Fuel leak from Honda 2.3 outboard

[Crinan12]

My outboard stopped working so I took the carb apart to clean it. I put it back together and it started straight away.
However fuel is now leaking, it seems to be coming from the bottom of black plastic air box thing although it's quite hard to tell.

Could this paper gasket be the culprit do you think? It has a crease on it so it's not perfect. Or is it likely something else?
There is another circular rubber gasket on the bottom of the carb bowl but it looks okay.

Thanks

 

[jamie N]

That appears to be the gasket from where the carb sits in position on the inlet manifold. I'd suggest that if fuel's coming from there, then the problem is that the needle in the carb is stuck, or not fully closing due to 'something' interrupting the the seal from it; a bit of grit or whatever, and the carb is then flooding and leaking out from there.
Possibility 2 is that there's a leak from the bowl of the carb which is difficult to see.

 

[Crinan12]

Thanks Jamie, that gasket sits on the outside part of the carburettor, where the airbox bolts on to it
The fuel seemed to be dripping from the bottom part of where the carburettor and air box join

 

[Pete7]

I think Jamie is right, the float isn't shutting off the fuel flow so its overflowing and pouring out of the venturi, then into the air box.

New gasket on e bay is about the cheapest I have found so far. Unfortunately, Steve 66 (Evans Marine) our go to guru on these engines is taking a break.

 

[VicS]

Thanks Jamie, that gasket sits on the outside part of the carburettor, where the airbox bolts on to it
The fuel seemed to be dripping from the bottom part of where the carburettor and air box join

If fuel is leaking from the joint between the carb and the air box the carb must be flooding due to the needle valve not seating properly or the float sticking or its height incorrectly adjusted.

.

 

[Gsailor]

If only 3D printing in paper or nitrile was possible ... you could print a new gasket.

I was going to suggest cutting one from gasket paper (card) and thought it looked a little tricky (but possible with craft knives and then thought “wouldn’t it be great if 3D printing in rubber /nitrile / paper was available”.

I think 3D printing in paper is available to large companies - not sure if available to Joe Public.

Google says yes, but doesn’t look very ‘gaskety’ to me.

3d printing with paper pulp - Google Search

 

[VicS]

If only 3D printing in paper or nitrile was possible ... you could print a new gasket.

I was going to suggest cutting one from gasket paper (card) and thought it looked a little tricky (but possible with craft knives and then thought “wouldn’t it be great if 3D printing in rubber /nitrile / paper was available”.

I think 3D printing in paper is available to large companies - not sure if available to Joe Public.

Flexoid gasket paper can be bought in different thicknesses but it would be a bit of a fiddle to cut especially the holes . I use a set of laboratory cork borers but the traditional method is with a ball-pein hammer

I'd not worry too much about the gasket between the carb and the air box .. but the joint between the carb and the engine would be a different matter

 

[Crinan12]

Thanks. Presumably I've done something when I've taken it off to clean it. I'll strip it down and have another look and try it again.