[bsevans]

Originally Posted by mike@dw

Ok, I have done some more investigating.

My 40 has a 350, and all the emissions has been removed including the charcoal canister. They way it is set up is just a single feed line to the carb. No return line and no venting system. There are a total of 3 lines coming out of the tank that are capped off. Those three caped off lines I am assuming are the return and the two venting lines for the emissions. I would also guess that the gas cap is not a venting type cap either.

I think this is the reason behind the gas smell. I think I either need to rig up a line to a home made charcoal canister or get a venting gas cap. The vapors have to go somewhere, and right now they are just seeping out and getting into the cab.

If you find a venting gas cap that properly fits, then post up the part number. I looked for one and none of the major suppliers made one. Here in Tucson and Phoenix one would need to hold on to the factory cap as a cap that vents will fail inspection They pressure check every gas cap. You must make sure that you do not drain gas into a charcoal canister. That is the reason the vapor recovery tank had the three lines that are capped going to the bottom of the vapor recovery tank and the line going to the canister was attached to the top of the tank. I recently replaced my vapor recovery tank due to a cracked port which allowed gas vapor into the cab. These threads will show you the basic arrangment of the ports.

Custom Vapor Recovery Tank

Factory Fuel Recovery