Mercury 4 hp

[rmorang]

sn 7127428, any info to direct me in determining year and model would be appreciated, thanks

 

[Paul Moir]

Re: Mercury 4 hp

That sound like a 4hp, 2 cylinder Gnat, with a canadian serial number. Since it's Canadian, I can only say it was made between '76 and '81. They're loopers made to compete with the johnny/rude 4hp crossflows. They failed to compete.<br /><br />If you have any questions about it, I completely rebuilt one for my brother. He uses it for pushing his sailboat around. Despite my distain for it, it has saved my arse more than once...<br /><br /> Look for GNAT here for parts breakdowns online. It's under Mercury

 

[doodad1]

Re: Mercury 4 hp

I have come into possesion of a Knat 4 SN 5672463 apparently in pretty good shape. It hasn't run for years and will surely need carb and fuel pump overhaul as well as a waterpump impeller. I am a sailor but this gnat is a short shaft. Do you think this motor is worth fooling with and can I find the parts?<br />Thanks.

 

[Paul Moir]

Re: Mercury 4 hp

Welcome to Iboats, doodad!<br /><br />First, let me be blunt. The Gnat has a reputation for being one of the worst small outboards built in recent times. But if you like to tinker and are willing to put in the time, it can run well. <br />As Merc has apparently disowned it, some parts are hard to find. The impeller is available (~$20 CDN) and should be near the top of your list for replacement. Some of the other water pump parts are not however - notably the plastic housing. The carburetor is extremely simple. Since it has a brass float and the only real seal on it is the large bowl o-ring, it can be sucessfully cleaned without rebuilding. <br />I don't think any parts are available for the fuel pump at all - the vast majority of Gnats used an internal tank and gravity fed the carb. But it's a good thing you have it because it corrects a number of problems with the fuel system.<br /><br />If you do decide to fool around with it, give me a shout at paul.moir@ns.sympatico.ca. I have a few notes that might be helpful to you.