v8250
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Over w/e cleaned and inspected the original brake vacuum pump. It's in good condition, no axial or lateral play but is scored throughout inner body wall and underside of top cover. So understanding this is a vacuum pump ordered a new unit from Bearmach which has arrived today...but, upon inspection there's 0.54mm lateral play/thrust on the shaft [top to bottom within pump housing].
Logically, as it's a 'dry' vacuum pump there must be some lateral play to ensure no rubbing/friction/wear between internal rotor and the top cover underside, nor with the rotor body to inner wall as it's the fly blades sliding outbound movement [centrifugal expansion] causing the vacuum between their profiled working edge and the inner body wall.
From your experience is 0.54mm normal play seen with new vacuum pumps?
Logically, as it's a 'dry' vacuum pump there must be some lateral play to ensure no rubbing/friction/wear between internal rotor and the top cover underside, nor with the rotor body to inner wall as it's the fly blades sliding outbound movement [centrifugal expansion] causing the vacuum between their profiled working edge and the inner body wall.
From your experience is 0.54mm normal play seen with new vacuum pumps?
