Differences

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--- techtalk:ref:svcproc23 [2018/10/23 02:40]
hippysmack [Duration]
+++ techtalk:ref:svcproc23 [2019/05/31 00:10]
hippysmack [Why Degree Your Cams?]
@@ Line 1: / Line 1: @@
 [[:techtalk:menu|{{  :techtalk:gototechnicalmenu.jpg|}}]]
-====== REF: Troubleshooting - 06 ======
+====== REF: Service Procedures 23 ======
 ====== Degree-ing Cams ======
@@ Line 22: / Line 22: @@
   * You can also degree the cams to eliminate errors in;
     * General manufacturing of the cams.
-    * Proper cam installation.
+    * Proper cam installation. \\ A compression test will also immediately point out a cam timing problem. ((aswracing of the XLFORUM http://xlforum.net/forums/showthread.php?p=2670787&highlight=degree#post2670787)) \\ See also [[techtalk:ref:svcproc20#cylinder_compression_test|Performing a cylinder compression test]] in the REF section of the Sportsterpedia.
 ====== Setting up the Equipment ======
-  * You'll need to [[techtalk:ref:trouble05#finding_tdc_of_the_piston|Find True TDC of the Piston]] for precise measurements.
+{{:techtalk:ref:tools:degreeing_cams_by_povertyflats.jpg?direct&400|}} ((photo by povertyflats of the XLFORUM http://xlforum.net/forums/showthread.php?s=03729fd1877416d73eb9535bdf896822&p=5503895))
-    * See also [[techtalk:ref:trouble05#find_true_tdc_using_a_piston_stop_and_a_degree_wheel|Finding True TDC Using a Piston Stop and a Degree Wheel]]
+  * You'll need to [[techtalk:ref:svcproc22#finding_tdc_of_the_piston|Find True TDC of the Piston]] for precise measurements.
+    * See also [[techtalk:ref:svcproc22#find_true_tdc_using_a_piston_stop_and_a_degree_wheel|Finding True TDC Using a Piston Stop and a Degree Wheel]]
   * Or, for spot checking cam installation, a dial caliper placed in the spark plug hole and a degree wheel will do to find TDC.
-    * See also [[techtalk:ref:trouble05#find_true_tdc_using_a_dial_indicator_and_a_degree_wheel|Finding True TDC Using a Dial Indicator and a Degree Wheel]]
+    * See also [[techtalk:ref:svcproc22#find_true_tdc_using_a_dial_indicator_and_a_degree_wheel|Finding True TDC Using a Dial Indicator and a Degree Wheel]]
     * By using only a dial indicator on top of the piston, the point where the indicator falls off it's high point will be different. \\ (depending on which direction you rotate the engine to find the high point). ((rivethog of the XLFORUM http://xlforum.net/forums/showthread.php?t=1507847))
     * There will be a few degrees of interpretation before the piston rolls back down.
     * However, a cam gear off by a tooth will show much more of a degree change than the caliper dwell at TDC.
-  * See also [[techtalk:ref:trouble05#confirming_which_tdc_you_re_on_using_the_timing_rotor_cup|Confirming Which TDC You're On Using the Timing Rotor Cup]] in the Sportsterpedia for pics showing the different cam gear positions at TDC (compression) and TDC (exhaust) strokes for each cylinder.
+  * See also [[techtalk:ref:svcproc22#confirming_which_tdc_you_re_on_using_the_timing_rotor_cup|Confirming Which TDC You're On Using the Timing Rotor Cup]] in the Sportsterpedia for pics showing the different cam gear positions at TDC (compression) and TDC (exhaust) strokes for each cylinder.
