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techtalk:evo:engmech07 [2022/05/12 18:26] hippysmack [Late 1984-1990 Sportster Breather Valve] |
techtalk:evo:engmech07 [2023/12/26 20:23] (current) hippysmack |
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| 86-90 engines vent through a valve in the cam cover. \\ | 86-90 engines vent through a valve in the cam cover. \\ | ||
| 91 and up engines vent through a valve in each rocker box and out the hollow breather bolts in each head to the air cleaner. \\ | 91 and up engines vent through a valve in each rocker box and out the hollow breather bolts in each head to the air cleaner. \\ | ||
| - | |||
| ====== Late 1984-1990 Sportster Breather Valve ====== | ====== Late 1984-1990 Sportster Breather Valve ====== | ||
| - | |||
| **An important note**: \\ | **An important note**: \\ | ||
| Factory engine breather valves on all Evo Sportsters are inside the engine. \\ | Factory engine breather valves on all Evo Sportsters are inside the engine. \\ | ||
| Line 28: | Line 26: | ||
| * 1986-1990 engines continued the breather baffle tube system (implemented in L1984) incorporated into the cam cover in the area behind the oil filter. | * 1986-1990 engines continued the breather baffle tube system (implemented in L1984) incorporated into the cam cover in the area behind the oil filter. | ||
| - | * The baffle tube mounts into the cam cover and the rubber umbrella installs into the center of the baffle tube. ((Gary E of the XLFORUM http://xlforum.net/forums/showthread.php?t=2071387&page=8)) | + | * The baffle tube mounts into the cam cover and the rubber umbrella installs into the center of the baffle tube. ((Gary E of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/195092-rigid-evo-oil-check-ball-spring/page8?t=2071387&page=8)) |
| * On each piston downstroke, crankcase pressure (air and oil mist) is routed to the breather baffle at the front of the cam case. | * On each piston downstroke, crankcase pressure (air and oil mist) is routed to the breather baffle at the front of the cam case. | ||
| * Oil is separated from the air pressure by the one-way umbrella valve. | * Oil is separated from the air pressure by the one-way umbrella valve. | ||
| Line 35: | Line 33: | ||
| * The air is then routed into the rear of the air cleaner via an oil hose to the cam cover. | * The air is then routed into the rear of the air cleaner via an oil hose to the cam cover. | ||
| - | **Umbrella check valve comparison**: ((Gary E of the XLFORUM http://xlforum.net/forums/showthread.php?t=2071387&page=8)) \\ | + | **Umbrella check valve comparison**: ((Gary E of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/195092-rigid-evo-oil-check-ball-spring/page8?t=2071387&page=8)) \\ |
| Outside diameter: \\ | Outside diameter: \\ | ||
| 26856-82 - 1.25" \\ | 26856-82 - 1.25" \\ | ||
| 26856-89 - 1.0" \\ | 26856-89 - 1.0" \\ | ||
| - | Edge thickness (1/8" in average): ((Gary E of the XLFORUM http://xlforum.net/forums/showthread.php?t=2071387&page=8)) \\ | + | Edge thickness (1/8" in average): ((Gary E of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/195092-rigid-evo-oil-check-ball-spring/page8?t=2071387&page=8)) \\ |
| 26856-82 - 0.036" \\ | 26856-82 - 0.036" \\ | ||
| 26856-89 - 0.041" \\ | 26856-89 - 0.041" \\ | ||
| Line 50: | Line 48: | ||
| |{{:techtalk:evo:oil:umbrella_valve_by_gary_e.jpg?direct&300|}}|{{:techtalk:evo:oil:breather_baffle_tube_by_gary_e.jpg?direct&300|}}|{{:techtalk:evo:oil:86_crankcase_vent_3_by_norsexl.jpg?direct&300|}}| | |{{:techtalk:evo:oil:umbrella_valve_by_gary_e.jpg?direct&300|}}|{{:techtalk:evo:oil:breather_baffle_tube_by_gary_e.jpg?direct&300|}}|{{:techtalk:evo:oil:86_crankcase_vent_3_by_norsexl.jpg?direct&300|}}| | ||
| - | | Umbrella (check) Valves \\ L - (26856-82), R - (26856-89) ((photo by Gary E of the XLFORUM http://xlforum.net/forums/showthread.php?t=2071387&page=8)) | Breather Baffle Tube (26917-84) ((photo by Gary E of the XLFORUM http://xlforum.net/forums/showthread.php?t=2071387&page=8http://xlforum.net/forums/showthread.php?t=2071387&page=8)) | Cap, tube and umbrella ((photo by norseXL of the XLFORUM http://xlforum.net/forums/showthread.php?t=72099&page=25)) | | + | | Umbrella (check) Valves \\ L - (26856-82), R - (26856-89) ((photo by Gary E of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/195092-rigid-evo-oil-check-ball-spring/page8?t=2071387&page=8)) | Breather Baffle Tube (26917-84) ((photo by Gary E of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/195092-rigid-evo-oil-check-ball-spring/page8?t=2071387&page=8)) | Cap, tube and umbrella ((photo by norseXL of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/36799-installing-the-ultimate-crankcase-vent-%C2%93how-to%C2%94/page25?t=72099&page=25)) | |
