Differences

This shows you the differences between two versions of the page.

--- techtalk:ih:engmech07 [2020/10/23 21:12]
hippysmack [1956-1959 Breather Valve]
+++ techtalk:ih:engmech07 [2022/04/08 21:09]
hippysmack [1979-E1982 Breather Valve]
@@ Line 6: / Line 6: @@
   * [[techtalk:ref:engmech04k|Breather Valves (1957-Up)]] (list of breather valve changes)
   * [[techtalk:ref:engmech07g|Further Study of the Timed Breather Valve]]
+  * [[techtalk:ref:engmech07i|Dissecting the 77-78 Breather (foo-foo) Valve (24634-77)]]
   * [[techtalk:ref:engmech07s|XR-750 8-Ball Breather Valve]]
   * [[techtalk:ref:engmech05|Breather Venting / Relocation]]
@@ Line 16: / Line 17: @@
 \\
 ===== Sub Documents =====
   * [[techtalk:ih:engmech07a|Timing the 76< Breather Valve]]
@@ Line 52: / Line 54: @@
     * Slot in pump body: .345"
     * Slot in pump gear: .375"
+  * 180° of vacuum from front (BDC) to front (TDC).
 ===== 1972-1976 Breather Valve =====
@@ Line 57: / Line 60: @@
   * Breather timing and duration:
     * Opens 20°-25° (ATDC) and closes 85°-90° (ABDC). ((thefrenchowl of the XLFORUM http://xlforum.net/forums/showthread.php?t=2077939&page=2))
-  * Duration - 245°(and 50% less vacuum than 71< on upstroke).
+  * Duration - 245°.
  * Slot widths: ((chevelle of the XLFORUM http://xlforum.net/forums/showthread.php?t=989934&page=2))
     * Slot in pump body: .345"
     * Slot in pump gear: .625"
+    * 90° of vacuum from 90° (ABDC) to front (TDC).
+===== Oil Deflector / Separator Bushing Assembly (1952-1962) =====
+AKA, (spring loaded top hat) \\
+-1962 K Models and Sportsters used a drive gear on the generator with an integral oil slinger (daisy wheel) on the end. \\
+Oil gets slung back into the gearcase and air is sent thru the oil deflector bushing and out the cover by way of the breather tube. \\
+See more on the generator gear at the bottom of this page. \\
+The oil deflector bushing consists of 2 pieces with the second being a brass oil seal insert "top hat". \\
+A spring (25287-37) sits under the top hat in the bushing bore. \\
+The assembly is pressed into the front of the cover with the brass being spring loaded against the generator "daisy cutter" gear. \\
+The brass part is an oil seal and the daisy cutter separates air from oil sending the air into the deflector bushing then out the breather tube. \\
+The brass top hat has a spring under pushing toward the generator and the top hat has limited action keeping it inside the bushing. \\
+Looking at the brass part, you can see how the spring catches on the inward bent tabs. ((Dr Dick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1861965)) \\
+The brass stays keyed to the steel at full spring compression and "plunges" in and out under the spring pressure. \\
+The outward bent tangs do 2 things. \\
+  * They keep the brass hat and spring captive in the cover upon generator removal.
+  * More importantly, they key the brass to the steel to prevent the brass from rotating with the generator gear. \\ The brass is unable to rotate by the tangs keying into the slots.
