CJ Gas Return Line?

[rollbar]

On a CJ you have a gas return line coming off the fuel filter going back to the tank correct, I was talking to someone today & they said that if you remove the return line going to the tank & vent the tank return line to the charcole canister or add a check valve it will help in the performance of the JeeP/carb/engine since the carb will get 100% of the fuel that the fuel pump is delivering to it.

This makes since.

It was also stated that by having the return line you will loose some fuel that the carb may need due to the fact that the filter would be full & some fuel will go back to the tank instead of into the carb.

It was also stated that this was used for fuel savings, hummmmm.

What do you think?

Should I remove the one in Peach's 86'?

The person in question is going to remove his return line & let me know how it made a difference.

RollBar

[tufcj]

DON'T remove the return line. The fuel pump moves more than enough volume of fuel to maintain 6-7 PSI at the carb inlet and return fuel to the tank. Carbs only need that 6-7 PSI, anything more will push the needle valve off the seat and flood the engine with fuel. The big thing here is vapor lock in hot weather. By having the return line, fuel is moving at a faster rate thru the lines and has less chance of vaporizing (overheating) in the feed line. It also makes the fuel pump last longer, as the diaphram isn't trying to compress fuel that isn't flowing when the float valve in the carb is closed.

Even modern EFI systems with electric pumps use return lines.

If it wasn't needed, why would a manufacturer WASTE even $1 per vehicle to install it. It adds up to millions over the production span of a model. They do a heck of a lot more r&d at the factory than us backyard mechanics.

[rollbar]

Thanks, I'm glad I got that cleared up. I'll let him know tomorrow.

Thanks again,
RollBar

[MIDNIGHT]

Yea, don't remove it. I did trying to "clean up" under there a little and had to install a pressure regulator and a gauge, which isn't that bad, but I do have some vapor locking issues, which now I have moved my fuel line away from the exhaust to compensate so I hope it works.