Differences

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--- techtalk:ref:genmsr04 [2020/10/25 23:20]
hippysmack [Testing crankcase pressure]
+++ techtalk:ref:genmsr04 [2023/12/26 22:52] (current)
hippysmack
@@ Line 1: / Line 1: @@
 [[:techtalk:menu|{{  :techtalk:gototechnicalmenu.jpg|}}]]
-====== REF: Engine Mechanicals - Sub-04F ======
+====== REF: General-MSR 04 ======
 \\
 ====== Using / Diagnosing with a Slack Tube (Manometer) ======
 See also in the Sportsterpedia: \\
   * [[techtalk:ref:tools173#manometer_slack_tube_for_measuring_air_pressure|Manometer (slack tube) for Measuring Air Pressure]] (what it is and how it works)
   * [[techtalk:ref:engmech04e|Building Your Own Slack Tube]]
+  * [[techtalk:ref:genmsr04a|Modifying a Rubber Stopper for Oil Tank Pressure Testing]]
   * [[techtalk:ref:engmech04g|Slack Tube Testing on a 1998 1250S Sportster]]
+  * [[techtalk:ref:engmech07p|Testing with a Slack Tube (Manometer) by bustert]]
 Pressure measurements given in inches or millimeters of water / mercury / other liquid are based on the earliest instrument developed for measuring pressure, the liquid column gauge or manometer (AKA slack tube). ((https://www.industrialspec.com/about-us/blog/detail/vacuum-unit-conversion-chart-ism-technical-resource)) \\
@@ Line 16: / Line 17: @@
 |{{:techtalk:ref:genmsr:86-up_manometer_connection_points_by_hippysmack.png?direct&400|}}|
-==== Timing Hole Plug (57-03) ====
+==== Valve vs No Valve on Source Outlet ====
+A valve is sometimes used on the source outlet to connect the test line to the manometer. \\
+This is a safety precaution in case more vacuum is being pulled than the manometer is calibrated for. \\
+Example, the water level in the right leg of a U-tube manometer cannot be allowed to go down past the "U" in the bottom of the tool. \\
+If this happens, all of the water will be sucked inside the engine from there. \\
+If you have a 3 foot tall manometer and are only measuring 1 PSI or less air pressure, no valve will be needed. \\
+However, if the source is pulling 1-1/2" or more of vacuum, the water will be sucked into the engine unless the manometer is taller. \\
+A taller height of water column increases the air pressure it can measure. \\
+See the chart below for pressure conversions. \\
+If you are unsure about the amount of vacuum the engine is running, it may be best to buy a gauge that measures in In Hg or use a taller manometer. \\
+Or, you can install a valve on the source outlet to throttle (control) the air pressure that goes to the manometer. \\
+The ID of the valve needs to be no less than the ID of the source outlet (1/4" outlet needs a 1/4" or higher ID valve). \\
+You can pinch off the clear hose with your fingers, start the engine and gradually let go of the hose to see if the water is going to back feed into the engine. \\
+That way you'll know for sure if you need a valve or not. \\
+==== Timing Hole Plug (57-03) ====
   * This method won't work on 04-up models as they have no timing hole plug. \\ Basically you need some clear vinyl hose and a nipple fitting to replace the timing hole plug.
     * 1957-2003 engines have a timing plug hole that can be removed and a couple fittings with a hose barb end can be installed to accept the hose.
@@ Line 23: / Line 39: @@
 |  **Timing hole plug fittings**  |||
-|3/8" flare to 1/4" FPT fitting \\ with a 1/4" MPT to 3/8" hose barb. ((photo by aswracing of the XLFORUM http://xlforum.net/forums/showthread.php?t=1946516&page=4))|3/8" NPT x 1/4" NPT bushing and a 1/4" NPT to 1/8" hose barb fiting. ((photos by Hippysmack of the XLFORUM http://xlforum.net/forums/showthread.php?p=5784790#post5784790))||
+|3/8" flare to 1/4" FPT fitting \\ with a 1/4" MPT to 3/8" hose barb. ((photo by aswracing 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/180842-crankcase-vent-question/page4?t=1946516&page=4))|3/8" NPT x 1/4" NPT bushing and a 1/4" NPT to 3/16" hose barb fiting. ((photos by Hippysmack 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/page52#post4349847))||
-|{{:techtalk:ref:engmech:timing_plug_adapter_by_aswracing.jpg?direct&300|}}|{{:techtalk:ref:genmsr:timing_hole_fitting_for_slack_tube.jpg?direct&300|}}| {{:techtalk:ref:engmech:homemade_slack_tube_1_by_hippysmack.jpg?direct&300|}}|
+|{{:techtalk:ref:engmech:timing_plug_adapter_by_aswracing.jpg?direct&300|}}|{{:techtalk:ref:genmsr:timing_hole_fitting_for_slack_tube_by_hippysmack.jpg?direct&300|}}| {{:techtalk:ref:engmech:homemade_slack_tube_1_by_hippysmack.jpg?direct&300|}}|