+From 1952-1963, the bushing/oil seal assembly was sold as a unit with both pieces being sold under part# (25265-52). \\
+In 1964, the bushing was still sold under part# (25265-52) and the oil seal "top hat" was sold separately under part# (25270-52). \\
+**Inspection**: \\
+Check the operation of the oil separator bushing assembly. \\
+The spring should have free action and be fully extended in the gearcase cover. \\
+{{:techtalk:ih:engmech:1952-1962_k_model-sportster_breather_oil_separator_bushing_assembly_25265-52_by_jrsvintageharley1990.jpg?direct&300|}} ((photo courtesy of Ebay seller, jrsvintageharley1990. [[https://www.ebay.com/str/jrsvintageharleyparts?_trksid=p2047675.l2563|Link to Ebay Store]]  )) {{:techtalk:ih:engmech:1952-1962_k_model-sportster_oil_deflector_bushing_installed_by_panknuckpartsandtreasures.jpg?direct&300|}} ((photos courtesy of Ebay seller, panknuckpartsandtreasures. [[https://www.ebay.com/sch/panknuckpartsandtreasures/m.html?_nkw=&_armrs=1&_ipg=&_from=|Link to Ebay Store]] )) \\
+===== Oil Separator Deflector (1963-1978) =====
+{{:techtalk:ih:engmech:1963-1978_sportster_cam_cover_oil_deflector_25265-63_by_jrsvintageharley1990.jpg?direct&300|}} ((photos courtesy of Ebay seller, jrsvintageharley1990. [[https://www.ebay.com/str/jrsvintageharleyparts?_trksid=p2047675.l2563|Link to Ebay Store]]  )) \\
 ====== One Way Breather Valve (77-85) ======
 The one way breather style system is more like a car PCV system. ((mrmom9r of the XLFORUM http://xlforum.net/forums/showthread.php?t=1204854&page=4)) Unlike an auto PCV, a Sportster has a faster acting type one way valve. \\
@@ Line 87: / Line 120: @@
 -85 engines vent through a valve in the cam cover. \\
 There were several changes made of the valve itself, but they operate on the same principle., a one way breather valve. \\
+Where 76< engine crankcase volume is the simply the crankcase itself, 77> engines have the added volume of the gearcase as well. \\
+With the non-timed breather valve closing at BDC, the bottom end volume has 180° of vacuum starting from front (BDC) to front (TDC). \\
 ===== 1977-1978 Breather Valve =====
@@ Line 110: / Line 145: @@
       * It's a possible option for the 77-78 foofoo valve  to be replaced with an external breather valve. \\ If you want to go this route, remove the internal valve as it will also change crankcase pressure with 2 valves in line. \\ Then, you might want to consider installing something like the external Krankvent or others. \\ [[techtalk:ref:engmech05d|Click here]] to see the Converting Head Breathers to Cam Chest Breather page in the Sportsterpedia. \\ That page is for an Evo conversion to cam chest breathing but the Krankvent and plumbing is shown. \\ You can also review this page in the Sportsterpedia  [[techtalk:ref:engmech05|Breather Venting / Relocation]] (especially the sub documents at the top of the page)
-| 77 Cam Cover Breather Compartment. ((photo by joynny77 of the XLFORUM http://xlforum.net/forums/showthread.php?t=610444&page=4)) |
+| 77 Cam Cover Breather Compartment. ((photo by joynny77 of the XLFORUM http://xlforum.net/forums/showthread.php?t=610444&page=4)) |  See "Dissecting the 77-78 Breather (foo-foo) Valve (24634-77)" for more pics and dims. ((photos by Hippysmack))  ||
-|{{:techtalk:ih:engmech:1977_crankcase_breather_compartment_by_johnny77.jpg?direct&300|}}|
+|{{:techtalk:ih:engmech:1977_crankcase_breather_compartment_by_johnny77.jpg?direct&300|}}|{{:techtalk:ref:engmech:77-78_xl_foofoo_valve_24634-77_pic1_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:engmech:77-78_xl_foofoo_valve_24634-77_pic12_by_hippysmack.jpg?direct&300|}}|
 |  77-78 Crankcase Breather Valve ((photo by Hopper of the XLFORUM http://xlforum.net/forums/showthread.php?p=1960632))  |||
@@ Line 131: / Line 166: @@
     * The breather valve is a simple reed valve with a flap made of spring steel over a hole. \\ Unless it's visibly damaged, there's no reason to mess with it. ((BigMek of the XLFORUM http://xlforum.net/forums/showthread.php?p=5843330)) \\ If it stops up, you can try and spray some WD-40 in the hole to clear it.
   * **Removal**:
-    * The reed cam be removed with a standard bushing / bearing puller  with a 5/8".
+    * The reed can be removed with a standard bushing / bearing puller  with a 5/8".
   * **Replacement options / mods**:
     * In L1982, a new style crankcase breather valve was used in production. \\ The breather valve kit (26909-79A), which is functionally more durable and quieter than the early style reed valve, will fit 1979-E82 models. \\ The late style breather valve incorporates a rubber umbrella valve attached to the base plate along with a larger diameter oil slinger washer. \\ The oil slinger washer is bigger (1-3/4" OD). \\ These parts, used together, will replace the early style reed valve assembly and smaller diameter oil separator washer. \\
@@ Line 137: / Line 172: @@
     * [[techtalk:ref:engmech05i#refengine_mechanicals_-_sub-05i|Click here]] to see the page on Adding a Secondary Vent Hose at the 6:00 Position. \\ This mod has been done with agreeable results to improve breathing.
