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--- techtalk:ref:engmech05 [2020/03/02 00:11]
hippysmack [Pics of Aftermarket Breather Valves]
+++ techtalk:ref:engmech05 [2020/03/02 01:44]
hippysmack [Aftermarket Breather Valves]
@@ Line 164: / Line 164: @@
 ====== Aftermarket Breather Valves ======
-|Doherty Power Vents with the line routed up then \\ down and attached to the bottom of the frame. ((photo by RIORoosen of the XLFORUM http://xlforum.net/forums/showthread.php?t=146084&page=18))|
+==== Sub Documents ====
-|{{:techtalk:ref:engmech:breather_mod_by_rioroosen.jpg?direct&300|}}|
+  * [[techtalk:ref:engmech04a|Dissecting the Hayden KVP38 Crankcase Breather Valve]]
+  * [[techtalk:ref:engmech04b|Frequently Asked Questions About the Hayden Krankvent]]
+There is a product called a Krankvent that can be plumbed into the lower, 6 o’clock position as an alternative to a stock foo-foo valve. ((Hopper of the XLFORUM http://xlforum.net/forums/showthread.php?t=518948&highlight=cam+chest+breather)) \\
+But they are not cheap. Automotive PCV valves are not really made to handle the revs or air volumes of a Harley. \\
+While a car engine is bigger, it has one piston coming down while one goes up. \\
+So there's not much change in internal crankcase volume, so not as much breathing to be done. \\
+A Harley has two pistons and rods on one crankpin, so is one giant air compressor. \\
+Some guys have found that plumbing in a 77-78 foo-foo valve on the later model engines improves breathing. \\
+**Finding a better breather valve**: ((bunny32 of the XLFORUM http://xlforum.net/forums/showthread.php?t=15705&page=2)) \\
+The breather valves that work best on crankcase breathers have several features: \\
+  * Low-inertia, i.e. they don't take more than a breath to open and close.
+  * They operate at low pressures ~1-30psi.
+  * They preferably have a floating type seal.
+  * They should be transparent, so you can see if they block up with blowby, solids, bugs etc.
+  * They should be easy to open and clean occasionally.
+  * They should push-fit into your breather line.
+Metal diaphragm valves with e.g. springs are hopeless. \\
+Also avoid other types of valves designed to work at high pressures e.g. plumbing valves. \\
+Avoid car PCV valves as they are metering as well as non-return valves and are unsuitable. \\
+Automotive PCV valves are designed to let some air back in. \\
+The ball and spring valves will not be able to work fast enough to keep all the air out. \\
+When air is allowed to be drawn back into the engine, it creates a mass that must be compressed by the pistons on downstroke as it is being vented out. \\
+This robs some power and will cause the engine to work harder (creating more internal heat at higher RPM). ((Deimus of the XLFORUM http://xlforum.net/forums/showthread.php?t=67658&page=18)) \\
+Aftermarket PCV's: ((electronbee of the XLFORUM http://xlforum.net/forums/showthread.php?t=72099&highlight=reed+valve&page=10)) \\
+  * Mercedes Benz P/N# 271-018-00-29 ~$13.
+    * Reed type PCV valve. Fast acting. Used for their C 230 Kompressor engine.
+    * Dims: 2-1/2" long by 1-1/8" with an I.D of 1/4".
+  * McCaster Carr P/N# 4610K17 ~$6.
+    * Umbrella valve. Vacuum check valve.
+  * Autozone P/N# PCV1174 (PV272) ~$5.
+  * Ball/spring based PCV valve.
+    * Makes a clicking noise during operation.
 |Hayden KVP38 breather valve, used with the \\ [[techtalk:ref:engmech05d|Deimus Mod]] (cam chest breather conversion). ((photo by 60Gunner of the XLFORUM http://xlforum.net/forums/showthread.php?p=5763918#post5763918))|  Hayden breather opened up. ((photos by leucadiaGuit of the XLFORUM http://xlforum.net/forums/showthread.php?t=2004869 cropped by Hippysmack))  ||
 |{{:techtalk:ref:engmech:deimus_mod_8_by_60gunner.jpg?direct&300|}}|{{:techtalk:ref:engmech:hayden_krankvent_3_by_leucadiaguit_-_cropped.jpg?direct&300|}}|{{:techtalk:ref:engmech:hayden_krankvent_2_by_leucadiaguit_-_cropped.jpg?direct&300|}}|
+|  Here is a 2-stroke reed valve. ((photo by norseXL of the XLFORUM http://xlforum.net/forums/showthread.php?t=1386341&highlight=reed))  |  Reed Valve ((photo by Bluto of the XLFORUM http://xlforum.net/forums/showthread.php?p=5761290#post5761290))  |
+|{{:techtalk:ref:engmech:reed_valve_by_norsexl.jpg?direct&300|}}|{{:techtalk:ref:engmech:reed_valve_by_bluto.jpg?direct&300|}}|
+|  Mercedes Benz P/N# 271-018-00-29 ((photo by electronbee of the XLFORUM http://xlforum.net/forums/showthread.php?t=72099&highlight=reed+valve&page=10))  |
+|{{:techtalk:ref:engmech:mercedes_benz_pcv_valve_by_electronbee.jpg?direct&300|}}|
+|Doherty Power Vents with the line routed up then \\ down and attached to the bottom of the frame. ((photo by RIORoosen of the XLFORUM http://xlforum.net/forums/showthread.php?t=146084&page=18))|  Doherty Power Vent ((Photo by goblin_dust of the XLFORUM http://xlforum.net/forums/showthread.php?t=72099&highlight=wet+sumping&page=23))  |
+|{{:techtalk:ref:engmech:breather_mod_by_rioroosen.jpg?direct&300|}}|{{:techtalk:ref:engmech:deimus_mod_2_by_goblin_dust.jpg?direct&300|}}|

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