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--- techtalk:evo:engmech04c [2019/01/06 20:59]
hippysmack created
+++ techtalk:evo:engmech04c [2021/11/12 22:42]
hippysmack [Bolt Installation Sequence]
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-====== EVO: Engine Mechanicals - Sub-04A ======
+====== EVO: Engine Mechanicals - Sub-04C ======
 ====== Installing the Rocker Boxes ======
-See also [[techtalk:evo:engmech04b#rocker_box_rocker_arm_inspection_and_repair|Rocker Box / Rocker Arm Inspection and Repair]] in the Sportsterpedia. \\
+See also in the Sportsterpedia;
+  * [[techtalk:evo:engmech04a#removing_the_rocker_boxes|Removing the Rocker Boxes]] \\
+  * [[techtalk:evo:engmech04b#rocker_box_rocker_arm_inspection_and_servicing|Rocker Box / Rocker Arm Inspection and Servicing]]
+\\
+One issue in installing the rocker box is that it has no alignment method. ((aswracing of the XLFORUM http://xlforum.net/forums/showthread.php?t=1933342&page=13)) \\
+Basically, every time you put it on, it's in a different place. \\
+When installing the rocker boxes, be sure to put them on with the engine positioned such that the cams aren't trying to open the valves. ((aswracing of the XLFORUM http://xlforum.net/forums/showthread.php?t=322680&page=3)) \\
+Else you can damage parts. \\
+===== Compatibility =====
+Middle rocker box: \\
+The 86-90 doesn't incorporate the area were the umbrella flapper valve would go. ((dave76 of the XLFORUM http://xlforum.net/forums/showthread.php?t=732143)) \\
+So due to functionality, the 86-90 mid section won't fit 91-03 boxes. \\
+But the 91-03 middle cover will fit 86-90 boxes. \\
+===== Gaskets =====
+Clean the mating surfaces of all oil / trash before setting the gaskets in place. \\
+With the bolts 'lightly' hand seated, check all around the box for a gasket squirting out the side before tightening the bolts. \\
+It's easy to 'just nudge' the top section and squeeze a portion of the rubber gasket out while positioning it. \\
+See [[http://sportsterpedia.com/lib/exe/fetch.php/pdf-bulletin:tt0253.pdf|TT#253]] regarding the top rocker box gasket.
+{{:techtalk:evo:engmech:pinched_rocker_box_gasket_1_by_sep69.jpg?direct&300|}} ((photo by sep69 of the XLFORUM http://xlforum.net/forums/showthread.php?p=3754227)) {{:techtalk:evo:engmech:pinched_rocker_box_gasket_2_by_sep69.jpg?direct&300|}} ((photo by sep69 of the XLFORUM http://xlforum.net/forums/showthread.php?p=3754227)) \\
+===== Bolt Installation Sequence =====
+The FSM details the proper installation sequence of the bolts. \\
+Installing the bolts in the proper order prevents potentially warpage of the cover(s). \\
+It also mentions making sure that both valves are closed prior to removal. \\
+On assembly, it's even more important to slowly tighten things in the proper order to allow the lifters to bleed down. \\
+(prevents things like bent push rods and destroying the cam bushings). \\
+Also, make sure you can spin the push rods BEFORE turning the motor over the first time. \\
+Obviously, you can skip these steps and get lucky. \\
+But, why? Just follow the manual, it's easy enough to do correctly. \\
+Below are pictures of the lower rocker box. \\
+The circled areas are where the bolts would be: \\
+ **On assembly**: ((Screw Loose Dan of the XLFORUM http://xlforum.net/forums/showthread.php?s=c412e43a4339648eaaa7872371a84820&p=4008995)) \\
+  * Work in this order. Blue->red->yellow. \\ It is suggested to do this slowly (one turn at a time) and for the blue ones to do it in a cross pattern. \\ This is to bleed the lifters properly.
+  * An easy way to remember the order is to work from the larger bolts to the smaller ones.
+  * If you start with the red ones, you can easily strip the threads in the heads.
+**Torque values**: \\
+Installing the bolts in the correct order doesn't take much longer and saves some potential headaches. \\
+While many experienced guys won't use a torque wrench on the smaller fasteners, it is suggested to use one. \\
+It doesn't take much to strip one of these for new or experienced mechanics. \\
+    * Blue - 18-22 ft-lbs
+    * Red - 135-155 in-lbs
+    * Yellow - 135-155 in-lbs
+|91-03 style lower rocker box ((photo by Hippysmack))|04 and up style lower rocker box ((photo by Screw Loose Dan of the XLFORUM http://xlforum.net/forums/showthread.php?s=c412e43a4339648eaaa7872371a84820&p=4008995))|
+|{{:techtalk:evo:oil:91-03_lower_rocker_box_by_hippysmack.jpg?direct&300|}}|{{:techtalk:evo:engmech:rocker_box_screw_locations_by_screw_loose_dan.jpg?direct&300|}}|
+===== Check Pushrod Length =====
+A hydraulic lifter has a plunger in it's body that has about .200" of movement. ((http://www.hammerperf.com/ttpushrodlength.shtml)) Oil sits under the plunger and pushes it up to take the slack out of the valve train. \\
+In the ideal world, the plunger is approximately centered in it's travel, meaning it's preloaded about .100". \\
+So in theory,\\
+It could move up, thus lengthening the effective length of the lifter to compensate for a pushrod that's up to .100" too short. \\
+And likewise, it could move down, thus shortening the effective length of the lifter to compensate for a pushrod that's up to .100" too long. \\
+This self adjusting action is also useful for compensating for changes in needed pushrod length due to engine temp variations. \\
+As the motor heats up, the top end grows and the lifter automatically takes up the slack. \\
+In reality, \\
+The useful operating range of the lifter plunger is only about .050" in either direction away from centered (.050" to .150" of preload). \\
+Outside of this range, the self adjusting function doesn't work nearly as well.
+You can measure lifter pre-load to determine if the pushrods are in the size range needed. This method will get you close. ((http://www.hammerperf.com/ttpushrodlength.shtml)) \\
+The cam lobes should be down (as they should be when installing a rocker box). \\
+Set the pushrods in place (the longer one goes on the exhaust) and then place the gasket and rocker box on top installing the four big screws only. \\
+Finger tighten the left (spark plug) side, while making sure the right side is resting with the upper pushrod ends sitting in the cups on the rocker arms. \\
+Use a caliper to measure how much gap you have between the rocker box and the rocker box gasket. \\
+The lifter preload should be app. .100" but anywhere between .050" and .150" should work. \\
+Aftermarket pushrods can be purchased in longer or shorter lengths than stock ones to get the measurement within .100".
+{{:techtalk:evo:engmech:lifter_preload_by_aswracing.jpg?direct&200|}} ((photo by aswracing of the XLFORUM http://xlforum.net/forums/showthread.php?t=322680&page=5)) \\
 \\