| This looks like a good factory alternative replacement umbrella valve that comes in a replacement kit for Twin Cams. \\ | This looks like a good factory alternative replacement umbrella valve that comes in a replacement kit for Twin Cams. \\ | ||
| Line 58: | Line 56: | ||
| |{{:techtalk:evo:engmech:umbrella_valve_by_crb2855.jpg?direct&300|}}| | |{{:techtalk:evo:engmech:umbrella_valve_by_crb2855.jpg?direct&300|}}| | ||
| - | | 1999 Dyna Twin Cam style umbrella (26858-99) ((photo by crb2855 of the XLFORUM http://xlforum.net/forums/showthread.php?p=5884041#post5884041)) | | + | | 1999 Dyna Twin Cam style umbrella (26858-99) ((photo by crb2855 of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/195092-rigid-evo-oil-check-ball-spring/page6#post4484031)) | |
| |{{:techtalk:evo:oil:89_cam_cover_1_by_bryan350.jpg?direct&250|}}|{{:techtalk:evo:oil:89_cam_cover_2_by_bryan350.jpg?direct&250|}}|{{:techtalk:evo:oil:89_cam_cover_3_by_bryan350.jpg?direct&250|}}| | |{{:techtalk:evo:oil:89_cam_cover_1_by_bryan350.jpg?direct&250|}}|{{:techtalk:evo:oil:89_cam_cover_2_by_bryan350.jpg?direct&250|}}|{{:techtalk:evo:oil:89_cam_cover_3_by_bryan350.jpg?direct&250|}}| | ||
| - | | 89 cam cover with breather baffle tube attached (it should be tight but still pull out) ((photos by Bryan350 of the XLFORUM http://xlforum.net/forums/showthread.php?t=1712011)) ||| | + | | 89 cam cover with breather baffle tube attached (it should be tight but still pull out) ((photos by Bryan350 of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/frame-mount-evo-sportster-talk-1986-2003-models/159628-cam-cover-question?t=1712011)) ||| |
| ====== 1991-2003 Sportster Breather Valve ====== | ====== 1991-2003 Sportster Breather Valve ====== | ||
| Line 71: | Line 69: | ||
| * In 1991, along with the 5-speed transmission, the MoCo moved the crankcase breathing from the cam box cover outlet to breather bolts in the heads. \\ Previously, these bolts were just used to mount the carb and air cleaner to the heads. | * In 1991, along with the 5-speed transmission, the MoCo moved the crankcase breathing from the cam box cover outlet to breather bolts in the heads. \\ Previously, these bolts were just used to mount the carb and air cleaner to the heads. | ||
| - | * The new breather system uses (2) one-way umbrella valves (26856-89) placed in the rocker boxes (1 each placed on the intake side). \\ The part number was later updated to (26856-89A). \\ These expel crankcase vapors through vents in the top of the cylinder head and into the carb to be burnt. ((FoxsterUK of the XLFORUM http://xlforum.net/forums/showthread.php?t=518948&highlight=wet+sumping)) | + | * The new breather system uses (2) one-way umbrella valves (26856-89) placed in the rocker boxes (1 each placed on the intake side). \\ The part number was later updated to (26856-89A). \\ These expel crankcase vapors through vents in the top of the cylinder head and into the carb to be burnt. ((FoxsterUK of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/74149-engine-breather-101-crankcase-vent-101?t=518948&highlight=wet+sumping)) |
| * On each piston downstroke, crankcase pressure (air and oil mist) is routed up the pushrod tubes into the rocker box (bypassing the falling oil from the rocker boxes). | * On each piston downstroke, crankcase pressure (air and oil mist) is routed up the pushrod tubes into the rocker box (bypassing the falling oil from the rocker boxes). | ||
| * Collected air pressure and oil mist in each rocker box is routed up into a sealed cavity in the lower portion of the box. | * Collected air pressure and oil mist in each rocker box is routed up into a sealed cavity in the lower portion of the box. | ||
| Line 87: | Line 85: | ||
| **Installation** \\ | **Installation** \\ | ||
