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Mercury 25hp water leak at shift shaft

K

Knightg

New member
Hey guys I am having an issue and wanting to know if its a big deal or not. I just replace the impeller and gaskets on a 1999 mercury 25hp. When I bolted it back up and hooked the water hose to it I noticed that was was spewing water from the exposed shift shaft area in the lower unit. Its peeing through the indicator fine, just leaking a lot from the exposed area of the shift shaft. The pump housing o-ring that came with the kit was a little too big for the pump housing and I couldn't get it to stay in the top cover very well when I put it together. Another detail is that my water pressure at my house is 80-100 psi due to bad regulator. Maybe this is beyond the working pressure of the water pump seals and causing a leak out the shift shaft area. My question is this: is this a problem? Can I run it like this as long as its pumping? How do you get the o-ring to stay in the correct location when installing the pump housing on the impeller? Thanks in advanced fro any help.
 
Update. I removed the lower unit again and checked to make sure the water pump was installed correctly. After I put the impeller on I spun the drive shaft clockwise while pushing the housing down on the impeller. The water pump only pumps intermittently through the pee hole. It will pump a good stream for a little while then kind of spit for a little while. Could something be clogging the waterline somewhere? I can blow through the indicator line and the air moves freely. I'm not sure what is going on, and really need to get this fixed before a fishing trip this weekend. Any help is greatly appreciated.
 
Could simply be the thermostat operating? Can you KEEP your hand on the left side exhaust cover? If so, it's okay.

Jeff
 
I am thinking you are right Jeff. I ran it for about 3 min and the head got around 125º F. I'm guessing this thing has a very precise thermostat that activates and deactivates under slight temp changes.
 
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