Differences
This shows you the differences between two versions of the page.
Both sides previous revision Previous revision | Next revision Both sides next revision | ||
techtalk:ref:oil15 [2019/06/13 02:12] hippysmack [Rocker Box] |
techtalk:ref:oil15 [2019/06/13 02:13] hippysmack [Testing per the FSMs] |
||
---|---|---|---|
Line 48: | Line 48: | ||
{{:techtalk:ref:oil:installing_an_oil_gauge_8_by_hippysmack.jpg?direct&300|}} | {{:techtalk:ref:oil:installing_an_oil_gauge_8_by_hippysmack.jpg?direct&300|}} | ||
{{:techtalk:ref:oil:installing_an_oil_gauge_9_by_hippysmack.jpg?direct&300|}} \\ | {{:techtalk:ref:oil:installing_an_oil_gauge_9_by_hippysmack.jpg?direct&300|}} \\ | ||
+ | |||
+ | ==== Rocker Box ==== | ||
+ | |||
+ | A Sportster does produce oil pressure in the rocker box: reportedly 3-5 psi at hot idle and 15psi+ on cold startup on an ironhead. ((simeli of the XLFORUM http://xlforum.net/forums/showthread.php?t=263589&highlight=lower+oil+pump&page=4)) \\ | ||
+ | Depending on the gauge selected, there may be little to no oil pressure registered on a high range gauge testing form the rocker box. \\ | ||
+ | (the gauge may show some pressure when the oil is cool and thick but may not show any after 5 minutes of running) ((mycle1000 of the XLFORUM http://xlforum.net/forums/showthread.php?t=263589&highlight=lower+oil+pump&page=3)) \\ | ||
+ | Due to the low oil pressure at the rocker box, \\ | ||
+ | Don't get scared when you look down after its hot and its on zero. ((vyper202 of the XLFORUM http://xlforum.net/forums/showthread.php?t=1698960)) \\ | ||
+ | |||
+ | * Residual crankcase pressure and working pressure from the lifters resides in the rocker boxes. | ||
+ | * On a cold startup, the pressure is higher due to the thicker oil present. | ||
+ | * As the engine warms up, the oil thins out and the pressure is reduced in the rocker boxes. | ||
+ | * Excess crankcase pressure (air and oil mist) is vented differently between pre and post 91 engines. | ||
+ | * On pre 91 engines, excess crankcase pressure is vented through the cam cover. | ||
+ | * On post 91 engines, excess crankcase pressure is routed up the pushrod tubes and vented thru the rocker boxes to exit a hole in each head. | ||
+ | * So, it is possible to notice different pressures from them with a pressure gauge testing from the rocker box. | ||
+ | * However, a gauge tapped into any rocker box will most likely measure air pressure instead of oil pressure. | ||
+ | * As air will compress and oil will not, therefore the readings should be lower than if you were testing at the oil pressure switch. | ||
===== 86 and Up models ===== | ===== 86 and Up models ===== |