| - | * The middle rocker box is symmetrically cast so that it can be used on the front or rear head. \\ And, there is a spot (seemingly) for two umbrellas. ((zenfrogmaster of the XLFORUM http://xlforum.net/forums/showthread.php?t=382922)) | + | * The middle rocker box is symmetrically cast so that it can be used on the front or rear head. \\ And, there is a spot (seemingly) for two umbrellas. ((zenfrogmaster of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/frame-mount-evo-sportster-talk-1986-2003-models/62904-rubbery-like-small-cap-on-middle-rocker-cover?t=382922)) |
| - | * **However, only one umbrella is used in each middle section**. \\ (only 2 umbrella valves are used in the entire engine.) ((Graywolf of the XLFORUM http://xlforum.net/forums/showthread.php?p=5703205#post5703205)) \\ | + | * **However, only one umbrella is used in each middle section**. \\ (only 2 umbrella valves are used in the entire engine.) ((Graywolf of the XLFORUM https://www.xlforum.net/forum/forum-functions/sportsterpedia-com-admin/181086-sportsterpedia-progress/page12#post4237448)) \\ |
| * __Each umbrella is placed on the intake side on each head (only).__ | * __Each umbrella is placed on the intake side on each head (only).__ | ||
| * It is not always green as in the pic below (depends on what brand you buy). | * It is not always green as in the pic below (depends on what brand you buy). | ||
| |{{:techtalk:evo:oil:umbrella_valves_by_erik.jpg?direct&300|}}|{{:techtalk:evo:oil:umbrella_valve_by_phillober.jpg?direct&300|}}|{{:techtalk:evo:oil:umbrella_valve_locations_by_hippysmack.jpg?direct&300|}}| | |{{:techtalk:evo:oil:umbrella_valves_by_erik.jpg?direct&300|}}|{{:techtalk:evo:oil:umbrella_valve_by_phillober.jpg?direct&300|}}|{{:techtalk:evo:oil:umbrella_valve_locations_by_hippysmack.jpg?direct&300|}}| | ||
| - | | Umbrella Valve (only 1 installed per rocker box) ((photo by Eric of the XLFORUM http://xlforum.net/forums/showthread.php?t=382922)) ((photo by Phillober of the XLFORUM http://xlforum.net/forums/showthread.php?p=3345764#post3345764)) || Umbrella Valve Installed Locations ((photo by Hippysmack)) | | + | | Umbrella Valve (only 1 installed per rocker box) ((photo by Eric of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/frame-mount-evo-sportster-talk-1986-2003-models/62904-rubbery-like-small-cap-on-middle-rocker-cover?t=382922)) ((photo by Phillober of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-engine-conversions/116696-phillober-s-1250-conversion-thread-pic-heavy/page11#post2487181)) || Umbrella Valve Installed Locations ((photo by Hippysmack)) | |
| |{{:techtalk:evo:oil:head_breather_holes_1_by_hippysmack.jpg?direct&300|}}|{{:techtalk:evo:oil:head_breather_holes_2_by_hippysmack.jpg?direct&300|}}|{{:techtalk:evo:oil:head_breather_holes_3_by_hippysmack.jpg?direct&300|}}| | |{{:techtalk:evo:oil:head_breather_holes_1_by_hippysmack.jpg?direct&300|}}|{{:techtalk:evo:oil:head_breather_holes_2_by_hippysmack.jpg?direct&300|}}|{{:techtalk:evo:oil:head_breather_holes_3_by_hippysmack.jpg?direct&300|}}| | ||
| | 91-03 crankcase ventilation is done through the hole with the wire tie. ((photos by Hippysmack)) ||| | | 91-03 crankcase ventilation is done through the hole with the wire tie. ((photos by Hippysmack)) ||| | ||
| - | |||
| ====== 2004-Present Sportster Breather Valve ====== | ====== 2004-Present Sportster Breather Valve ====== | ||
| Line 108: | Line 105: | ||
| * In 2004 the MoCo made some changes to the umbrella valve configuration. \\ The umbrella was retained but now inside a plastic housing with a pre-umbrella oil separating screen. \\ Each 'breather valve' is assembled into a plastic fitting that is sealed over the outlet hole in the lower rocker box to the head breather bolt. \\ The new breather valves were also accompanied with new style hollow air cleaner mounting bolts for the pressure to escape. | * In 2004 the MoCo made some changes to the umbrella valve configuration. \\ The umbrella was retained but now inside a plastic housing with a pre-umbrella oil separating screen. \\ Each 'breather valve' is assembled into a plastic fitting that is sealed over the outlet hole in the lower rocker box to the head breather bolt. \\ The new breather valves were also accompanied with new style hollow air cleaner mounting bolts for the pressure to escape. | ||
