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techtalk:ref:engmech04r [2020/10/20 22:56] hippysmack [Measuring Engine Vacuum] |
techtalk:ref:engmech04r [2020/10/20 23:19] hippysmack [Measuring Engine Crankcase Vacuum] |
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| * 1250cc | * 1250cc | ||
| * The crankcase pressure had a mean vacuum of 21" of water column. | * The crankcase pressure had a mean vacuum of 21" of water column. | ||
| - | * At 630 feet above sea level, ambient atmosphere is applying app. 29.24" Hg of force (397.52" WC or 14.36 PSIA). | + | * At 630 feet above sea level, ambient atmosphere is applying app. 29.24" Hg of force (397.52" WC or 14.36 PSIA). \\ (both outside in and inside out of a parked engine) |
| * Vacuum at idle created by the pistons lowered ambient atmosphere inside by 21" WC. | * Vacuum at idle created by the pistons lowered ambient atmosphere inside by 21" WC. | ||
| * So the mean pressure against the gaskets and seals at 1000 RPM (breather valves closed) was 376.21" WC (27.67" Hg or 13.59 PSIA). | * So the mean pressure against the gaskets and seals at 1000 RPM (breather valves closed) was 376.21" WC (27.67" Hg or 13.59 PSIA). | ||
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| * [[techtalk:ref:engmech07p|Testing with a Slack Tube (Manometer) by bustert]], (elevation app 12.8 feet); | * [[techtalk:ref:engmech07p|Testing with a Slack Tube (Manometer) by bustert]], (elevation app 12.8 feet); | ||
| * The crankcase pressure had a mean vacuum of 30" of water column. | * The crankcase pressure had a mean vacuum of 30" of water column. | ||
| - | * At 12.8 feet above sea level, ambient atmosphere is applying app. 29.91" Hg of force (406.63" WC or 14.69 PSIA) | + | * At 12.8 feet above sea level, ambient atmosphere is applying app. 29.91" Hg of force (406.63" WC or 14.69 PSIA). \\ (both outside in and inside out of a parked engine) |
| * Vacuum at idle created by the pistons lowered ambient atmosphere inside by 30" WC. | * Vacuum at idle created by the pistons lowered ambient atmosphere inside by 30" WC. | ||
| * So the mean pressure against the gaskets and seals at 1000 RPM (breather valves closed) was 376.63" WC (27.70) Hg or 13.60 PSIA) | * So the mean pressure against the gaskets and seals at 1000 RPM (breather valves closed) was 376.63" WC (27.70) Hg or 13.60 PSIA) | ||
