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Does anybody have any hints on routing the 15mm vacuum line and elbow that serves the brake booster, circled in red below? Seems like the only place for it to go is as shown, but the hard plastic corrugated line is very tight when connected. I was smoke testing the engine tonight chasing a vacuum leak and found that this elbow was leaking significantly. The o-rings inside are shot and I have a new one on order, but it seems like this is under a bit of stress installed like this.
From the side, you can see that the hose between the diaphragm and the square UAOS collector is right in the way of where the elbow and hard line originally ran. That means I really have to push the elbow and line hard into the rubber hose connecting the diaphragm and the square UAOS collector to get the pieces together, deforming the large rubber hose:
Another view:
It works ok and I think I'll get rid of the vacuum leak with the new elbow, but things seem too tight to me, especially since there can be relative motion/movement between the engine and the hard plastic corrugated line as the engine is under load and rotates slightly.
Any ideas welcome and appreciated, even if it's just "it works fine for me"- that's also helpful.
Thanks, and thanks Skip for all of the great assistance in making things better! By the way the 1-3 EXH camshaft you sent me worked perfectly and the car is running great.
Glad you got the cam in and the engine is now working well !!
Looks like you have an early 99 C2, pick up a Dorman 46051 and two 18mm spring clamps for a local auto parts store., it's a 15mm ID rubber elbow to replace the plastic elbow with the internal o-rings that leak. The rubber elbow fit a LOT better.
I have been including the Dorman 46051 in ALL 99c2 kits (whether early or late) for over 6 months, so you have had that kit for a while..
Glad you got the cam in and the engine is now working well !!
Looks like you have an early 99 C2, pick up a Dorman 46051 and two 18mm spring clamps for a local auto parts store., it's a 15mm ID rubber elbow to replace the plastic elbow with the internal o-rings that leak. The rubber elbow fit a LOT better.
I have been including the Dorman 46051 in ALL 99c2 kits (whether early or late) for over 6 months, so you have had that kit for a while..
Does this also work for 996.2? I also had issues getting a seal on this connection.
Does this also work for 996.2? I also had issues getting a seal on this connection.
Hi Joe,
Here is a pic of the late 99C2 and up intake adaptor
Late 99c2 and up intake adaptor
This is a pic of the early 99C2 intake adaptor ..
Early 99C2 intake adaptor
You can use the Dorman 46051 15mm rubber elbow and two 18mm spring clamps to eliminate the internal o-ringed connectors , IF you get the early 99C2 adaptor part# 99611015151
Glad you got the cam in and the engine is now working well !!
Looks like you have an early 99 C2, pick up a Dorman 46051 and two 18mm spring clamps for a local auto parts store., it's a 15mm ID rubber elbow to replace the plastic elbow with the internal o-rings that leak. The rubber elbow fit a LOT better.
I have been including the Dorman 46051 in ALL 99c2 kits (whether early or late) for over 6 months, so you have had that kit for a while..
Skip,
The Dorman 46051 120 degree elbow worked great...WAY better fit and actually seals (unlike the factory one). Passed the smoke test 1st time.
Put 500 miles on the car this weekend...running really well.
Thanks man!
Kris Murphy and Pete Thank you guys!
Dr. Thank you again
All sorted and finally done as the oil filler came in. My exhaust had a leak so I swapped that out too. I had a hard time routing the tube around alternator but all done. Takes time and patience.
Kris Murphy and Pete Thank you guys!
Dr. Thank you again
All sorted and finally done as the oil filler came in. My exhaust had a leak so I swapped that out too. I had a hard time routing the tube around alternator but all done. Takes time and patience.
Kris Murphy and Pete Thank you guys!
Dr. Thank you again
All sorted and finally done as the oil filler came in. My exhaust had a leak so I swapped that out too. I had a hard time routing the tube around alternator but all done. Takes time and patience.
I perused some of your posts and could not find therein a response to the post by Stalan, and especially a question from Jake Raby, a few years back regarding his modified AOS and (if I understood correctly) the fuel ratio response that was discussed in the Boxster thread http://986forum.com/forums/boxster-g...arket-aos.html. Can you comment how your system prevents the issues raised by Jake in that thread and how it addresses changes in engine displacement?
I perused some of your posts and could not find therein a response to the post by Stalan, and especially a question from Jake Raby, a few years back regarding his modified AOS and (if I understood correctly) the fuel ratio response that was discussed in the Boxster thread http://986forum.com/forums/boxster-g...arket-aos.html. Can you comment how your system prevents the issues raised by Jake in that thread and how it addresses changes in engine displacement?
A rather simple explanation would go like this::
The Crankcase Ventilation Systems on the M96/7 engine are unique. They are sealed systems that uses a flow regulator that balances 4 forces for flow regulation ( Intake Vacuum pressure, Crankcase pressure, Spring pressure, and Atmosperic pressure). By doing it this way, it is a much more effective as it can adjust for blow-by volume changes from load changes from idle to full throttle, and more importantly for changes due to mileage/wear.
The DME/ECU is calibrated for the extra water vapor/Oxygen that is in the blow-by gasses..Blow-by gasses have 13% water vapor, (water vapor is 88% Nitrogen 21% Oxygen).
The Air-Oil Separation (AOS) is a necessary part of the Crankcase Ventilation System in the M96/7 engines to get the oil droplets out of the blow-by gases before they are reintroduced into the engine.
Other attempts at "AOS systems" failed because they didn't fully understand the way the Crankcase Ventilation System on the M96/7 works, so in an attempt to correct "AOS problems" they created Crankcase Ventilation System issues.. Things like increased volumes of internal air displacement (eg large catch cans) and would not be calibrated to the fuel trims of the DME(rich running), or would use a different method of blow-by flow regulation (that is not compatible with Porsche DME/ECU) or would also vent to Atmosphere (Illegal) , or use a "PCV" valve with" fresh air" that is also not compatable with Porsche DME/ECU ..Most all these would be Illegal in the 48 states, the UAOS is Legal.
Porsche even attempted to correct an "AOS problem" in mid 2002 on m96 engines by lowering the oil level by 1/2 qt. via a new dipstick and revised dash calibration. With the UAOS and hm/XTDD we are finding this to no longer be necessary and are reversing this recommendation.<<< THIS IS A BIG DEAL !!!
Yes the UAOS was evaluated/tested by FSI for about a year and fully tested on an R40 engine, and is also available as an Option on the FSI Engine Program.
Last edited by Porschetech3; 08-29-2021 at 01:49 AM.
Cant speak to the displacement but it would appear that the UAOS has passed FSI testing, here's Pauls engine he just got back today :
Yes, this UAOS was installed by FSI during my engine reconstruction. I'm not sure it's the first one they did after their testing, but it is close. It was not yet on their standard list of optional upgrades. Before the car left for FSI, I had decided I would change over to the UAOS. The only thing to figure out was timing. Lucky for me they had already tested it. I believe it's also on the LN Engineering website for sale. A really nice and very useful piece of tech.
08-19-2021, 02:01 AM
Hints on the brake assist vacuum line?