| * The new bolts are the same thread size as previous. \\ But instead of a simple hex, it also has a shoulder past the hex for an O-ring to be fitted between the hex head and the air cleaner. | * The new bolts are the same thread size as previous. \\ But instead of a simple hex, it also has a shoulder past the hex for an O-ring to be fitted between the hex head and the air cleaner. | ||
| - | * The breathing system is functionally the same as 91-03 with the one-way umbrella valves in the rocker boxes. \\ These exit crankcase vapors through vents in the top of the cylinder head and into the carb mouth to be burnt. ((FoxsterUK of the XLFORUM http://xlforum.net/forums/showthread.php?t=518948&highlight=wet+sumping)) | + | * The breathing system is functionally the same as 1991-2003 with the one-way umbrella valves in the rocker boxes. \\ These exit crankcase vapors through vents in the top of the cylinder head and into the carb mouth to be burnt. ((FoxsterUK of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/74149-engine-breather-101-crankcase-vent-101?t=518948&highlight=wet+sumping)) |
| * On each piston downstroke, crankcase pressure (air and oil mist) is routed up the pushrod tubes into the rocker box (bypassing the falling oil from the rocker boxes). | * On each piston downstroke, crankcase pressure (air and oil mist) is routed up the pushrod tubes into the rocker box (bypassing the falling oil from the rocker boxes). | ||
| * Collected air pressure and oil mist in each rocker box is routed up into the breather valve unit in the lower portion of the box. | * Collected air pressure and oil mist in each rocker box is routed up into the breather valve unit in the lower portion of the box. | ||
| Line 126: | Line 123: | ||
| (as in there is one for the front and a different one for the rear) \\ | (as in there is one for the front and a different one for the rear) \\ | ||
| - | Each one consists of a poly fiber over a rubber flap. ((AnaChris of the XLFORUM http://xlforum.net/forums/showthread.php?t=1881344&highlight=crankcase+breather&page=2)) \\ | + | Each one consists of a poly fiber over a rubber flap. ((AnaChris of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/175336-crankcase-breather-kit-with-stock-air-cleaner/page2?t=1881344&highlight=crankcase+breather&page=2)) \\ |
| The fiber pieces are the same as the brown Scotchbrite pads that are sold in the body section of auto parts stores. \\ | The fiber pieces are the same as the brown Scotchbrite pads that are sold in the body section of auto parts stores. \\ | ||
| - | You can cut your own put them in the breather valves. They are aluminum oxide and won't hurt the engine. ((Sweet Terry Smoove of the XLFORUM http://xlforum.net/forums/showthread.php?p=5127159&highlight=rocker+box#post5127159)) \\ | + | You can cut your own put them in the breather valves. They are aluminum oxide and won't hurt the engine. ((Sweet Terry Smoove of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-motor-top-end/174693-umbrella-valve-filters-necessary?highlight=rocker+box#post5127159)) \\ |
| - | | Breather Valves ((photo by DK Custom of the XLFORUM http://xlforum.net/forums/showthread.php?t=1582019&page=11)) | View of one cut open. ((photos by Bored now of the XLFORUM http://xlforum.net/forums/showthread.php?p=5761087#post5761087)) || | + | | Breather Valves ((photo by DK Custom of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/efi-sportster-motorcycle-talk-2007-and-up/145738-sportster-winter-makeover/page11?t=1582019&page=11)) | View of one cut open. ((photos by Bored now of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-general-discussion-and-problems/197352-oil-cap-problems-bikers-choice-02-073/page2#post4317318)) || |
| |{{:techtalk:evo:oil:breather_valves_by_dk_custom.jpg?direct&300|}}|{{:techtalk:evo:engmech:04_up_breather_1_by_bored_now.jpg?direct&300|}}|{{:techtalk:evo:engmech:04_up_breather_2_by_bored_now.jpg?direct&300|}}| | |{{:techtalk:evo:oil:breather_valves_by_dk_custom.jpg?direct&300|}}|{{:techtalk:evo:engmech:04_up_breather_1_by_bored_now.jpg?direct&300|}}|{{:techtalk:evo:engmech:04_up_breather_2_by_bored_now.jpg?direct&300|}}| | ||
| - | | Oil drain hole. ((photo by dieselvette of the XLFORUM http://xlforum.net/forums/showthread.php?t=2073932&page=30)) | 2006 Breather Valves ((photos by JackAttack of the XLFORUM http://xlforum.net/forums/showthread.php?p=4435889)) || | + | | Oil drain hole. ((photo by dieselvette of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page30?t=2073932&page=30)) | 2006 Breather Valves ((photos by JackAttack of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-motor-top-end/151682-2006-top-end-disassembly-pic-heavy#post3232003)) || |
