Measured my crankcase vacuum...@ ~6" water
#1
Nordschleife Master
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I read it in Excellence mag or somewhere that the crankcase pressure should not exceed 9" H2O, otherwise the AOS may be faulty and creating too much vacuum. Mine measured ~6" H2O.
I used a clear tube partially filled with engine oil instead of water in case it gets sucked into the engine. Then I adjusted for specific density. Now that I have a baseline for future reference![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
***Update: Normal value should be 4-6" water. See the article here
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I used a clear tube partially filled with engine oil instead of water in case it gets sucked into the engine. Then I adjusted for specific density. Now that I have a baseline for future reference
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
***Update: Normal value should be 4-6" water. See the article here
![Name: Drawing1 (Small).jpg
Views: 1913
Size: 21.4 KB](https://rennlist.com/forums/attachments/996-forum/698791d1359357071-measured-my-crankcase-vacuum-6-water-drawing1-small-.jpg)
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Last edited by Ahsai; 01-28-2013 at 03:30 PM. Reason: Added link to the relevant article
#2
Instructor
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Oil has lower density than water, hence it makes sense that the column will be higher. You can search online for density difference - the height column will be proportional. I bet it's 0.8x lighter, hence 6" oil equals roughly 5" water...
#3
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I measured ~7" oil pressure.
#4
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I had Tony Callas of Callas Rennsport, who may have written the article you read, measure mine with a manometer he uses on BMWs. My rebuilt engine had 5 inches at idle, which Tony said is ideal.
#5
Nordschleife Master
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That's it! I knew I read it somewhere...just escaped my mine who wrote that article. Thanks for the 5-inch data so now I know I'm not too far from it at ~6" H2O.
#6
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Tony writes a column for Panarama & Excellence.
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#8
Instructor
#9
Nordschleife Master
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good info, thanks for sharing. This method was what I had in mind for later:LINKY>>>> http://www.renntech.org/forums/tutor...for-a-bad-aos/
http://www.youtube.com/watch?v=axBNu...layer_embedded
http://www.youtube.com/watch?v=axBNu...layer_embedded
I figured. It's good to explain to other people anyway
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
#11
Burning Brakes
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I've only got 4 inches and I'm NOT happy about it!