Crankcase Breathers |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Crankcase Breathers |
McMark |
Sep 12 2017, 04:58 PM
Post
#41
|
914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
I was looking at the factory manuals and talking with someone about crankcase breathers. We were talking about breather setups for carbs specifically. And I realized as I was looking at the breather diagram that it appears that the breather ports on the heads were included to supply extra air to flow through the engine case. And then I read this little snipped in the manuals which seems to support my thought:
QUOTE Crankcase ventilation has been considerably improved in the engine by ducting fresh air from the air filter. This modification reduces crankcase condensation and icing at low outside temperatures. So following that logic... If the crankcase breather (at the oil filler neck) isn't connected to a vacuum source, then the ports at the heads should/could be plugged instead of connected to a breather box. Thoughts? Contradictions? Agreement? I realize people have been connecting breathers all sorts of different ways and most work just fine. I'm more interested in the theory aspect, and refining an 'ideal' installation since we already know many ways to 'make it work'. Attached image(s) |
Spoke |
Jan 5 2018, 07:23 PM
Post
#42
|
Jerry Group: Members Posts: 6,992 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
|
gothspeed |
Jan 5 2018, 07:34 PM
Post
#43
|
Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
Tangerine system with crankcase vented back to the intakes on both sides. After running this for a while, I checked in the air cleaners and no oil residue found. Great system; well engineered and fabricated. Cool, another tangerine tank (IMG:style_emoticons/default/smile.gif) ..... does your engine have or use cylinder head vents? |
Spoke |
Jan 5 2018, 08:31 PM
Post
#44
|
Jerry Group: Members Posts: 6,992 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
Tangerine system with crankcase vented back to the intakes on both sides. After running this for a while, I checked in the air cleaners and no oil residue found. Great system; well engineered and fabricated. Cool, another tangerine tank (IMG:style_emoticons/default/smile.gif) ..... does your engine have or use cylinder head vents? I routed a hose between the 2 head vents. I read about it somewhere here. Don't recall who suggested it. |
gothspeed |
Jan 6 2018, 12:13 AM
Post
#45
|
Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
Tangerine system with crankcase vented back to the intakes on both sides. After running this for a while, I checked in the air cleaners and no oil residue found. Great system; well engineered and fabricated. Cool, another tangerine tank (IMG:style_emoticons/default/smile.gif) ..... does your engine have or use cylinder head vents? I routed a hose between the 2 head vents. I read about it somewhere here. Don't recall who suggested it. Interesting, i have read that a few times on here. im thinking i will go that route on the heads and use a pcv for the crank case vent. i might even measure the pressure if any on the cylinder heads. Just to see what is going on in there. (IMG:style_emoticons/default/smile.gif) |
98101 |
Jan 6 2018, 01:46 AM
Post
#46
|
Michael in Seattle Group: Members Posts: 373 Joined: 7-October 17 From: Seattle, WA Member No.: 21,495 Region Association: Pacific Northwest |
Interesting, i have read that a few times on here. im thinking i will go that route on the heads and use a pcv for the crank case vent. i might even measure the pressure if any on the cylinder heads. Just to see what is going on in there. (IMG:style_emoticons/default/smile.gif) I'm very interested to hear what you find. Empirical facts trump guesswork every time. |
gothspeed |
Jan 6 2018, 10:03 AM
Post
#47
|
Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
Interesting, i have read that a few times on here. im thinking i will go that route on the heads and use a pcv for the crank case vent. i might even measure the pressure if any on the cylinder heads. Just to see what is going on in there. (IMG:style_emoticons/default/smile.gif) I'm very interested to hear what you find. Empirical facts trump guesswork every time. Yes, i primarily want to learn more on why some engines nearly fill their valve cover chambers with oil at higher rpm. was it because the crankcase had high pressure or because valve chamber had a huge vent along with high crankcase pressure? However so far most info i have read about seems to support having lower crankcase pressure. Here is one example: http://dsportmag.com/the-tech/quick-tech-t...ressure-part-1/ |
Lo-Fi Version | Time is now: 9th June 2024 - 08:30 PM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |