Differences

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--- techtalk:ih:oil01u [2020/08/08 00:36]
hippysmack
+++ techtalk:ih:oil01u [2021/02/19 15:52]
hippysmack [Venting the Primary]
@@ Line 5: / Line 5: @@
 \\
 ====== Plug it or Not? ======
+See [[techtalk:ih:oil01t|Further Study of the Transfer Valve Operation and Affects of Plugging the Valve]] in the Sportsterpedia. \\
 ====== Removing the Transfer Valve ======
@@ Line 10: / Line 12: @@
 ====== Plugging the Valve / Hole ======
+**Note**: If you plug the transfer valve, it is advisable to also add a transmission / primary vent as well. \\
+The transfer valve has a dual function of moving out excess oil leakage from sit sumping and venting the primary compartment to the crankcase. \\
+(where the air is expelled along with crankcase pressure out the breather vent) \\
+Without a vent once the transfer valve is plugged off, primary venting is severely hindered if not bottled up entirely. \\
+It is possible to blow the sprocket seal, starter gasket or primary gasket without a vent to atmosphere over the primary or tranny. \\
-When plugging the transfer valve; \\
-With the dual function of moving excess oil leakage from sit sumping and venting primary compartment air, consensus says to also install a primary vent as well. \\
 See Venting the Primary below. \\
@@ Line 29: / Line 34: @@
-|  The transfer below valve below was packed with JB Weld to negate it's operation. ((photos by Jtrapass of the XLFORUM http://xlforum.net/forums/showthread.php?p=1095756#post1095756))  ||
+|  The transfer below valve below was packed with JB Weld to negate it's operation. ((photos by Jtrapass of the XLFORUM http://xlforum.net/forums/showthread.php?p=1095756#post1095756))  ||  Transfer valve removed, plug installed. ((photo by lofimofo of the XLFORUM http://xlforum.net/forums/showthread.php?t=1578633))  |
-|{{:techtalk:ih:oil:plugging_the_transfer_valve_1_by_jtrapass.jpg?direct&300|}}| {{:techtalk:ih:oil:plugging_the_transfer_valve_2_by_jtrapass.jpg?direct&300|}}|
+|{{:techtalk:ih:oil:plugging_the_transfer_valve_1_by_jtrapass.jpg?direct&300|}}| {{:techtalk:ih:oil:plugging_the_transfer_valve_2_by_jtrapass.jpg?direct&300|}}|{{:techtalk:ih:oil:transfer_valve_hole_plugged_by_lofimofo.jpg?direct&300|}}|
 ====== Venting the Primary ======
@@ Line 36: / Line 41: @@
 With the transfer valve plugged, the primary can't breath as it can with the transfer valve functioning. \\
 That air path would now be blocked. \\
-Technically, the primary has a vent other than the transfer valve being the clearance in the clutch cable where it enters the primary. \\
+Technically, the primary may have a vent other than the transfer valve being the clearance in the clutch cable where it enters the primary. \\
 That can also act as a vent as air can enter and escape there (the part where the actual cable goes into the threaded piece that screws into the clutch cable hole). ((Buck101 of the XLFORUM http://xlforum.net/forums/showthread.php?t=150130&page=4)) ((CrazyHorse of the XLFORUM http://xlforum.net/forums/showthread.php?t=150130&page=4)) \\
 There is slack (slop) where the cable end is pressure fitted ( by slack adjustment of cable) into the threaded piece. \\
@@ Line 44: / Line 49: @@
 **Installing a dedicated primary vent**: \\
-  * You can drill a tiny hole in the primary access plug. \\
+  * **You'd think you could use the hole in the primary access plug as a vent**.
-  * You can install a vent plug (like the 34744-77 tranny vent) through one of the holes on top of the cases, just in front of the rear engine mount bracket. \\ Those two bolt holes are used for the oil tank bracket (xlch model) or battery carrier bracket (xlh model). ((JBM of the XLFORUM http://xlforum.net/forums/showthread.php?t=146064)) \\ '77-up ironheads have this 3/4"x16 vent fitting factory installed in this location (transfer valve deleted in '77) \\ Short frame cases use 4 bolts and 3 studs to hold the rear mount to the cases. ((Dr Dick of the XLFORUM http://xlforum.net/forums/showthread.php?t=776527&page=4)) Long frame cases use 2 bolts and 3 studs. \\ On long frame cases the front two bolts were dropped to make room for the electric leg. \\ The XLH battery box / oil bracket was bolted in the vacated area. This is where the vent bolt for 77> was positioned. \\ These bracket bolts are in a position where trans oil don't seem to get tossed as much. So they don't eject much oil. \\ All 76< long frame cases (except 71XLCH) will accept the vent bolt in the 77> position. Bolt goes in the hole closest to the case parting seam. \\ Conversely, installing the vent bolt in any of the four short frame rear mount bolt holes usually results in drips from the vent.
+    * However, any non-tin cover bike with a blocked transfer will piss out the vent of the primary filler plug. ((Dr Dick of the XLFORUM http://xlforum.net/forums/showthread.php?t=776527&page=3)) \\ It's usually futile to retain the plug vent due to oil weep. Plugging that vent and installing a vent some where else is a good route.
-  * On <69 engines, you can drill and tap a hole at the top of the case on the primary side and tee into the vent line going to the oil tank. ((simeli of the XLFORUM http://xlforum.net/forums/showthread.php?t=776527&page=4))
+    * The primary filler plug part numbers are (34742-52A) for 54-70 and (34742-71) for 71 to 76. (Fridge of the XLFORUM http://xlforum.net/forums/showthread.php?t=776527&page=3))
+  * **You can use the 77-80 venting location on 70-76 engines**:
+    * You can install a vent plug (like the 34744-77 tranny vent) through one of the holes on top of the cases, just in front of the rear engine mount bracket.
+    * Those two bolt holes are used for the oil tank bracket (xlch model) or battery carrier bracket (xlh model). ((JBM of the XLFORUM http://xlforum.net/forums/showthread.php?t=146064)) \\ '77-up ironheads have this 3/4"x16 vent fitting factory installed in this location (transfer valve deleted in '77).
+    * Short frame cases use 4 bolts and 3 studs to hold rear mount to cases.
+    * Long frame cases use 2 bolts and 3 studs. ((Dr Dick of the XLFORUM http://xlforum.net/forums/showthread.php?t=776527&page=4)) \\ On long frame cases, the front two bolts were dropped to make room for the electric leg. The XLH battery box / oil bracket was bolted in the vacated area. This is where the vent bolt for 77> was positioned. \\ These bracket bolts are in a position where transmission oil don't seem to get tossed around as much. So they don't eject much oil. \\ All 76-earlier long frame cases (except 71ch) will accept the '77 vent bolt in it's intended location above the tranny.
+    * The bolt goes in the hole closest to case parting seam. \\ Conversely, installing the vent bolt in any of the four short frame rear mount bolt holes usually results in drips from the vent.
+    * However, if you use a longer hose, loop it up around the seat post and back down (as 2003-earlier Evos did), it shouldn't drip any oil. ((Hippysmack)) \\ (unless the sprocket shaft seal has blown)
+  * **You can tap a vent above the primary on 57-69 engines**:
+    * You can drill and tap a hole at the top of the case on the primary side and tee into the vent line going to the oil tank. ((simeli of the XLFORUM http://xlforum.net/forums/showthread.php?t=776527&page=4))
@@ Line 54: / Line 68: @@
 {{:techtalk:ih:oil:installing_a_transmission_vent_1_by_jtrapass.jpg?direct&300|}} ((photo by Jtrapass of the XLFORUM http://xlforum.net/forums/showthread.php?p=1082313#post1082313)) {{:techtalk:ih:oil:installing_a_transmission_vent_2_by_jtrapass.jpg?direct&300|}} ((photo by Jtrapass of the XLFORUM http://xlforum.net/forums/showthread.php?p=1082313#post1082313)) \\
+-1980 models use a fitting (34744-77) with a SAE 3/8" x 16 (x app. 7/16") bolt pattern that has a 1/4" hose nipple on the other end. \\
+{{:techtalk:ih:oil:1977_tranny_vent_pic3_by_on_.....jpg?direct&300|}} ((photo by on½.... of the XLFORUM http://xlforum.net/forums/showthread.php?p=5541672&highlight=transmission+vent#post5541672)) {{:techtalk:ih:oil:1977-1978_transmission_vent_by_hopper.jpg?direct&300|}} ((photo by Hopper of the XLFORUM http://xlforum.net/forums/showthread.php?t=209347&page=11)) \\
 \\

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