Fuel pump question

[CJ 74]

If my CJ sits for a few days the gas drains back to the tank there is only one line going to the carb-no return line. Would it be better to invest in a better quality fuel pump or put a electric pump on. When I bought the jeep it had several cloths pins attached to the fuel line, not sure if vapor lock has been a problem in the past. Haven't had this on the road yet hoping to retire this year and I am looking forward to taking the top off and cruising around.

 

[shum8]

Clothes pins usually indicate someone has had a vapor lock problem - And that was probably due to the fuel filter. Install one with the bypass outlet, orient it to the 12:00 position, and in theory, any vapor created will be vented via the bypass line. Typically make a big difference.

As to your fuel draining back to the tank - sounds like the fuel line is sucking air - either thru a crack in the line, or possibly in the fuel pump diaphragm. I'm sure someone will be along shortly to help with that one.

 

[Posi]

His year didn't come with a return line so he wouldn't be able to run the newer fuel filter unless he swaps to a newer sending unit as well.

Do you have the stock YF carb?

 

[Torxhead]

Are you sure it is draining back into the tank? If there is no fuel tank vent a vacuum in the tank will develop though. Another possibility would be gas leaking out of the carb. The mechanical fuel pump might have a pressure problem and there could be an issue with cracked fuel lines.I don't think a complicated electric fuel pump addition would solve your issue completely.

 

[Lumpy Grits]

Where is the fuel filter positioned/located to the carb?
Can you post a picture for us?
LG

 

[CJ 74]

I was thinking fuel pump diaphragm. But the line sucking air may be the problem, the pump looks new but the line is only threaded to the pump it's cut just before the carb and has rubber hose connecting the line and carb. May be getting air there. Not sure if it's a YF carb that's on it but posting a picture is a great idea, I will have one posted tonight when I get home. I guess I am not sure if the fuel drains all the way back to the tank but I have noticed the longer it sits the longer I have to crank to get it started, just assumed it was draining past the pump. Love this site, you guys are awesome.

 

[Lumpy Grits]

Bet the fuel is draining out of the carb's bowl.
LG

 

[CJ 74]

If the jeep sits for a couple of days the gas seems to drain back down the line with nothing remaining in the filter. No leaks that I know of and no smell of gas. To torx heads question the gas cap is not vented

 

[Lumpy Grits]

Those clothes pins do nut'n for you.
I would NOT use a plastic fuel filter that close to the exhaust system.
LG

 

[CJ 74]

That's what was on it when I bought it. Going to get a metal one this afternoon, thanks for the help!

 

[Lumpy Grits]

Route it away from the heat side of the engine.
Mine is on top of the v'cover.
LG

 

[CJ 74]

Installed a vented cap and the gas draining back has not been a problem since. Thanks Torxhead!

 

[Lumpy Grits]

THX for the update.
LG

 

[CJ 74]

Forgot to add, I replaced the fuel filter with a metal one and roughted it away from the exhaust manifold. Thanks!

 

[Lumpy Grits]

NP-
LG