1966 Chevy Caprice Breaking Water Pumps

BRUCE MCPHEE

MEMBER
1966 CHEVROLET CAPRICE

Engine Cooling problem
1966 Chevy Caprice V8 Two Wheel Drive Automatic 500-mi miles

396 rebuilt BB - - -Broke pump shaft flush with pump housing. Replaced fan, 'new' pump rad, ect. Few mi later the exact same thing again- flush with the pump, new rad ect. Both times it broke while making a quick 1.5 sec rev @ about 5-6 thous. RPM. There was no vibration or any wobble at all. Both times setting up a stupid holly.

1 Reply

HMAC300

MECHANIC
48,601 POSTS

Firstthing to do is pull the belt off and check your alignment of the pulleys. They should be aligned and not off center. Then you didn't say whether you have a fan/clutchfan or what on your car. Those may be bent especially since it happened so soon. Also check your water pump pulley for being bent. If youput the pulley on a flat surface and another straight edge on the top of the pulley measure it on both sides it should be with in.001" to.003" at the very most. If you are a machinist measure it on a surface plate with a height gage. Then before you put the new pump on measure it the same way to where the pulley mounts to make sure you aren't getting one that is screwed up.