| |{{:techtalk:ref:engmech:04_up_breather_valve_2_by_dieselvette.jpg?direct&300|}}|{{:techtalk:evo:oil:06_rocker_box_removal_9_by_jackattack.jpg?direct&300|}}|{{:techtalk:evo:oil:06_rocker_box_removal_8_by_jackattack.jpg?direct&300|}}| | |{{:techtalk:ref:engmech:04_up_breather_valve_2_by_dieselvette.jpg?direct&300|}}|{{:techtalk:evo:oil:06_rocker_box_removal_9_by_jackattack.jpg?direct&300|}}|{{:techtalk:evo:oil:06_rocker_box_removal_8_by_jackattack.jpg?direct&300|}}| | ||
| - | | 2013 Breather Valves ((photos by chris_b_owens of the XLFORUM http://xlforum.net/forums/showthread.php?t=1832762&page=47)) ||| | + | | 2013 Breather Valves ((photos by chris_b_owens of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-styles/cafe-racer-sportster-motorcycle-talk/170788-my-2013-iron-883-cafe-build/page47?t=1832762&page=47)) ||| |
| |{{:techtalk:evo:oil:2013_crankcase_breather_2_by_chris_b_owens.jpg?direct&300|}}|{{:techtalk:evo:oil:2013_crankcase_breather_1_by_chris_b_owens.jpg?direct&300|}}|{{:techtalk:evo:oil:2013_crankcase_breather_4_by_chris_b_owens.jpg?direct&300|}}| | |{{:techtalk:evo:oil:2013_crankcase_breather_2_by_chris_b_owens.jpg?direct&300|}}|{{:techtalk:evo:oil:2013_crankcase_breather_1_by_chris_b_owens.jpg?direct&300|}}|{{:techtalk:evo:oil:2013_crankcase_breather_4_by_chris_b_owens.jpg?direct&300|}}| | ||
| Line 161: | Line 158: | ||
| You can see the loading of oil on the mesh in the pics below. The shelving partitions in the lower end do help separate oil from air. \\ | You can see the loading of oil on the mesh in the pics below. The shelving partitions in the lower end do help separate oil from air. \\ | ||
| - | With the 04 breather, a large portion of oil that gets past the umbrella can drain from the separator "ladders" back into the rocker box. \\ | + | With the 2004-up breather, a large portion of oil that gets past the umbrella can drain from the separator "ladders" back into the rocker box. \\ |
| And some, usually in the form of mist will blow into the air cleaner. \\ | And some, usually in the form of mist will blow into the air cleaner. \\ | ||
| Any oil that gets past the umbrella with the Buell breather will blow out the vent hose routed into the air filter. \\ | Any oil that gets past the umbrella with the Buell breather will blow out the vent hose routed into the air filter. \\ | ||
| - | After some time it forms a puddle of condensed oil inside the airbox under the air filter. ((TPEHAK of the XLFORUM http://xlforum.net/forums/showthread.php?t=2073932&page=93)) \\ | + | After some time it forms a puddle of condensed oil inside the airbox under the air filter. ((TPEHAK of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page93?t=2073932&page=93)) \\ |
| - | {{:techtalk:evo:engmech:breather_valve_-_buell_17607-00y_by_tpehak_annotated_by_hippysmack.jpg?direct&500|}} ((drawing by TPEHAK of the XLFORUM http://xlforum.net/forums/showthread.php?t=2073932&page=93)) {{:techtalk:evo:engmech:breather_valve_-_buell_17607-00y_pic1_by_tpehak_annotated_by_hippysmack.jpg?direct&400|}} ((photo by TPEHAK of the XLFORUM http://xlforum.net/forums/showthread.php?t=2073932&page=93)) \\ | + | {{:techtalk:evo:engmech:breather_valve_-_buell_17607-00y_by_tpehak_annotated_by_hippysmack.jpg?direct&500|}} ((drawing by TPEHAK of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page93?t=2073932&page=93)) {{:techtalk:evo:engmech:breather_valve_-_buell_17607-00y_pic1_by_tpehak_annotated_by_hippysmack.jpg?direct&400|}} ((photo by TPEHAK of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page93?t=2073932&page=93)) \\ |
| - | {{:techtalk:evo:engmech:breather_valve_-_buell_17607-00y_pic2_by_tpehak_annotated_by_hippysmack.jpg?direct&400|}} ((photo by TPEHAK of the XLFORUM http://xlforum.net/forums/showthread.php?t=2073932&page=93)) | + | {{:techtalk:evo:engmech:breather_valve_-_buell_17607-00y_pic2_by_tpehak_annotated_by_hippysmack.jpg?direct&400|}} ((photo by TPEHAK of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page93?t=2073932&page=93)) |
