Johnson 140 hp Impeller Replacement

[AguaSki]

Last year I successfully replaced my impeller for the first time, so I thought I would tackle it again today. I had an overheating problem a few weeks ago, so I thought I should go after the impeller again, but normally I would wait a couple years. After reassembling everything I connected the motor to the muffs and fired it up. Instantly I noticed no water coming from the tell tale and the other discharge points, so I shut the motor down. Now what? I ran out of daylight, so I could not work on the project any longer, but here I sit thinking about it. It will be until at least next Saturday before I have time to drop the lower unit again. Since this was my second time doing the impeller I did not reference my manual like I did the first time, so I am wondering if I missed a step or assembled something incorrectly. The success from last year may have had me a little overconfident. Just out of curiosity, are there common ways that rookies reassemble the water pump that may not be correct? I am wondering if the key slipped some how. I know the only way to know what is really going on is to drop the lower unit again, but I have week to stew about this, so I thought I would fish for feedback.

BTW - It did not appear that my impeller was the reason for the overheating. I also put in a new thermostat kit today. The old valves and thermostats looked really bad. I am confident I got all the thermostat parts back in correctly.

 

[james williams]

Re: Johnson 140 hp Impeller Replacement

Did you put the key in? I did a water pump yesterday. They say you can not put the impeller in backwards.If you could and if you did,the key would come out.If nobody else tells you anything,any different,I would take it back apart.Maybe some body that knows will answer your call.Did you get the tubes correct? james

 

[AguaSki]

Re: Johnson 140 hp Impeller Replacement

Problem fixed, but I thought I would share what I found. I did install the key, but when I slid the impeller over it I must have knocked the key out of the groove. This had the shaft spinning, but the impeller was stationary. When I pulled everything apart the key was just laying between two of the impeller blades. After getting everything put back together correctly, I had great water pressure and a strong pee stream.