 |Oil the lifter bodies to ensure smooth up and down \\ movement.|Install a dial indicator over the top of the lifter being \\ tested. It doesn't have to be zero'd yet, but lower it \\ enough so the probe will still touch the lifter the \\ when it is all the way down.|Install a piston stop or dial indicator in the spark \\ plug hole for locating TDC (front head for cams 3-4 \\ & rear head for cams 1-2). See the links above for \\ finding TDC.|
-|{{:techtalk:ref:trouble:degreeing_cams_1_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:trouble:degreeing_cams_2_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:trouble:degreeing_cams_3_by_hippysmack.jpg?direct&300|}}|
+|{{techtalk:ref:svcproc:degreeing_cams_1_by_hippysmack.jpg?direct&300|}}|{{techtalk:ref:svcproc:degreeing_cams_2_by_hippysmack.jpg?direct&300|}}|{{techtalk:ref:svcproc:degreeing_cams_3_by_hippysmack.jpg?direct&300|}}|
 |Once you've found piston TDC, remove the piston stop or dial indicator from the spark plug hole. \\ Install a degree wheel on either the crankshaft or pinion shaft (without moving the piston location).|||
-|{{:techtalk:ref:trouble:degreeing_cams_4_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:trouble:degreeing_cams_5_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:trouble:degreeing_cams_6_by_hippysmack.jpg?direct&300|}}|
+|{{techtalk:ref:svcproc:degreeing_cams_4_by_hippysmack.jpg?direct&300|}}|{{techtalk:ref:svcproc:degreeing_cams_5_by_hippysmack.jpg?direct&300|}}|{{techtalk:ref:svcproc:degreeing_cams_6_by_hippysmack.jpg?direct&300|}}|
 |Install a pointer on the engine (a cut up close hanger works well). \\ It should come over the wheel and point directly at the center and parallel with the hash marks without touching the wheel.|||
-|{{:techtalk:ref:trouble:degreeing_cams_7_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:trouble:degreeing_cams_8_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:trouble:degreeing_cams_9_by_hippysmack.jpg?direct&300|}}|
+|{{techtalk:ref:svcproc:degreeing_cams_7_by_hippysmack.jpg?direct&300|}}|{{techtalk:ref:svcproc:degreeing_cams_8_by_hippysmack.jpg?direct&300|}}|{{techtalk:ref:svcproc:degreeing_cams_9_by_hippysmack.jpg?direct&300|}}|
 |You may have to adjust both the pointer and the wheel for alignment. Be sure the piston is still at TDC before making final adjustments. \\ With the wheel zero'd at TDC, spin the engine over and watch for movement of the lifter being tested. \\ When the cam is on the base circle, the dial indicator shouldn't move. \\ Move the indicator face to zero and rotate the engine several degrees to insure the lifter is settled in that position. \\ Adjust the dial face as necessary to ensure it stays on zero when it should.|||
-|{{:techtalk:ref:trouble:degreeing_cams_10_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:trouble:degreeing_cams_11_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:trouble:degreeing_cams_12_by_hippysmack.jpg?direct&300|}}|
+|{{techtalk:ref:svcproc:degreeing_cams_10_by_hippysmack.jpg?direct&300|}}|{{techtalk:ref:svcproc:degreeing_cams_11_by_hippysmack.jpg?direct&300|}}|{{techtalk:ref:svcproc:degreeing_cams_12_by_hippysmack.jpg?direct&300|}}|
-The equipment is now set up for testing.
+**Note**: \\
+  - It is advisable to rotate the engine over several TDCs and ensure the dial indicator returns to zero after rising and falling. \\ Stop at certain degrees along the way, note the readings on the indicator and repeat.
+  - If the indicator fails to stop on the same the spot repeatedly, your test results will vary. \\ Reposition the indicator, zero the face and repeat note 1 above.
+  - When you have confirmed accurate placement of the indicator, the equipment is now set up for testing.
 ===== Equipment Specifics =====
@@ Line 95: / Line 101: @@
 The duration can be calculated from the published timing figures. \\
-===== Cam Lift =====
+===== Cam Lobe Lift =====
 The actual cam lift is any amount of lift greater (taller) than the base circle. \\
 This corresponds to how far the valves are open. \\
@@ Line 114: / Line 120: @@
 Check all four cams and compare the results. \\
+You can also measure cam lobe lift with the cams removed by using a caliper. ((rocketmangb of the XLFORUM http://xlforum.net/forums/showthread.php?s=73d24db8f0756ef41c6215fd92ad0055&p=4726240)) \\
+The base circle is the smallest dimension of a cam lobe. \\
+If you measure the largest dimension of the lobe and subtract the smallest dimension you get the lobe lift. \\
+Multiply that by the rocker ratio and you get the valve lift. \\
@@ Line 132: / Line 143: @@
 |  **Intake Stroke**  |||  **Exhaust Stroke**  |||
 |Valve opening, \\ Cam lift is .053"|Intake Stroke Length|Valve Closing, \\ Cam lift is .053"|Valve opening, \\ Cam lift is .053"|Exhaust Stroke Length|Valve Closing, \\ Cam lift is .053"|
-|  30° before \\ TDC compression \\ or (BTDC)  |  180°  |  46° after \\ BDC \\ or (ABDC)  |  52°  |  180°  |  24°  |
+|  30° before \\ TDC Exhaust \\ or (BTDC)  |  180°  |  46° after \\ BDC \\ or (ABDC)  |  52°  |  180°  |  24°  |
 |  Calculated Intake Cam Duration: 30+180+46 = 256°  |||  Calculated Exhaust Cam Duration: 52+180+24 = 256°  |||
@@ Line 142: / Line 153: @@
     - Calculate the length, in degrees, between the two numbers to get the duration advertised.