| - | {{:techtalk:evo:engmech:breather_valve_-_buell_17607-00y_pic3_by_tpehak_annotated_by_hippysmack.jpg?direct&400|}} ((photo by TPEHAK of the XLFORUM http://xlforum.net/forums/showthread.php?t=2073932&page=93)) \\ | + | {{:techtalk:evo:engmech:breather_valve_-_buell_17607-00y_pic3_by_tpehak_annotated_by_hippysmack.jpg?direct&400|}} ((photo by TPEHAK of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page93?t=2073932&page=93)) \\ |
| ====== Check the breather to gasket seal ====== | ====== Check the breather to gasket seal ====== | ||
| - | There is an anomaly when it comes to the seal around the stock breather port under the rocker box. ((dieselvette of the XLFORUM http://xlforum.net/forums/showthread.php?p=5769573#post5769573))\\ | + | There is an anomaly when it comes to the seal around the stock breather port under the rocker box. ((dieselvette of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page46#post4327896))\\ |
| The rocker box cover gasket is part of the seal for the breather port. \\ | The rocker box cover gasket is part of the seal for the breather port. \\ | ||
| It's possible to make a mistake when installing the breathers into aftermarket gaskets and end up with oil puking out the breathers. \\ | It's possible to make a mistake when installing the breathers into aftermarket gaskets and end up with oil puking out the breathers. \\ | ||
| Line 184: | Line 181: | ||
| Also there is a bump to take up extra space next to the umbrella housing and it fits nicely in the hole of the gasket. \\ | Also there is a bump to take up extra space next to the umbrella housing and it fits nicely in the hole of the gasket. \\ | ||
| - | {{:techtalk:evo:engmech:oem_gasket_1_by_dieselvette.jpg?direct&300|}} ((photo by dieselvette of the XLFORUM http://xlforum.net/forums/showthread.php?p=5769573#post5769573)) {{:techtalk:evo:engmech:oem_gasket_2_by_dieselvette.jpg?direct&300|}} ((photo by dieselvette of the XLFORUM http://xlforum.net/forums/showthread.php?p=5769573#post5769573)) | + | {{:techtalk:evo:engmech:oem_gasket_1_by_dieselvette.jpg?direct&300|}} ((photo by dieselvette of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page46#post4327896)) {{:techtalk:evo:engmech:oem_gasket_2_by_dieselvette.jpg?direct&300|}} ((photo by dieselvette of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page46#post4327896)) |
| **Using Cometic Rocker Box Gaskets**: \\ | **Using Cometic Rocker Box Gaskets**: \\ | ||
| Line 191: | Line 188: | ||
| To make this seal properly you would need the orange seal but you would only have the orange seal if you bought new breathers also. \\ | To make this seal properly you would need the orange seal but you would only have the orange seal if you bought new breathers also. \\ | ||
| - | {{:techtalk:evo:engmech:cometic_gasket_1_by_dieselvette.jpg?direct&300|}} ((photo by dieselvette of the XLFORUM http://xlforum.net/forums/showthread.php?p=5769573#post5769573)) {{:techtalk:evo:engmech:cometic_gasket_2_by_dieselvette.jpg?direct&300|}} ((photo by dieselvette of the XLFORUM http://xlforum.net/forums/showthread.php?p=5769573#post5769573)) | + | {{:techtalk:evo:engmech:cometic_gasket_1_by_dieselvette.jpg?direct&300|}} ((photo by dieselvette of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page46#post4327896)) {{:techtalk:evo:engmech:cometic_gasket_2_by_dieselvette.jpg?direct&300|}} ((photo by dieselvette of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page46#post4327896)) |
| ====== Head Breather Bolts ====== | ====== Head Breather Bolts ====== | ||
| Line 204: | Line 200: | ||
| Without the hole through the bolts, the engine can't breathe. \\ | Without the hole through the bolts, the engine can't breathe. \\ | ||
| - | The size of the orifice in the hollow head breather bolts makes the crankcase pressure rise higher (or lower) in the process of expelling the gas. ((aswracing of the XLFORUM http://xlforum.net/forums/showthread.php?p=4050323&highlight=breather+bolts#post4050323)) \\ | + | The size of the orifice in the hollow head breather bolts makes the crankcase pressure rise higher (or lower) in the process of expelling the gas. ((aswracing of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/frame-mount-evo-sportster-talk-1986-2003-models/138864-why-do-screamin-eagle-breathers-have-pin-hole-ends?highlight=breather+bolts#post2960323)) \\ |
| - | + | ||
| - | == 91-03 == | + | |
| + | == 1991-2003 == | ||
