flyrotary@lancaironline.net Mailing List Archive

Dave, The water pump turning backwards will _not_ move the water in reverse. It is not a positive displacement pump, and turning it in the wrong direction will only make the centrifugal action less efficient (and I believe more likely to cavitate) since the centrifugal force will be fighting a smaller tendancy of the vanes to force the water in toward the impeller center. The only time the vanes have any hope of winning is at _very_ low RPMs. Get the correct impeller for your rotation direction. >... So its either a broken shaft (but the pulley turns smoothly) > or something really strange (like the wrong impeller).

Well, I went out to trouble shoot the cooling problem today. The thermostat relief passage was properly sealed by my welder. Just to shed some more light on the subject I decided to start the engine with the outlet hose disconnected. I ran the engine for 2 min. and not a drop of coolant came out the opening!!! No coolant flow whatsoever, nada, zip (the system was verifiably full of coolant, the pump drive was turning. So its either a broken shaft (but the pulley turns smoothly) or something really strange (like the wrong impeller). Unfortunately, since I have less than ¼ inch clearance to the firewall I really don’t think there will be any way to get the impeller off without removing the engine. Ahg.

David Leonard

The Rotary Roster:

http://members.aol.com/_ht_a/rotaryroster/index.html