water stopped pumping out pee hole

[Virginboater72]

Hey guys, I hope you are all doing well. I am still fighting with the 1987 60HP Mercury OB that I had trouble with a week ago. A quick recap: I removed lower unit because it stopped pumping water and I didn't know when the impeller had been changed last. I cracked the housing removing the LU, and ended up getting a used one with a new pump and impeller. I put everything back together, fired it up, it wasn't overheating anymore, there was a strong stream of water coming out, it shifted a little hard, but it went into fwd and rev okay, I thought it was fixed. I fired it up yesterday, no water stream and it's still overheating. I removed the water hose from the top of the head to make sure it wasn't plugged, and I blew through it and could hear air coming out LU so it appears to be clear. I'm at a total loss now, any ideas?

 

[christroutner]

Re: water stopped pumping out pee hole

Check the impellerer again. It doesn't take much to shred them or melt them. I heard that 10 seconds running dry is enough. Even after you get this fixed, it's always a good idea to have a spare impeller and the tools you need to change it onboard.

 

[Virginboater72]

Re: water stopped pumping out pee hole

It looks like the impeller may have gotten dry/or hot and stuck after I shut it down last time. It seems to be freed up now. I seem to be having a problem with the shift shaft lining up with the control arm at the top end of the shaft. When I push the LU up, I have to rotate the shifter arm to line up the splines so it seats properly on the top. If I shift it into reverse, the control arm lines up with the splines on the shaft, and it will go together. It's almost like the LU is in reverse or fwd. Anybody understand what I mean? I'm not sure if I'm explaining well enough.

 

[quicktach]

Re: water stopped pumping out pee hole

The impeller's still not right. Dry/hot/stuck shouldn't happen after a shutdown. I'd take it apart and redo it, putting in a new impeller. A good trick is to drop the LU in neutral with the shift mechanism in neutral ....and keep it there and reinstall in neutral. Sounds like you dropped it in gear....

 

[oldman570]

Re: water stopped pumping out pee hole

Running a impeller dry will fry it in just 5 seconds at times. The seal rings on the impeller close to the driveshaft are small and if the upper cup and lower plate had ware rings groved into them, there is a good chance that also added to the trouble. Time to tear the LU off again and replace the impeller and the cup and plate if not done the first time. When running the motor on muffs will not tell the real story about the impeller as the water pressure from the hose will force water to the motor and cause everything to look fine.
You did get the flat key in the shaft and impeller correct , and it not fall out of place when putting the waterpump back together. This could also cause the trouble as it could have fallen out of place and ended up between the fins of the impeller. JMO
Oldman570