| 91-03 breather bolts. \\ Outside threads are 1/2" x 13 (hole through the middle is 5/6" nominal). \\ | 91-03 breather bolts. \\ Outside threads are 1/2" x 13 (hole through the middle is 5/6" nominal). \\ | ||
| {{:techtalk:evo:carb:91-03_breather_bolts_1_by_hippysmack.jpg?direct&300|}} ((photo by Hippysmack)) {{:techtalk:evo:carb:91-03_breather_bolts_2_by_hippysmack.jpg?direct&300|}} ((photo by Hippysmack)) | {{:techtalk:evo:carb:91-03_breather_bolts_1_by_hippysmack.jpg?direct&300|}} ((photo by Hippysmack)) {{:techtalk:evo:carb:91-03_breather_bolts_2_by_hippysmack.jpg?direct&300|}} ((photo by Hippysmack)) | ||
| - | == 04 and Up == | + | == 2004 and Up == |
| Crankcase pressure was increased in 2004 by several means. \\ | Crankcase pressure was increased in 2004 by several means. \\ | ||
| One of which was the reduction of the hole size in the breather bolts on the engine side (more restriction). \\ | One of which was the reduction of the hole size in the breather bolts on the engine side (more restriction). \\ | ||
| Line 218: | Line 212: | ||
| They also allow the air to leave the vents at a faster rate. \\ | They also allow the air to leave the vents at a faster rate. \\ | ||
| - | 04+ breather bolts. \\ Outside threads are 1/2" x 13 (2 different sizes thru the middle - nominally 1/16" (1.5875 mm) in the rear and 5/16" in the front). ((tomcat of the XLFORUM http://xlforum.net/forums/showthread.php?t=2073932&page=19)) ((Folkie of the XLFORUM http://xlforum.net/forums/showthread.php?t=2073932&page=22)) ((http://xlforum.net/forums/showthread.php?p=5756327#post5756327)) \\ | + | 04+ breather bolts. \\ Outside threads are 1/2" x 13 (2 different sizes thru the middle - nominally 1/16" (1.5875 mm) in the rear and 5/16" in the front). ((tomcat of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page19?t=2073932&page=19)) ((Folkie of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-motor-engine/sportster-motorcycle-bottom-end/197307-sportster-crankcase-pressure-engine-breathing-wetsumping-and-mods/page22?t=2073932&page=22)) ((https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/28874-stock-air-cleaner-box-modifications/page20#post4310316)) \\ |
| - | {{:techtalk:evo:engmech:04_up_breather_bolt_3_by_folkie.jpg?direct&300|}} ((photo by Folkie of the XLFORUM http://xlforum.net/forums/showthread.php?p=5756327#post5756327)) {{:techtalk:evo:engmech:04_up_breather_bolt_2_by_folkie.jpg?direct&300|}} ((photo by Folkie of the XLFORUM http://xlforum.net/forums/showthread.php?p=5756327#post5756327)) {{:techtalk:evo:engmech:04_up_breather_bolt_1_by_folkie.jpg?direct&300|}} ((photo by Folkie of the XLFORUM http://xlforum.net/forums/showthread.php?p=5756327#post5756327)) | + | {{:techtalk:evo:engmech:04_up_breather_bolt_3_by_folkie.jpg?direct&300|}} ((photo by Folkie of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/28874-stock-air-cleaner-box-modifications/page20#post4310316)) {{:techtalk:evo:engmech:04_up_breather_bolt_2_by_folkie.jpg?direct&300|}} ((photo by Folkie of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/28874-stock-air-cleaner-box-modifications/page20#post4310316)) {{:techtalk:evo:engmech:04_up_breather_bolt_1_by_folkie.jpg?direct&300|}} ((photo by Folkie of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-intake-and-exhaust/sportster-motorcycle-air-intake-carburetor-efi-fuel-and-exhaust/28874-stock-air-cleaner-box-modifications/page20#post4310316)) |
| - | If you know someone with a lathe, you can have some stainless steel breather bolts made. ((photos by Folkie of the XLFORUM http://xlforum.net/forums/showthread.php?t=2073497&highlight=oil+level&page=7)) \\ | + | If you know someone with a lathe, you can have some stainless steel breather bolts made. ((photos by Folkie of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-general-discussion-and-problems/196939-oil-in-air-cleaner/page7?t=2073497&highlight=oil+level&page=7)) \\ |
| {{:techtalk:evo:engmech:stainless-steel-breather-bolts-1_by_folkie.jpg?direct&300|}} {{:techtalk:evo:engmech:stainless-steel-breather-bolts-2_by_folkie.jpg?direct&300|}} | {{:techtalk:evo:engmech:stainless-steel-breather-bolts-1_by_folkie.jpg?direct&300|}} {{:techtalk:evo:engmech:stainless-steel-breather-bolts-2_by_folkie.jpg?direct&300|}} | ||
| Line 250: | Line 244: | ||
