Water pump rebuild
I'm trying to rebuild my 3736493 water pump for my '57 and have run into a problem. I'm using a rebuild kit from CC which includes the shaft/bearing assy and inner seal. Everything goes well until I press the cast impeller to the recommended .010-.035 gap between the impeller fins and the machined face in the housing. As it was being assembled, I hand checked the rotating torque resistance with the shaft/bearing assy uninstalled, as pressed into the housing (no detectable increase), after the inner seal is installed (maybe a 50% increase, still nothing really significant), and after the impeller is partially pressed into place (still no further increase). When the impeller is in the final recommended position (currently about .018 gap), the shaft is almost completely bound up. I've disassembled and reassembled twice with no improvement.
Any suggestions as to the cause and a solution?
An observation: The new and original inner seals are of different designs. The original is like two pieces assembled on one sleeve which would press over the shaft and seat into the cavity in the rear of the shaft hole in the body. It is rigid and shorter that the new seal, but maybe had some resilience when it was new. The new seal is longer overall, spring loaded between the two sections, one of which seats in the casting and the other presumeably presses againts the front of the impeller hub. I haven't checked, but suspect the collasped overall length is still greater than the original seal.
Don't later water pumps use a stamped impeller in place of the cast ones in this pump? Would that possibly require a different seal and could this be the source of my problem? If so, where can I get the correct early type of seal?
Thanks for any insights and help.
Any suggestions as to the cause and a solution?
An observation: The new and original inner seals are of different designs. The original is like two pieces assembled on one sleeve which would press over the shaft and seat into the cavity in the rear of the shaft hole in the body. It is rigid and shorter that the new seal, but maybe had some resilience when it was new. The new seal is longer overall, spring loaded between the two sections, one of which seats in the casting and the other presumeably presses againts the front of the impeller hub. I haven't checked, but suspect the collasped overall length is still greater than the original seal.
Don't later water pumps use a stamped impeller in place of the cast ones in this pump? Would that possibly require a different seal and could this be the source of my problem? If so, where can I get the correct early type of seal?
Thanks for any insights and help.