-Cam Cover Breather Compartment (with the rubber umbrella valve upgrade). ((photo by joynny77 of the XLFORUM http://xlforum.net/forums/showthread.php?t=610444&page=4)) \\
+Here's the reed valve as installed. \\
-{{:techtalk:ih:engmech:1981_crankcase_breather_compartment_w_update_rubber_valve_by_johnny77.jpg?direct&300|}} \\
+{{:techtalk:ih:engmech:79_breather_valve_by_tobybott.jpg?direct&350|}} ((photo by tobybott of the XLFORUM http://xlforum.net/forums/showthread.php?p=982127&highlight=breather#post982127)) \\
-Here's the reed valve and the back side. \\
+Here is the reed valve assembly  front and back side. \\
-{{:techtalk:ih:engmech:79_breather_valve_by_tobybott.jpg?direct&350|}} ((photo by tobybott of the XLFORUM http://xlforum.net/forums/showthread.php?p=982127&highlight=breather#post982127)) {{:techtalk:ih:engmech:reed_valve_by_lodkolv.jpg?direct&300|}} ((photo by lodkolv of the XLFORUM http://xlforum.net/forums/showthread.php?t=113861&highlight=breather&page=2)) \\
+{{:techtalk:ih:engmech:1979-e1982_sportster_reed_type_breather_valve_26909-79_by_bikersnos_pic2.jpg?direct&300|}} ((photo courtesy of BIKERSNOS.com. [[https://www.ebay.com/str/bikersnos?_trksid=p2047675.m3561.l2563|Link to Ebay Store]] ))
+{{:techtalk:ih:engmech:1979-e1982_sportster_reed_type_breather_valve_26909-79_by_bikersnos_pic1.jpg?direct&300|}} ((photo courtesy of BIKERSNOS.com. [[https://www.ebay.com/str/bikersnos?_trksid=p2047675.m3561.l2563|Link to Ebay Store]] )) \\
+\\
+=== L1982 Upgrade ===
+(Left) - E82 cover with the breather removed showing compartment below. ((photo by wlkilmer of the XLFORUM)) \\
+(Right) - 81 Cam Cover Breather Compartment (with the rubber umbrella valve upgrade). ((photo by joynny77 of the XLFORUM http://xlforum.net/forums/showthread.php?t=610444&page=4)) \\
+{{:techtalk:ih:engmech:1982_breather_compartment_oil_drainback_hole_by_wlkilmer.jpg?direct&300|}} {{:techtalk:ih:engmech:1981_crankcase_breather_compartment_w_update_rubber_valve_by_johnny77.jpg?direct&300|}} \\
 ===== L1982-E1984 Breather Valve =====
@@ Line 148: / Line 191: @@
     * The crankcase breather valve was redesigned to incorporate a rubber umbrella valve attached to a metal disc installed in the base plate. \\ (along with a larger diameter 1-3/4" O.D. slinger washer)
+{{:techtalk:ih:engmech:83_cam_cover_breather_valve_by_hippysmack.jpg?direct&300|}} ((photo by Hippysmack)) \\
 ===== L1984-1990 Breather Valve =====
@@ Line 153: / Line 197: @@
     * The generator was moved and an oil filter was mounted in it's place. The oil slinger system was deleted for L84-up models.
     * The crankcase breather valve was redesigned to incorporate a baffle tube assembly (26917-84) with a rubber umbrella valve inside it.