| The oil on the soaked mesh can vapor off if it doesn't cool on shutdown and gunk up there. If it gunks up, the mesh should be pulled and cleaned or replaced. \\ | The oil on the soaked mesh can vapor off if it doesn't cool on shutdown and gunk up there. If it gunks up, the mesh should be pulled and cleaned or replaced. \\ | ||
| + | ===== Test for air flow at the vent ===== | ||
| You can verify a stopped up breather valve by "feeling" for air moving from the breather vent(s) with the air cleaner off, finger near each vent. \\ | You can verify a stopped up breather valve by "feeling" for air moving from the breather vent(s) with the air cleaner off, finger near each vent. \\ | ||
| As long as you have know air is moving, then the breather valve isn't stopped up. \\ | As long as you have know air is moving, then the breather valve isn't stopped up. \\ | ||
| Line 260: | Line 255: | ||
| However, with the air cleaner off and a finger placed into the vent air stream; \\ | However, with the air cleaner off and a finger placed into the vent air stream; \\ | ||
| - | * The exiting air from the vent is being sped up from the umbrella chamber to the vent. \\ This will pressurize the exit vent, hence the "FEEL" of pressure. ((bustert of the XLFORUM http://xlforum.net/forums/showthread.php?t=2081302)) \\ When the flow stops abruptly (pulse finishes), there is an instant void that is filled with atmospheric pressure. \\ Hence the "FEEL" of return flow. | + | * The exiting air from the vent is being sped up from the umbrella chamber to the vent. \\ This will pressurize the exit vent, hence the "FEEL" of pressure. ((bustert of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-general-discussion-and-problems/203992-only-one-breather-bolt-breathing?t=2081302)) \\ When the flow stops abruptly (pulse finishes), there is an instant void that is filled with atmospheric pressure. \\ Hence the "FEEL" of return flow. |
| * A new flexible umbrella is designed to allow pressure to move out, not in. \\ However, outside air can still enter through the oil drain back hole on engine vacuum cycles. | * A new flexible umbrella is designed to allow pressure to move out, not in. \\ However, outside air can still enter through the oil drain back hole on engine vacuum cycles. | ||
| * 1986-up breather valves also incorporate an oil drain back hole for engine vacuum to pull separated oil from mist back into the motor. \\ The drain hole is past the umbrella between it and the outlet air vent. The drain hole is not controlled by the umbrella but rather engine vacuum. \\ So after the drain hole empties separated oil and is still under vacuum at that split second, holding a finger to the vent may feel a slight vacuum. | * 1986-up breather valves also incorporate an oil drain back hole for engine vacuum to pull separated oil from mist back into the motor. \\ The drain hole is past the umbrella between it and the outlet air vent. The drain hole is not controlled by the umbrella but rather engine vacuum. \\ So after the drain hole empties separated oil and is still under vacuum at that split second, holding a finger to the vent may feel a slight vacuum. | ||
| Line 274: | Line 269: | ||
| {{:techtalk:evo:engmech:2004-up_breather_vent_-_how_air_vacuum_closes_it_by_hippysmack.png?direct&500|}} ((drawing by Hippysmack)) \\ | {{:techtalk:evo:engmech:2004-up_breather_vent_-_how_air_vacuum_closes_it_by_hippysmack.png?direct&500|}} ((drawing by Hippysmack)) \\ | ||
| + | |||
| + | ===== Blow testing through the vent ===== | ||
| + | Since it's a one-way valve, air should go out but not come back in (past the umbrella itself). \\ | ||
| + | |||
| + | Before you position the hose, you can use a bit of clean pipe and blow gently through the breather. ((Four Speed of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/frame-mount-evo-sportster-talk-1986-2003-models/196577-1987-883-breather-bolts-are-different#post4295094)) \\ | ||
| + | It should close the valve and stop air flow (if you use a quick hard breath). \\ | ||
| + | However, blowing slow and gently will allow a small amount of breath to go into the engine through the tiny oil drainback hole. \\ | ||
| + | You may have to find an aftermarket replacement if the valve is shot and OEM replacements are hard to come by. \\ | ||
| + | The 5 speed (rocker box) umbrellas are smaller than the 4 speed (cam cover) umbrellas and these won't interchange. \\ | ||
| + | |||
| \\ | \\ | ||
