Anyone here ever own/work on a Nissan 5hp OB motor?

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BloodStone

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Hello;
Back in February I purchased a 1988 Nissan 5hp (#NS5B). Looked great, started great, great compression, lower unit oil was great etc.. Anyway, the catch is..It's not pumping water (feel air but no moisture). I removed the lower unit, took off the pump housing bolts & low & behold there was the impeller..in pieces (3.5 blades out of 5-not good!). Found a small piece of the impeller & removed it. And Naturally, I replaced the impeller, put it all back together (what a royal pain in the arse that was!), placed it in a 35 gallon barrel, filled it with water, started the motor &... TA DA- NOTHING! Lots of air but, again NO water. After talking again to the local Nissan dealer (& wondering if perhaps I put the impeller in upside down :oops: ), I took out the impeller, turned it around & put it all back together again. Started it & ZIPPO! Lots of air but no water :-x . The water pump housing is in great shape (ditto for the wp gaskets). And I blew a small amount of air through the motor (20lbs or so). So someone PLEASE tell me they have some idea/suggestions what in the world is going on? Don't really have the ca$h to doll out for the marina to fix it. And yes, I made sure the chuck/key was properly placed on the shaft both times.
Thanks in advance.

P.S. I viewed both of the engine boards here & at iboats (plus youtube) before posting. Lots of helpful tips but no exact answers to my specific problem).
 
Sounds like theres a chunk of impeller blocking the water passage somewhere. Blow some air in the pee hole to make sure it doesnt have a blockage there. Take the lower unit off and check the water intake passage and the water tube for blockage.

Steve
 
you need to make sure the blades to the impeller are facing or turned the right way,,,, get the manual or look on line the direction of rotation has to be right,,, you said you turn it over not sure what was meant by that
 
All things stated above, I was going to say. One last thing, does it have a thermostat? If it does, you will have to wait foe the motor to warm up before the water will come out of the pee hole. I don't know that motor, but it may have one.
 
Update:
After many trials & tribulations (aka taking apart the LU & putting back together 4-5 times), I am happy to report, that I FINALLY got the motor fixed & all is right in the fishing world. =D> On a side note; I think, no I KNOW, it would've been an easier endeavor had I had some sort of service manual given the fact that this was my 1st ever impeller/WP repair. Also having a friend assist (I.e an extra set of hands & eyes) doesn't hurt none either.
Thanks again to all those who responded.
:beer:
(now onto the next project.... 8-[ )
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=349840#p349840 said:
Rat » 47 minutes ago[/url]"]So...what was wrong? Or are you gonna just keep it a secret from all of us? :mrgreen:


Wondering the same thing.. :-k
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=349840#p349840 said:
Rat » Wed Apr 23, 2014 3:54 pm[/url]"]So...what was wrong? Or are you gonna just keep it a secret from all of us? :mrgreen:

Well... as I stated initially, the impeller was trashed. Found a sliver of it & removed it. Put the new impeller in, put the lower unit back on & WALLA, nothing. Took it apart again, blew air & water from both ends & it passed both without even a sputter. Tried the drill on the end of the drive shaft trick & that didn't do a whole lot either. Then, we thought that the Nissan dealer might have sold us the wrong size impeller due to how bent over the fins were inside the wp cup. Took the whole wp assembly in, he looked at it & said;"nope it's the right one". And then the guy behind the counter asks; "where's the rubber grommet that the water pickup tube slides into that's on the WP housing"? BINGO! It was shoved all the way up the tube to almost the where the drive shaft connects into the engine #-o . In our defense, it was so **** hard trying to get any kind of light focused in there to see what the heck we were doing (we ended up using a small pin light & tied some fishing line on it that we pulled out once everything was lined up-wish we thought of that earlier).
And once we got that little grommet detail corrected, that was it. Now, it runs just fantastic (even on the slowest setting) & "pees" with all the intensity of a man who has just downed a couple of 40s. :D
 

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