+The pic on the left shows the breather line coming out at the 10 o'clock position going up to the air cleaner. \\
+The pic on the right is of an 85 cam cover with the foofoo valve (baffle tube) off to the left of it. \\
+{{:techtalk:ih:engmech:85_foofoo_2_by_spamer80.jpg?direct&300|}} ((photo by spammer80 of the XLFORUM))  {{:techtalk:ih:oil:85_cam_cover_1_by_billeuze.jpg?direct&300|}} ((photo by billeuze of the XLFORUM http://xlforum.net/forums/showthread.php?t=1103082))
+**Umbrella check valve**: ((Gary E of the XLFORUM http://xlforum.net/forums/showthread.php?t=2071387&page=8)) \\
+Outside diameter: \\
+-82 - 1.25" \\
+Edge thickness (1/8" in average): ((Gary E of the XLFORUM http://xlforum.net/forums/showthread.php?t=2071387&page=8)) \\
+-82 - 0.036" \\
+The pic below shows the left side (filter side) that faces into the cam box. \\
+It's center inside diameter is slightly larger than the 1.25" OD (-82) umbrella valve. \\
+The two 'C' shaped slots that do the breathing have an OD of 1". \\
+|{{:techtalk:evo:oil:breather_baffle_tube_by_gary_e.jpg?direct&300|}}|{{:techtalk:evo:oil:86_crankcase_vent_3_by_norsexl.jpg?direct&300|}}|
+|  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))  |
 ===== 1979-1990 Breather Valve Replacement Options / Mods =====
@@ Line 159: / Line 221: @@
     * [[techtalk:ref:engmech05i#refengine_mechanicals_-_sub-05i|Click here]] to see the page on Adding a Secondary Vent Hose at the 6:00 Position. \\ This mod has been done with agreeable results to improve breathing.
-The pic on the left shows the breather line coming out at the 10 o'clock position going up to the air cleaner. \\
-The pic on the right is of an 85 cam cover with the foofoo valve (baffle tube) off to the left of it. \\
-{{:techtalk:ih:engmech:85_foofoo_2_by_spamer80.jpg?direct&300|}} ((photo by spammer80 of the XLFORUM))  {{:techtalk:ih:oil:85_cam_cover_1_by_billeuze.jpg?direct&300|}} ((photo by billeuze of the XLFORUM http://xlforum.net/forums/showthread.php?t=1103082))
 ====== Oil Slinger ======
@@ Line 173: / Line 231: @@
 It spins oil away from the breather hole by centrifugal force and separates the oil mist in suspension with the exhausting air. \\
-**Factory Oil Slingers**: ((Dr Dick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1660412&page=3)) ((Moon Wolf of the XLFORUM http://xlforum.net/forums/showthread.php?p=2195143#post2195143)) ((thefrenchowl of the XLFORUM http://xlforum.net/forums/showthread.php?p=2195143#post2195143)) \\
+  * **1952-1962 K/KH/Sportsters** used a drive gear with an integral oil slinger (daisy wheel) on the end and pinned to the generator shaft. \\ It looks like a gear with a tinker toy connector glued on the end. It's a lathe machined affair combined with a spring loaded sleeve in the cover. \\ Just get rid of the timing cover sliding bush/spring if you want to upgrade to the big washer instead. ((thefrenchowl of the XLFORUM http://xlforum.net/forums/showthread.php?p=2195143#post2195143)) \\ The sliding bushing assembly makes the early slinger works as a "labyrinth" since the air has to travel through its center to get out. \\ That's why it's a better set up than the simpler washer setup. It doesn't allow for any oil to escape except if your engine is totally wetsumped. \\ But the early slinger will work without the sliding bushing, just not as good. \\ And you can't use the sliding bushing with the washer setup.
-  * **1957** used the model 52 generator, no nut or washer, and a daisy wheel gear (31071-52A) pinned to the generator shaft.
+    * **K and KH Models** used gear (31071-52). \\
-  * **1958-1962** used a daisy wheel gear (31071-58), an integral slinger / genny gear bolted to the shaft. \\ It looks like a gear with a tinker toy connector glued on the end. \\ It's a lathe machined affair combined with a spring loaded sleeve in the cover. \\ These are great gears but no one repops them and they are expensive and hard to find.
+    * **1957 XL Sportster** used gear (31071-52A) with no nut or washer.
-    * Just get rid of the timing cover sliding bush/spring if you want to upgrade to the big washer instead. ((thefrenchowl of the XLFORUM http://xlforum.net/forums/showthread.php?p=2195143#post2195143)) \\ The sliding bushing assembly makes the early slinger works as a "labyrinth" since the air has to travel through its center to get out. \\ That's why it's a better set up than the simpler washer setup. It doesn't allow for any oil to escape except if your engine is totally wetsumped. \\ But the early slinger will work without the sliding bushing, just not as good. \\ And you can't use the sliding bushing with the washer setup.