-**Example** using Andrews N4s on #2 Intake Cam:
+**Example** using Andrews N4s on the rear intake cam:
 |  1. Cam on the base circle, degree wheel zero'd at TDC  ((photos by Hippysmack))  ||
-|{{:techtalk:ref:trouble:degreeing_cams-duration_i1_by_hippysmack.jpg?direct&400|}}|{{:techtalk:ref:trouble:degreeing_cams-duration_i2_by_hippysmack.jpg?direct&400|}}|
+|{{techtalk:ref:svcproc:degreeing_cams-duration_i1_by_hippysmack.jpg?direct&400|}}|{{techtalk:ref:svcproc:degreeing_cams-duration_i2_by_hippysmack.jpg?direct&400|}}|
 |2. With rotated cam lobe height at .053", \\ Degree wheel shows: \\ 30° before TDC (BTDC) on exhaust stroke ((photo by Hippysmack))|3. Continued rotation up / back down to .053" cam lobe height. \\ Degree wheel shows: \\ 46° after bottom dead center (ABDC) ((photo by Hippysmack))|
-|{{:techtalk:ref:trouble:degreeing_cams-duration_i3_by_hippysmack.jpg?direct&400|}}|{{:techtalk:ref:trouble:degreeing_cams-duration_i4_by_hippysmack.jpg?direct&400|}}|
+|{{techtalk:ref:svcproc:degreeing_cams-duration_i3_by_hippysmack.jpg?direct&400|}}|{{techtalk:ref:svcproc:degreeing_cams-duration_i4_by_hippysmack.jpg?direct&400|}}|
 |4. Calculate advertised duration: \\ 30° BTDC + 180° (TDC to BDC) + 46° ABCD = 256° ((photo by Hippysmack))|
-|{{:techtalk:ref:trouble:degreeing_cams-duration_i4.01_by_hippysmack.jpg?direct&400|}}|
+|{{techtalk:ref:svcproc:degreeing_cams-duration_i4.01_by_hippysmack.jpg?direct&400|}}|
 This can also be done to measure true duration by tossing out the .053" height. \\
@@ Line 170: / Line 181: @@
 High TDC lift figures can also cause issues with valve to valve clearance.
+**Example** using Andrews N4s on the rear intake cam:
+|1. Cam on the base circle, dial indicator set at '0'. \\ Degree wheel zero'd at TDC (compression)  ((photo by Hippysmack))|2. Rotate the crankshaft forward until the pointer is at TDC on exhaust \\ stroke. Note the measurement on the dial indicator: \\ In this case it is .130" ((photos by Hippysmack))|
+|{{techtalk:ref:svcproc:degreeing_cams-duration_i2_by_hippysmack.jpg?direct&400|}}|{{techtalk:ref:svcproc:degreeing_cams-tdc_lift_2_by_hippysmack.jpg?direct&400|}}|
+  * This test repeated revealed 2° difference at the following TDC stop point.
+  * The dial indicator was repositioned and repeated results were different but consistent.
+With the dial indicator repositioned:
+|1. Cam on the base circle, dial indicator set at '0'. \\ Degree wheel still set properly.  ((photo by Hippysmack))|2. Rotate the crankshaft forward until the pointer is at TDC on exhaust \\ stroke. Note the measurement on the dial indicator: \\ Now at a repeatable result of .137" ((photos by Hippysmack))|
+|{{techtalk:ref:svcproc:degreeing_cams-tdc_lift_4_by_hippysmack.jpg?direct&400|}}|{{techtalk:ref:svcproc:degreeing_cams-tdc_lift_5_by_hippysmack.jpg?direct&400|}}|
+|3. Calculate TDC Lift: \\ .137 * 1.633 = .223721" (or .224") \\ .137 * 1.625 = .2226" (or .227")|
 ===== Wear Loss of the Cam Lobes =====
 ==== #2 Cam Gear Location ====
@@ Line 184: / Line 207: @@
  as in the pic below): \\
-|{{:techtalk:ref:trouble:2_cam_outside_gear_position_1_by_hippysmack.jpg?direct&500|}}|
+|{{techtalk:ref:svcproc:2_cam_outside_gear_position_1_by_hippysmack.jpg?direct&500|}}|
 |#2 Cam, Outside Gear Location (91 and Up Models) ((photo by Hippysmack))|

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