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JFP in PA · 05-31-2019, 01:05 PM

All the AOS operate the same way, they are a throttling device, not unlike the cooling system's thermostat, the take a relatively high vacuum level at the intake (well over 20 inches of mercury) and reduce it to a level (five inches of water) conducive to controlling the low tension rings pressure against the cylinder liners. Regardless of how high or low the intake vacuum level is, the AOS will hold that steady five inches of water in the sump. As a comparison, you cannot even see 5 inches of water on a vacuum gauge calibrated to inches of mercury. One inch of water is only 0.0734824 inches of mercury, so five inches of water is only 0.367 inches of mercury, not enough to even move the needle on a tool calibrated in inches or mercury, hence the need for manometer to read the lower vacuum levels accurately.

05-31-2019, 01:05 PM	#47
JFP in PA Registered User Join Date: Feb 2005 Location: It's a kind of magic..... Posts: 6,273	All the AOS operate the same way, they are a throttling device, not unlike the cooling system's thermostat, the take a relatively high vacuum level at the intake (well over 20 inches of mercury) and reduce it to a level (five inches of water) conducive to controlling the low tension rings pressure against the cylinder liners. Regardless of how high or low the intake vacuum level is, the AOS will hold that steady five inches of water in the sump. As a comparison, you cannot even see 5 inches of water on a vacuum gauge calibrated to inches of mercury. One inch of water is only 0.0734824 inches of mercury, so five inches of water is only 0.367 inches of mercury, not enough to even move the needle on a tool calibrated in inches or mercury, hence the need for manometer to read the lower vacuum levels accurately. __________________ “Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein Last edited by JFP in PA; 05-31-2019 at 01:17 PM.