+  * **1958-1962 Sportsters** also used a daisy wheel gear (31071-58) but now bolted to the generator shaft.
-  * **L1962-1978** used a more standard looking 14T gear (31073-63) used with a 1-5/8" washer style slinger (31067-63). \\ Not as good but a lot cheaper to make. The washer itself looks to be just a normal fender washer. \\ You may find an in use washer with grooves stamped in it. Grooves are an old mod done by owners/wrenches (not the factory). \\ It is large enough in diameter to make installing the generator tricky at times. \\ 5/16" fender washers come in 3 sizes. 1.375" (common), 1.500" (hard to find), 1.625" (real hard to find). \\ OEM is 1.625" although the 1.500" washer usually works fine. The 1.375" washer may pass more oil out the vent than the bigger ones. \\
+  * **L1962-1978 Sportsters** used a more standard looking 14T gear (31073-63) used with a 1-5/8" washer style slinger (31067-63). \\ Not as good but a lot cheaper to make. The washer itself looks to be just a normal fender washer. \\ You may find an in use washer with grooves stamped in it. Grooves are an old mod done by owners/wrenches (not the factory). \\ It is large enough in diameter to make installing the generator tricky at times. \\ 5/16" fender washers come in 3 sizes. 1.375" (common), 1.500" (hard to find), 1.625" (real hard to find). \\ OEM is 1.625" although the 1.500" washer usually works fine. The 1.375" washer may pass more oil out the vent than the bigger ones. \\
-  * **1979-1981** used gear (31073-63A) with the 1-5/8" slinger washer (31067-63).
+  * **1979-1981 Sportsters** used gear (31073-63A) with the 1-5/8" slinger washer (31067-63).
-  * **1982-E1984** used the same gear (31073-63A) with a 1-3/4" slinger washer (31066-82) to accommodate the larger crankcase breather valve.
+  * **1982-E1984 Sportsters** used the same gear (31073-63A) with a 1-3/4" slinger washer (31066-82) to accommodate the larger crankcase breather valve.
 To inspect or replace the slinger washer, remove the two bolts from the cam cover that hold the generator. ((randy3934 of the XLFORUM http://xlforum.net/forums/showthread.php?t=1651226&highlight=slinger&page=2)) \\
@@ Line 188: / Line 246: @@
 If it is loose, you can probably remove it, clean up the boss with brake cleaner and reinstall the bushing with Loctite or epoxy. ((shovithead of the XLFORUM http://xlforum.net/forums/showthread.php?t=1651226&highlight=slinger&page=3)) \\
-|  58-62 generator gear / oil slinger (31071-58) ((photo by Dr Dick of the XLFORUM http://xlforum.net/forums/showthread.php?p=5100777#post5100777))  |  63-later oil slinger washer (31067-63) ((photo by papphammar of the XLFORUM http://xlforum.net/forums/showthread.php?t=495298))  |
+|1952-1956 K/KH or 1957 XL Sportster (pinned) \\ Generator Drive Gear / Oil Slinger ((photo courtesy of Ebay seller, JDVintagellc. [[https://www.ebay.com/str/jdvintagellc?_trksid=p2047675.l2563|Link to Ebay Store]] ))|1958-1962 Sportster (threaded) \\ Generator Gear / Oil Slinger (31071-58) ((photo by Dr Dick of the XLFORUM http://xlforum.net/forums/showthread.php?p=5100777#post5100777))|1963-Later Oil Slinger Washer (31067-63) ((photo by papphammar of the XLFORUM http://xlforum.net/forums/showthread.php?t=495298))|
-|{{:techtalk:ih:engmech:generator_drive_gear_31071-58_by_dr_dick.jpg?direct&300|}}|{{:techtalk:ih:engmech:oil_slinger_on_76_xlch_by_papphammar.jpg?direct&300|}}|
+|{{:techtalk:ih:elec:generator_drive_gear_k-kh_or_xl_pic2_by_j-dvintage.jpg?direct&300|}}|{{:techtalk:ih:engmech:generator_drive_gear_31071-58_by_dr_dick.jpg?direct&300|}}|{{:techtalk:ih:engmech:oil_slinger_on_76_xlch_by_papphammar.jpg?direct&300|}}|

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