HELP - Gas Leak from Carb "Banjo" Fitting (1 Viewer)

I have been struggling with maintaining a good seal on the brass "Banjo" fitting on my '74 Aisin carb. Today I was driving, and smelled a strong gas smell - opened the hood, and feul was dripping from the banjo fitting...

I have used new copper crush washers (top and bottom). It seems like (perhaps) the fuel line is moving slightly, and thereby loosening up the big brass center piece that compresses the washers and banjo fiitting.

Any solutions / ideas?

I didn't want to put a gasket sealer on there. Should I?

I also need to get a fire extinguisher in my rig. That gas drips right down onto the exhaust manifold.

Thanks in advance for the suggestions...

Rocky

id say get rid of the banjo fitting............go with a flare and nut.

Rocky, unfortunately that particular banjo fitting is not one of the better ones Aisan ever used. I have seen several people strip out the thread in their air horns trying to stop that banjo from leaking. You have to be VERY CAREFUL with not overtightening it.

Since the system isn't under the greatest amount of pressure to begin with, I would start by making sure that there isn't some kind of restriction in the return line back to the tank that is making the gas have a preference to leaking out thru the banjo versus just going thru the line.

Also, try screwing the banjo bolt into the air horn without the banjo fitting to get an idea of how strong of a hold the threads in the air horn have left on the bolt. If the bolt is wobbly, then the days of your air horn are numbered.

Good luck.

Mark A.

I had exactly the same problem on a small Suzuki motorcycle that I own. I put a thin layer of Three Bond gasket sealer and then BLUE locktited the banjo bolt back in. No more leaking!

Thanks for the Advice - Needle Adjustment?

Thanks for the advice.

Mark's idea on return line obstruction made sense to me, and so I disassembled
the fuel lines. No obvious restructions.

As I pulled the the banjo fitting I found there is a needle valve inside the bolt, that seems to act as a fuel return restrictor.

It doesn't look like the needle valve controlled by the carb float, since there is no way for the float to control it, also it has a screw adjustment.

I don't see anything about this in my Haynes Manual. Any advice on the proper adjustment for this valve?

Thanks again for the help. My carb has previously been ID'ed as a March '73 CA Carb (By some experts - see the attached)..

https://forum.ih8mud.com/showthread.php?t=41086

Here are some pictures of the fitting and the adjustment screw..





Thanks again.

Rocky

I am a newbie...hope it's kosher to resurect an old thread like this.

Is the return line even necessary? I have a 73 with the original carb, but I have seen some set ups with the same carb as mine with the outlet simply plugged.

If the return line is necessary, back to Rocky's last question... where should the resriction needle valve be set to?

I would like some closure to this since I have the same issues. Thanks in advance.

IOKRU2 said:

I am a newbie...hope it's kosher to resurect an old thread like this.

Is the return line even necessary? I have a 73 with the original carb, but I have seen some set ups with the same carb as mine with the outlet simply plugged.

If the return line is necessary, back to Rocky's last question... where should the resriction needle valve be set to?

I would like some closure to this since I have the same issues. Thanks in advance.

Click to expand...

if you decide to get ride of your banjo fitting ------hmmmmmmmm
i know a guy who would be glad to take it off your hands.....
my thread::: https://forum.ih8mud.com/40-55-series-tech/393809-gas-line-banjo-fititng-b-l-u-e-s.html