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Carb leaking gas. Wrong fuel filter?

Carb leaking gas. Wrong fuel filter?

Gungho

Jeeper
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Location
Atlanta, GA
Vehicle(s)
'78 cj5 258 straight 6, 3 speed manual, hei distributor, motorcraft 2100 carb with electric choke.
I've been chasing a gas smell that happens after driving my jeep. I've found where gas is coming out of the carb. It's not dripping out that I can tell, but enough to see it on the carb and definitely smell it. One thing I noticed when investigating, is that my fuel filter looks different than most 1978 cj's. It looks more like one from a 75. Here are some pictures. Any idea how to get the gas leak under control?
 
Yes you have the wrong filter it should have one inlet and two out lets with one of the out lets returning fuel back to the tank. With out the return line it building up to much pressure and blowing fuel past the neddle and seat in your carb.
 
Along with what was just said, on the top of your fuel tank, next where the main fuel hose is there will be a 1/4" nozzle which hopefully is plugged off. This is where the fuel return line should go that the correct fuel filter has on it. There could be just a few loose screws on the carb float bowl making that carb leak fuel also.
 
Thanks for the help. Where can I get new hose to run if I have to? I found one hose under the hood that's plugged off. I'm hoping that's it.
 
You should probably trace down that line which should be for a 1/4" hose. A local auto parts should have the fuel line that you are looking for and it is sold by the foot. The extra outlet on the fuel filter is placed at the straight up or 12:00 position. That extra line was installed for excess fuel pressure or vapor lock. Previous owners come up with some great stuff to make their rigs better, I wonder what the guy who ends up with my rig is going to think of its p.o.?
 
Thanks for the help. Where can I get new hose to run if I have to? I found one hose under the hood that's plugged off. I'm hoping that's it.
It should be a metal line running back to the tank with a 2 to 3 foot rubber line from it to the filter. It runs done the driver side frame.
 
That plastic filter, above the exhaust like that is a fire hazard!

Even the OEM metal one was well known for the cause of engine fires, because of leaking rubber attachment hoses.

I would strongly recommend you find a copy of the real factory service manual(FSM). It will have all the fuel return routing info you need.
1979 Jeep Service Manual (Body/Chassis) ? CBJeep

LG
 
Ok, so I replaced the fuel filter with one that has one inlet and two outlasts. What a typical CJ filter looks like. It ran fine for 10 minutes and then sputtering. Looked under the hood and the carburetor was leaking a lot of gas. It's a carter yf carburetor. Any ideas? Is it possible this carburetor uses the one in, one out fuel filter?
 
You need to rebuild that carb, as you have a serious fire hazard on your hands.
LG
 
It's not going anywhere until I get this figured out. It looked me like this carb uses a different fuel filter. I'm thinking to just buy a new carburetor. Any recommendations for carburetor for AMC 258 i6 / 4.2l years engine. It will mainly be weekend driver
 
A new carb may not be tuned for your altitude/engine. Learn to rebuild what you have. Carbs need to be gone through every couple of years anyways. It ain't hard and there's plenty to read via GOOGLE.
Lot of the 'new-carbs' these days are china knock-offs and are a total POS.
LG
 
I have a Carter AFB on my 360 and it displayed similar issues. After a rebuild the leak persisted until I found that the rebuild kit had the wrong fuel inlet valve where the float needle regulates the fuel. Once I got a handle on that, she's purring like a kitten.
 
Picking up a 78 CJ7 next week. Carb is flooding too. My dad's been working on it for me. He said it only has one fuel line also, no return line. It ran fine before it sat for about two years. The only thing different is they replaced the mechanical fuel pump.
 
I switched my fuel filter to the proper one with a return line and this helped a little. Ultimately I had to replace the carburetor to completely fix my issue. I think I had a few different problems going on.
 
It's a pity you had to replace that carb, in my experience those YF's are a breeze to rebuild, very simple in design. I had one of these atop my 300 in 'Easy Bake' a black panel Ford van. The only quirk I had with that carb was a little bit of sticky carbon built up around the choke butterfly causing the motor to chug chug. Since the carb on those vans are located right at the cusp of the engine doghouse, it was impossible to discern what the matter was until I removed that carb, and cleaned out the barrel.
 

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