-|  Fitting installed (just snugged up) with clear hose and a homemade manometer. ((photos by Hippysmack of the XLFORUM http://xlforum.net/forums/showthread.php?p=5784790#post5784790))  |||
+|  Fitting installed (just snugged up) with clear hose and a homemade manometer. ((photos by Hippysmack 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/page52#post4349847))  |||
 |{{:techtalk:ref:engmech:homemade_slack_tube_7_by_hippysmack.jpg?direct&300|}}|{{:techtalk:ref:engmech:homemade_slack_tube_8_by_hippysmack.jpg?direct&300|}}| {{:techtalk:ref:engmech:homemade_slack_tube_5_by_hippysmack.jpg?direct&300|}}|
-==== Oil Tank Vent Line ====
+==== Oil Tank / Vent Line ====
 **You can test crankcase pressure from the tank vent** as it will show the amount of vacuum that is being created between the cam chest and the oil tank. \\
 This measurement (when tested on a 2001 XL1200S) was lower than when the same engine was tested from the crankcase. \\
@@ Line 44: / Line 59: @@
 **Make sure the test hose stays above the tee / fitting at all times** to keep oil from dripping / draining into the test hose. \\
-|Slack Tube testing from timing hole plug. ((photos by bustert of the XLFORUM http://xlforum.net/forums/showthread.php?p=5767694#post5767694))||Slack Tube testing from oil tank||
+The results below are in (inches of water) but remember, you have to add both sides. \\
+So a 15" rise on one side with a 15" decrease on the other would be 30" of water column total. \\
+These tests were done from both the crankcase and the oil tank. \\
+The crankcase was tested from the timing plug and the oil tank was tested with a modded spare oil cap. \\
+So the pics on the right represent actual working pressure in the tank. \\
+|Slack Tube testing from timing hole plug. ((photos by bustert 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/page31#post4326111))||Slack Tube testing from oil tank||
 |1000 \\ RPM|{{:techtalk:ref:engmech:checking_cc_pressure_at_timing_hole_plug_1_by_bustert.jpg?direct&300|}}|{{:techtalk:ref:engmech:checking_cc_pressure_at_oil_tank_1.1_by_bustert.jpg?direct&300|}}|1000 \\ RPM|
 |6000 \\ RPM|{{:techtalk:ref:engmech:checking_cc_pressure_at_timing_hole_plug_6_by_bustert.jpg?direct&300|}}|{{:techtalk:ref:engmech:checking_cc_pressure_at_oil_tank_6_by_bustert.jpg?direct&300|}}|6000 \\ RPM|
+==== Modified Oil Tank Cap ====
+You can drill a hole for an NPT fitting in a spare oil cap or make a cap just for testing. \\
+The one below was made from a rubber plug bought at Lowes. [[techtalk:ref:genmsr04a|Click here]] to see the pics of the mod. \\
+{{:techtalk:ref:genmsr:homemade_test_oil_cap_6_by_hippysmack.jpg?direct&300|}} ((photo by Hippysmack)) \\
+If you're testing the 04-up plastic oil tank for high pressure, the oil cap is not going to be helpful as a test point. \\
+You need a tee installed in the vent line for that. \\
 ====== Testing crankcase pressure ======
@@ Line 58: / Line 88: @@
     * Convert metric measurements to inches if needed.
     * The result is expressed as the pressure in Inches of Water Column.
 At idle gives the most vacuum in the crankcase you'll have throughout the RPM range. \\
@@ Line 81: / Line 109: @@
 ====== Conversion Chart ======
 Conversion Results Rounded: \\
 Click here {{:techtalk:ref:engmech:pressure_conversion_chart_by_hippysmack.png?direct&50}} to open a picture of the chart. ((drawing by Hippysmack)) \\
@@ Line 94: / Line 121: @@
 |6|.441|14.95|.217^ |13|.956|32.38|.470^ |20|1.471|49.82|.713^ |27|1.986|67.25|.975^ |34|2.501|84.69|1.228|
 |7|.515|17.44|.253^ |14|1.03|34.87|.506^ |21|1.545|52.31|.759^ |28|2.060|69.74|1.012^ |35|2.574|87.18|1.264|
 ====== Calculating Between PSI and Inches of Water ======
 The standard conversion from PSI to Inches of Water: 1 PSI is equal to 28" of water column (overall vertical movement). \\
 When using a U-tube type manometer, divide the total inches of water travel (in both legs) by 2 as the water in each leg of the instrument are moving. \\
@@ Line 116: / Line 140: @@
 ====== Inches of Water to Inches of Mercury (Hg) ======
 " of water column = 0.073555905223332" in Hg.
 ====== Calculating Pascal Units ======
@@ Line 190: / Line 213: @@
 Zero Absolute Pressure. \\
 The complete absence of any gas; a perfect vacuum.
 \\

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