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Boss gasket on 1972 4hp carb do I need it

T

tomf

Regular Contributor
"Hi all,
doing a carb rebuil

"Hi all,
doing a carb rebuild on a 1972 Johnson 4 hp. I've cleaned out the carb and am ready to put it back together, however I noticed that the carb didn't have a boss gasket on the high speed nozzle (part #21 in this pic):http://www.marineengine.com/discus/messages/12478/220660.png"" alt=""1972 Johnson Evinrude 4 hp carburetor"">

There is one in the carb rebuild kit and it fits on the nozzle, but the carb bowl doesn't fit on with it, there is a gap of about 1 or 2 mm above the bowl gasket.

I'm not 100% familiar with the operation of this carb yet so I'm not sure whether the gasket should be there. The motor seems to have been maintained somewhat sloppily (carb installed without an intake manifold gasket, some packing missing from the needle valves etc.), so I wouldn't be surprised if the previous owner had just misplaced one of the parts.

So should just leave the boss gasket off, as the carb was before, or trim the one in the carb kit to size and install it on the nozzle?"
 
"OK, suspected as much, thanks

"OK, suspected as much, thanks for the confirmation. I'll just shave down the one in the kit then to get a good fit & stick it back together.

Damn, I wonder if that missing gasket might have something to do with the fact that gas seemed to be oozing everywhere the first time I tried to start the motor... LOL
rofl.gif
"
 
Don't 'shave' down

Don't 'shave' down anything!!!
The gasket gets compressed to correct thicknes when bowl is tightened.
 
"Thank you, Morten, you just s

"Thank you, Morten, you just saved me from making an even bigger ass of myself.
happy.gif
I don't know where I got that idea from, the gap just looked so big I thought the bowl would never screw on. Figured maybe the gasket was a slightly different size since some of the small carb parts appear to be different between my euro-made engine and the diagrams on Evinrude's parts lookup. Or something... whatever.

But of course, it went on fine, no problems whatsoever. Issue solved!"
 
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