50hp Merc won't pee

joblo33

Chief Petty Officer
Joined
Jan 19, 2005
Messages
501
Now that my nice 50 horse is out of commission for a while I'm digging through the pile of semi-functional outboards beside my shop and found a late 1970s or early 1980s 50 hp merc that has 122 psi on every cylinder and starts on the 1st or second pull, I'm not sure why I never sold it actually... But anyway I flashed it up and found that it won't pee, I took apart the water pump and all looks good. When I blow compressed air thru the pee hole it seems to all come out the upper exhaust hole or somewhere near there. Is there a broken valve/ plugged pipe that would cause this. It doesn't even drip out the tell tale, its dry, so my thought is that theres a clogged pipe and the air is finding its way out another way, does this make sense? any other ideas?<br />Thanks,<br />Eric
 

pegleg319

Seaman Apprentice
Joined
Mar 12, 2005
Messages
31
Re: 50hp Merc won't pee

Eric B<br />I had the same problem about 3 yrs ago, the pee hole looked ,but didn't pee, come to find out ground wasps plugged the little hole about 1/2" inside the little pipe. I removed the cowling and disconnected the water pipe and took a small wire and cleaned it out. I hpoe this can help you
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: 50hp Merc won't pee

A water pump that "looks good" as you said may very well not be good. As long as you had the unit tore down that far, why not replace it. You have an otherwise good running engine.
 

big_merc

Recruit
Joined
Mar 16, 2005
Messages
5
Re: 50hp Merc won't pee

while u have the lower unit off, there are 2 (i think) water "pipes" where the lower unit attachs to the motor, get a garden hose and spray forced water up one of these pipes (i think its the pipe that goes into the top of the water pump) and it will force its way through all the passages and come out the pee hole. i had to do this to my '74 merc 500 because it wasnt peeing at all, after i did this i have a nice solid stream....<br /><br />-Neil
 

joblo33

Chief Petty Officer
Joined
Jan 19, 2005
Messages
501
Re: 50hp Merc won't pee

I found the problem, the water pipe to the powerhead was bent, so I took it out and rebent it in a way that it's longer, works like a charm now<br />thanks
 
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