OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Tech Talk Chonda - Sanli Lazercut!

The GXV140 has a D-shaped intake port, which shows you which way to put on the gasket on the port side of the insulator. Then you put the insulator on with the air passage positioned away from the engine, toward the carburetor, and with the entry port for the air passage facing downward so it won't collect dirt, and the matching port in the carburetor in the same position when you install it:


Note the yellow oval on that picture. Put the hole in the second insulator gasket over the top of that yellow oval, so that it communicates with the clean end of the air passage in the insulator.

Then there is only one way you can put the carburetor on, unless you want to have the float bowl upside down:


Now unfortunately I feel obliged to explain what all that stuff does, which will condemn this thread to ending up in Tech Talk.

The carburetor appears to have been designed for that system to be the float bowl vent. Here is a top view of the carburetor:


The yellow oval shows the path of the horizontal passage in the carburetor, of which the port we have been looking at is the end point at the right hand end. The red circle shows a vertical passage down to the float bowl compartment, matching that horizontal passage.

Now let's look at the underside of the carburetor, above the float bowl:


The red circle shows the underside of that vertical passage that we've just examined from the other end. If you look at it very closely, you'll see that there is no lateral port at the bottom of it, heading off to the left, toward the port in the carburetor's mounting flange. I've verified this by probing the passages: the passage from the flange to the vertical passage is blanked off. After providing elaborate tooling in the insulator and the carburetor mounting flange, plus the horizontal and vertical passages in the carburetor, Honda decided not to use them, probably because of the possibility of dirt entering the float bowl through that system. Hence it seems it makes no difference whether you misassemble that system or not, since it isn't being used.

So how is the float bowl vented, I hear you cry? Check the green circle. This is the actual float bowl vent, which communicates with the air cleaner, and thus does not allow dirt to enter the float bowl. Note that all this does make it important to put the air cleaner mounting parts together the right way around.

I must confess I didn't know until I did this check this morning, that the air passages in the insulator and flange are dummies - so the exercise has been interesting, and perhaps useful.