Oil pump gear to crankshaft clearance
#1
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Hi all,
Have not come across any specification in the FSM or alternative researching, regarding the clearance between the flats of the crankshaft and oil pump gear.
Could I please request to be pointed in the right direction to obtain this information?
It appeared to me that the clearance, prior to being removed, may have been larger than the allowable limit to cause localised wear as per the images.
The crankshaft and oil pump flats measured to be 37.42mm (1.473") and 37.60mm (1.480") respectively.
Have not come across any specification in the FSM or alternative researching, regarding the clearance between the flats of the crankshaft and oil pump gear.
Could I please request to be pointed in the right direction to obtain this information?
It appeared to me that the clearance, prior to being removed, may have been larger than the allowable limit to cause localised wear as per the images.
The crankshaft and oil pump flats measured to be 37.42mm (1.473") and 37.60mm (1.480") respectively.
#3
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Yes, it is an oem bp4w pump.
Such wear does seem common amongst other used b6/bp crankshafts (google images).
I speculate that the BE gears being of greater hardness than oem could exacerbate the issue?
I have not run an indicator over the surface of the crank, but there is tangible difference under the nailmometer test...
Such wear does seem common amongst other used b6/bp crankshafts (google images).
I speculate that the BE gears being of greater hardness than oem could exacerbate the issue?
I have not run an indicator over the surface of the crank, but there is tangible difference under the nailmometer test...
#5
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Obviously not applying to any miata, but I found some clearances that you could expect to see for the same type of oil pump drive design.
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#7
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The clearance we provide on our pumps is made that way so that the gear can move around under heavy crank walk conditions. As far as I know we've never lost a pump due to actual structural failure up to 900 whp and over 10000 RPM in the BP engines. So as far as structural failure you are safe, and these wear patterns look typical for what we would see in a BP motor. Our gears are a fair bit harder then OEM, and will tend to wear the crank surface in general compared to the stock units which read below Rockwell C.
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