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I decided to tear down my JG pump to see for sure what impeller it has in it. It appears to have the exit edge of the vanes cut back. Are the vanes normally all the way out to the large od of the impeller, or are they back cut some.

My impeller is 9" large OD and 7.210 small od with a 7.197 wear ring surface od. That means it is an "A"? And with the vanes back cut it would be an A/B ? Vanes are back cut .270 from the large od of the impeller

Also there is no seal in the bowl in front of the shaft bushing bore. Do some shops assemble these with out the seal and use water as the lube? Or should it have the seal installed and run oil in the bowl bushing cavity.

Thanks for any help.
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the impellor appears to be a berkeley style to me, only an educated quess . the wear ring has been turned down by your measurements .028 undersize if my mathe is correct. the standard chart that i use has the large diameter at 9. inches and the smaller trailing exit at7.250 for a stock A, with a 30 degree tilt on the blades. when i cut them to a B i go to 8.750 - 6.750 with a 33 1/2 degree tilt on the blades sinking the exit of the blade evenly recessed inside the larger dimensions. there are many ways to cut them as your appears somewhat different. i have seen them cut straight across each to their own if it works. some/many use water lube i.e no seal in the bowl dominator was for years made this way. i feel that it is best that you NEVER start the pump out of the water if it is water lubed, most mfg of the pump now use some type of oil or grease system in their bowls. i personally prefer to lube them oil or grease my .02
 
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