I have had this motor for several years with lower unit off and on but started trying to get it running for real just recently. Fuel pump was clogged with bugs so I fixed that with a diaphram kit but didn't clean carb while I had it off. 
Haven't been happy with the way it runs lately.
I was sure the water pump I put in the housing and left on my back porch in pieces for years and finally put together was pumping water the other day. i can't remember if there was a telltale.
Anyway, the short version is no water pumping, engine temp rising so I pull lower unit and the vanes are all gone on impeller. With lower unit on the bench I decide that pushing water through pickup tube with adapters and water hose is a way to work on the powerhead with lower unit off. I hook it all up and I am sure my hose pressure is many times greater than pump pressure but cannot get a telltale stream on this old motor. Running or not shouldn't matter to the telltale because I am pretty sure this would be before the tstat.
What do you think? Good idea, bad idea? A little noisy but I only ran for a second with LU off. Ordering new impeller.
Haven't been happy with the way it runs lately.I was sure the water pump I put in the housing and left on my back porch in pieces for years and finally put together was pumping water the other day. i can't remember if there was a telltale.
Anyway, the short version is no water pumping, engine temp rising so I pull lower unit and the vanes are all gone on impeller. With lower unit on the bench I decide that pushing water through pickup tube with adapters and water hose is a way to work on the powerhead with lower unit off. I hook it all up and I am sure my hose pressure is many times greater than pump pressure but cannot get a telltale stream on this old motor. Running or not shouldn't matter to the telltale because I am pretty sure this would be before the tstat.
What do you think? Good idea, bad idea? A little noisy but I only ran for a second with LU off. Ordering new impeller.