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05 996 C4s MT - 75k miles - NOT removing the heads - no maintenance records.
Wish Porsche would download maintenance records according to VIN. Tried when I purchased the car four years ago.
Thoughts on replacing the associated AOS hoses/vacuum lines (4, 10, 12, 13, 20)? 996 PET AOS.pdf
Just ordered the URO aluminum cooling hose connector.
What have other folks seen on the condition of these hoses?
Not looking to replace parts just to replace, car is in great condition but it is 15 years old and has 75K on the clock.
Dropping the engine and trans to do the IMS, RMS, clutch/PP/bearing/flywheel,/bolts updated clutch fork and UAOS.
While in there want to replace the plugs, coils, injectors, oil pressure relief valve/spring O-ring, chain adjusters, chain guides/paddle, cam lugs, oil pressure switch, heat exchanger,
upstream O2 sensors, water pump/bolts/thermostat/hoses with plastic ends/T's, pully belt tensioners, associated hoses, O-rings, gaskets.
Parts count and $ is not insignificant.
Great car I plan to have for awhile.
Appreciate the forums thoughts and advice!
Cheers, Glenn
#4 would be a good "while you are in there" item, You already have a new #10 that came with the UAOS kit.
12 13 18 and 20 should be re-freshed with new if original, but can also blocked off when using the UAOS System.
I think I'll start including 2 Nitrile block off caps and spring clamps with each 996 UAOS kit.That will eliminate a few more failure points ( although non-catastrophic), and will add very little to install effort.
Getting rid of 18 would be great.
Any tips for cutting the Oettinger clamp on the lower end of 20?
I have a large set of nipper I use for the upper clamp.
But there’s no way they’re fitting down there to get the other end.
Getting rid of 18 would be great.
Any tips for cutting the Oettinger clamp on the lower end of 20?
I have a large set of nipper I use for the upper clamp.
But there’s no way they’re fitting down there to get the other end.
I agree, #18 has been a "gotcha" moment for many, I have never seen it be root cause of catastrophic failure (Unlike AOS/IMS), due to the low coolant sensor catching small leaks, and the big "gushers" happen while working on the car...lol
Small precision screw driver (like watch/jewery repair) can be inserted into the "pinch point" to spread the Oetiker clamp to get it off without cutting it.
Last edited by Porschetech3; 03-13-2021 at 10:14 PM.
Skip,
Fantastic info, elimination the coolant side lines and feed thru.
Replace hose 4, hoses 5 and 10 are provided in the UAOS.
Line 12 can be cut and blocked off at 15/16.
Line 20 cut an blocked off at lower clamp 19.
Lines 9 and 13 eliminated.
Hoses retained 4, 5 (supplied), and 10 (supplied).
Anything need to be done with the open coolant AOS vent tubes 12 and 13 were plugged into?
I will slide rubber caps over the open vent tubes and clamp.
Skip,
Fantastic info, elimination the coolant side lines and feed thru.
Replace hose 4, hoses 5 and 10 are provided in the UAOS.
Line 12 can be cut and blocked off at 15/16.
Line 20 cut an blocked off at lower clamp 19.
Lines 9 and 13 eliminated.
Hoses retained 4, 5 (supplied), and 10 (supplied).
Anything need to be done with the open coolant AOS vent tubes 12 and 13 were plugged into?
I will slide rubber caps over the open vent tubes and clamp.
Does this sound correct?
Cheers,
Glenn
You got the right idea, but instead of cutting and plugging 12 an 20, just remove them and install Nitrile or NBR rubber caps and clamps on the nipples. I will source the proper sizes/types today and let you know. I will start including them the in the UAOS kits.( and revise the Install instructions)
Yes just cap the tube nipples on the AOS housing, clamps wont be necessary and plain rubber vacuum caps will be OK.( would actually be ok to leave open but wouldn't look completed or Professional)
Correct, a new #4 if yours is original, #5 and #10 come with the UAOS kit.
Last edited by Porschetech3; 03-14-2021 at 11:09 AM.
What is the downside of capping the coolant flow through the AOS?
Why was is it there in the first place?
I just got mine back together after a UAOS install, so won't do this now, but I'm always intrigued by simplifying things.
What is the downside of capping the coolant flow through the AOS?
Why was is it there in the first place?
I just got mine back together after a UAOS install, so won't do this now, but I'm always intrigued by simplifying things.
The coolant flow through the AOS was to act as a heater to keep from freezing water vapor in very cold temp at the high velocity pressure drop. In the UAOS System, that high velocity pressure drop is eliminated in that area, so no chance creating ice in that area.
The coolant flow through the AOS was to act as a heater to keep from freezing water vapor in very cold temp at the high velocity pressure drop. In the UAOS System, that high velocity pressure drop is eliminated in that area, so no chance creating ice in that area.
Thanks. Makes sense.
Now I wish I had been even slower getting everything back together, I would have done this. But I suppose having the car apart 4 months is long enough and I need to get it started and tested.
Install question: (I could start a new thread, but this is 50% related to the UAOS install.) Appologies if it's in this thread already, I didn't find it, but let me know.
Since I had both manifolds off, replaced the fuel injectors, replaced the vacuum lines, and of course the UAOS, what should I monitor on the first restart?
I'm thinking:
1) Visible leaks (coolant / fuel)
2) strange sounds
3) all fuel trims (I have pre-install numbers) in durametric
4) after warmed up, manometer check of AOS pressure, then crankcase pressure (because why not; I also have pre-install numbers).
5) ?
Thanks!
Thanks. Makes sense.
Now I wish I had been even slower getting everything back together, I would have done this. But I suppose having the car apart 4 months is long enough and I need to get it started and tested.
Install question: (I could start a new thread, but this is 50% related to the UAOS install.) Appologies if it's in this thread already, I didn't find it, but let me know.
Since I had both manifolds off, replaced the fuel injectors, replaced the vacuum lines, and of course the UAOS, what should I monitor on the first restart?
I'm thinking:
1) Visible leaks (coolant / fuel)
2) strange sounds
3) all fuel trims (I have pre-install numbers) in durametric
4) after warmed up, manometer check of AOS pressure, then crankcase pressure (because why not; I also have pre-install numbers).
5) ?
Thanks!
Originally Posted by jdbornem
Second question.
Does everyone elses air intake sit right against the UAOS catch tank?
It will rub over time. Is this a problem?
Yes, check for leaks,noises, if all ok then check fuel trims.
Checking crankcase vacuum with UAOS, and also blow-by will be easy for you since you have already done that..
The snorkel fit is very floppy on most cars and can have adequate clearance or not. The air cleaner is a three point mount and the snorkel can be very effected by the left rubber mount. a small adjustment to the rubber thickness mount will make a big difference in snorkel to Accumulator clearance..If the left rubber mount is missing or flattened out from time of use the snorkel will be touching the Accumulator.
I have noticed many Rennlisters have a lot of trouble finding vacuum leaks on the M96 engines, even with a smoke tester. I think I will develop a method of testing engine for leaks using Freon and a Freon leak detector. Even the low end Freon leak testers will detect leaks as small as .4 grams per year, and the audible alerts and long bendable sensor probe can get to all places on the engine..
Normal is good. I see a lot of the white milky stuff in the fill caps of air cooled generators I work on because of moisture and limited use so I try to correlate what I see to this.
Normal is good. I see a lot of the white milky stuff in the fill caps of air cooled generators I work on because of moisture and limited use so I try to correlate what I see to this.
yea, its unusual to see an oil cap off an M96 that is perfectly clean...unless its just been cleaned or new...lol
03-13-2021, 02:54 PM
