Quote:
Originally Posted by Tboy View Post

4) would love an oil temp gauge. I have no idea what the oil temp is. It is hard to go by the factory spec without all the variables. I am only assuming now that the oil temp is correct. It may be too hot because my cooler is plugged, even with a low temp thermostat.
5) replace with Rotella T6 oil. This is my go to oil, I want to see what it generates with that oil.
I'd look outside the WIS recommendations and look to oil manufacturer guidance for operating oil temperature ranges. There is definitely a relationship between viscosity and temperature, I think the OEMs hold info like that pretty close to the vest but you might be able to find some plots for various oils to consider and maybe even back out some estimated viscosity/measured pressure relationships on your setup, or go the other way and back out estimated viscosity per temp and pressure on your setup(?)

Quote:
Originally Posted by Tboy View Post
If I had 30 psi @ 2000 RPM I think I will be happy. I will update as I find out more, but for now, the Aero is back on the road!
Without knowing the temperature (and the the pressure bypass function) you might be chasing a moving target here--and the exact pressures don't really matter anyway, the primary function of the oil is to provide lubrication to keep wear low under all operational conditions. The other thing you could do, since it sounds like your engine isn't in acute danger, would be to keep running it the way it is and send off samples for wear analysis. If the reports comes back good then you know you have enough pressure because the oil is able to effectively perform it's primary function.
__________________
Co-Founder:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
First T7 19T turbo setup. First T7 Deka 80lb. injector setup.

Last edited by Trionic3000; 05-20-2017 at 04:49 AM.
Trionic3000 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-20-2017, 05:56 AM   #15
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Quote:
Originally Posted by Trionic3000 View Post
If you're comparing target numbers in WIS to real measurements, I think the back of the block where the stock sensor is located would give you the best basis for comparison, it's also probably the cleanest installation...that said, I think you're psyching yourself out a little over potential losses from a sandwich plate adapter. They're totally open inside, the central nipple ID is similar, and they're pretty short, maybe like 3/4" thick(?), I think it would be tough to measure the pressure drop across one.
Actually I think WIS shows a diagram of hooking up the pressure gauge to the spot I am showing, directly off of the turbo feed line. I don't think there is anything wrong with sandwich filter adapters, except where they measure does not measure restriction in the filter, and does not have the benefit of the oil being cooled. From my reading of WIS and looking at the diagrams filtration is the first thing that happens after the pump, then cooling and distribution. As you mentioned oil temp does have a lot to do with viscosity. So if you are going to use a sandwich adapter, I would plan to also capture temp so you capture enough info to make an informed decision.

Quote:
Originally Posted by Trionic3000 View Post

Maybe I missed it, but I didn't notice you mention checking the oil pressure bypass control. If you haven't, before doing anything more dramatic I'd take a look there. It's a spring loaded piston with what looks like some sort of low friction babbitt coating. They can get scratched/scored, or sticky/stuck. If you decided that you wanted to raise pressure as a test, you can try shimming that a little under the piston or even stretch the spring.
Yep, you missed that part. I actually dropped that first and checked for scoring. It didn't look to bad. I shimmed it two washers which I didn't think did anything, but that was before I put a good gauge on.


Quote:
Originally Posted by Trionic3000 View Post
I'd look outside the WIS recommendations and look to oil manufacturer guidance for operating oil temperature ranges. There is definitely a relationship between viscosity and temperature, I think the OEMs hold info like that pretty close to the vest but you might be able to find some plots for various oils to consider and maybe even back out some estimated viscosity/measured pressure relationships on your setup, or go the other way and back out estimated viscosity per temp and pressure on your setup(?)
With an oil temp reading this could be very helpful and I think good to do. WIS does specify what temp the oil pressure reading should be done. I think comparing that with some info you got from an oil manufacturer that would be really beneficial. It probably wouldn't be too hard to measure for an estimate. We used to use a zahn cup to measure paint viscosity. You could use that as a way to at least make comparisons.

Quote:
Originally Posted by Trionic3000 View Post
Without knowing the temperature (and the the pressure bypass function) you might be chasing a moving target here--and the exact pressures don't really matter anyway, the primary function of the oil is to provide lubrication to keep wear low under all operational conditions. The other thing you could do, since it sounds like your engine isn't in acute danger, would be to keep running it the way it is and send off samples for wear analysis. If the reports comes back good then you know you have enough pressure because the oil is able to effectively perform it's primary function.
I'm debating this currently. I wholeheartedly agree the only thing you need to know about oil pressure is if you have enough, or not. I was chasing an oil gauge that told me I had zero at idle, which is of course alarming. But whether you have 36 or 38 psi at a certain rpm is maddening, and perhaps only causes you frustration.

Used oil analysis is an excellent idea, I had not thought about that. Definitely worth spending some money on.

Good discussion thanks for adding Drew!
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-29-2017, 09:20 AM   #16
Elder
 
turbojohnny's Avatar
 
Join Date: Feb 2008
Location: Orchard Park, ny
Posts: 3,764
Quote:
Originally Posted by Tboy View Post

Here is the banjo installed without the gauge. Remember this is 18 ft-lbs max torque. Don't want this breaking under expansion and contraction.

Troy, where did you get this banjo adapter? What is the thread on the banjo side? I would like to find one of these for our '03 vert.
turbojohnny is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-29-2017, 09:55 AM   #17
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
I got it from Glowshift. It is listed for a Cummins fuel rail.

Fuel Pressure Banjo Bolt for 1994-1997 Dodge Ram 12 Valve Cummins

It is m14x1.5 on the banjo end, and has female 1-8 npt in the other end. Comes with crush washers that are different than the Saab ones, but they worked none the less.

No issues so far.

Troy
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 06-09-2017, 09:21 AM   #18
Elder
 
turbojohnny's Avatar
 
Join Date: Feb 2008
Location: Orchard Park, ny
Posts: 3,764
Quote:
Originally Posted by Tboy View Post

Results: In a word awesome. Confirmed the motor is not bad.

I get about 16-18 psi at idle once fully warm
In the '03 after about an hour of driving we're at about the same. 17-18 PSI at idle.
turbojohnny is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 06-09-2017, 09:58 AM   #19
Live, eat, and sleep by TSL
 
Join Date: Mar 2005
Posts: 1,819
Quote:
Originally Posted by turbojohnny View Post
In the '03 after about an hour of driving we're at about the same. 17-18 PSI at idle.
That's great news!

I still have my shop gauge installed. Trying to decide what to do. I don't want to look at it constantly like I would a boost gauge, but would like to check in on it from time to time.
Tboy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 06-09-2017, 10:03 AM   #20
Elder
 
turbojohnny's Avatar
 
Join Date: Feb 2008
Location: Orchard Park, ny
Posts: 3,764
OLED digital single oil pressure gauge
That's about $89 USD, I think he charged me $35 for shipping.
I'm sure you can find a way to install it hidden in your glovebox.

Last edited by turbojohnny; 06-09-2017 at 10:07 AM.
turbojohnny is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the The Saab Link Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Vehicle Info.
Enter your vehicle information (year, model, mods)
Insurance
Please select your insurance company (Optional)

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -8. The time now is 02:31 AM.


Powered by vBulletin® Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Friendly URLs by vBSEO 3.5.2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
All content is copyright The Saab Link and it's original authors.


 

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.