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This is the remote locking clamp pliers that got clamp off bottom of AOS, which is tied with removing stripped AOS socket head bolt as hardest part of job so far.
Pliers have two major design flaws; locking wheel should be multiple times larger with many more teeth because clamping steps are way too large to get required opening diameter and pliers have to be squeezed hard at end of travel to get clamp to actually release hose, and slide is so wide it is very hard to position jaws on clamp. A dremel could remove some of the slide that is not needed, and I will do if using this tool on a regular basis. The installed jaws are for medium clamps and the clamp on the AOS is out of range on the small side which requires manually squeezing handles, the two other jaws below it are easily installed, one for medium and large clamps and the other for crimping? There were no instructions in tool packaging.
Other work done yesterday: I could not remove two of the larger hoses to the installed AOS so had cut them off, and this resulted in many black plastic chips in the hose under the AOS which I think feeds oil into the crankcase, using a wetvac it pulled all the chips out. A cut off port from the AOS was still stuck in the lower hose and when maneuvering hose to remove cut off piece, the corrugated hose made a crackling sound, so before reassembly will find a way to apply smoke to hose to ensure there are no actual cracks. Small hose from top of power steering reservoir was occasionally dripping so checked reservoir level and it was way over full, using turkey baster removed fluid and don't understand how it got over full?
For those of you who have the UAOS installed I’m curious what your manometer readings were before the install and after the install.
The UAOS runs about 1 inh2o lower than the Factory AOS. Usually about 3.5 -4.5 inh2o. Any lower and I start to suspect the crankcase is not sealed well, a cracked oil fill tube ect.
The UAOS systems "flow control" has 4 pressures at work with/against each other.
Engine vacuum negative pressure(variable) and Atmospheric pressure(static) "against" spring pressure (static) and crankcase pressure (variable), to keep a constant slight negative pressure (- 3.5 - -4.5 inh2o) throughout the entire load range..
I guess I should also point out that in Laymen terms to understand the dynamics of the flow control, the Atmospheric pressure should be considered static, because the changes are slight compared to engine vacuum, where Atmospheric pressure changes slightly with weather and more due to Altitude ( 1-2 inHG), Scientifically it would be considered a variable, but not a variable compared to engine vacuum that will change from 0-29 inHG with engine load....Note;; 1 inHG equals 13.6 inH2o
The UAOS runs about 1 inh2o lower than the Factory AOS. Usually about 3.5 -4.5 inh2o. Any lower and I start to suspect the crankcase is not sealed well, a cracked oil fill tube ect.
I have so many of the UAOS's in CA and the Aluminum Version is so popular, I'm designing a "snap on" plain Nylon cover to be more incognito and quick to take on and off... According to the CARB Appendix G there should be no problem with the UAOS, but I wonder how many Inspectors have actually read the Apendix G...
My vacuum reading is 5.2 as a high and 4.8 lowest of 4 different days with UAOS.
Mt Juliet Tn has an elevation of 600ft, that's an 8.5 inH2o difference from Seal Level for Atmospheric pressure, and Atmospheric pressure is only 1 of 4 balancing pressures of the UAOS..Yours is fine..
Originally Posted by De Jeeper
Mine was 22 and now 4.5. Obviously the aos had failed.
Yep, clearly failed. The Dual Oil Separators and warning system of the UAOS stops the threat of Hydrolock. People who ignore this threat and just lump it into the IMSB, Bore Score,cracked head list of "it won't happen to me" and gamble, need to know, the Hydrolock failures are "Secondary Catastrophic Failures" of a simple little split in a rubber diaphragm ..lol .. Being a Dealer Tech and Racer for 45 years, hardly anything surprises me, I had seen many many AOS fail and replaced quite a few M96 due to Hydrolock, and thought how can owners let this happen to their car, weren't they paying attention?,but was totally surprised by how FAST this can turn SERIOUS when you witness it first hand, and are only safe if you drive like a Grandma most of the time until you have the UAOS.
With that reading, what symptoms did you experience? Or did you just do a manometer test, saw the reading and replaced?
Originally Posted by De Jeeper
No symptoms at all. i even tracked a day because ignorance is bliss.
Found it with a nanometer test because i wanted to do some track days and skip had just released the unit so i figured i would check it jic.
Found some email paperwork from the po and it was replaced with a factory porsche in 2015, about 15k miles ago.
Any Manometer reading above -7 inH2o is a faulty flow control. And even a Brand New Porsche AOS is not safe. Last year an FSI and an RND engine failed by Hydrolock due to Brand New Porsche AOS's.. Jake mentioned he had Inspected these Post-Mortem to find the root cause. FSI is offering the UAOS for all M96 engine builds.
The UAOS with Primary and Secondary oil separator/accumulator and warning system is the only safe solution.
A tear in the diaphragm of only .060 in (the size of the Atmosphere port) can cause the crankcase pressure to swing wildly up to -400 inh20 (29 inHG) !!!! It is much worse on high RPM deceleration like you see after long straights on the Track. If the tear in the diaphragm is less than .060 in you can see slightly higher Manometer readings in H2o at idle, but will swing in large amounts and delay in response while driving. I have seen the readings go from -50inH20 at startup instantaneously, then and slowly go down to 5-7 inh2o after 20-30 seconds. When the flow control is working properly, it will maintain a consistent slight -inH2o under all circumstances from instantaneous startup to high RPM deceleration and everything in between..
Last edited by Porschetech3; 02-15-2021 at 06:35 PM.
Got ours finished today. Upon starting a neighbor came over thought my garage was on fire. Drove about 20 miles finally burned off all the oil in mufflers, and engine running normally with no CEL. If doing again would drop engine or take to professional. Thanks for tips you guys provided, if you hadn't teased me with the brass and aluminum bolts comments, I would not have been aware would have stripped bolts with the ball end allen tool I fabricated. Instead only used that tool to start socket head bolts holding down AOS and farthest manifold position, then make a second tool out of a long arm allen wrench to torque AOS and farthest manifold socket head bolts to 7.5 ft/lbs.
$10 pump from Home Depot and $5 cigar, did smoke checks to installed AOS then manifold and plenums. It seemed to pump smoke and none came out of any parts of the engine.
02-03-2021, 09:35 AM
