Gas leak

[dwkamins]

Seems I am loosing gas through the carb. It seems to be siphoning out until it balances itself (it that makes sense). With the tank full, it will be down to about 2 - 3 inches left in the tank after two weeks.

It's also been flooding and hard to start.

I have a carb rebuild kit.

runs fine once it gets going. maybe a little more smoke.

any guidance would be appreciated.

thanx dk

[backyard]

Are there any visible leaks in the fuel line, filter, pump area, carb connection?

If not, then there probably is a needle valve inside the carb that isn't fully seating allowing the gas to run out of the carb into the intake. An easy way to test this is take the breather hose off and see if fuel just runs out of the carb while it is not running. Don't test in the hot sun or the gas may evaporate before you can tell.

[73eldo]

Is this a diaphragm carb like a Tilotson? Or a float bowl like a Walbro?

[dwkamins]

Yes, I can see fuel on the frame under the Carb area.

This is a '75 with the Tilotson with pump in the carb.

I will start with taking the Air Filter horn off and take a look.

any more info / advise is welcomed!!

Thanks dk

[73eldo]

Take it apart, clean it, and install the parts from the kit. You may just have dried up gaskets. Another thing I have seen on these is where in the past someone has really cranked down on the screws that hold the sections together. What this does is kinda pulls the threads up and leaves a raised area around them so the gaskets can't seal. A little careful work with a fine file or emery cloth on a flat surface like glass will take down the high spots and solve the issue. You can see it as you work because at first only the high spots will show the scuffing. When you get lite scuffs across the whole surface its flat.

[dwkamins]

Perfect instructions. Thanks!!

I'll try it next weekend out at the campsite.

Want to install a fuel shut off valve also. What is the gas line size? 5/16? I know it's the larger of the two popular sizes for gas lines.

Thanks again!

[forge5813]

Here is a pic of how I did mine. I used 1/4" id line with a 1/4" shut off and in line filter.

[dwkamins]

Very nice set up!
My engine looked like that a few years ago after a total rebuild. . . but now being out at the campsite, dusty and dirty.

so how do I mount a nice K/N filter on to the carb like that?

Ever think about placing a dust bag over the filter? Like the ones dirt bikes use.

Is that a Toltison carb? (standard for '75)

Thanks for the photo on your set up.

[forge5813]

Mine is an early 1970 and has the stock Tilotson carb. The K & N filter just clamped right on the intake flange but I had to size it accordingly in length and diameter from a list of the hundreds of filters K & N offers. I don't see a need for a sock as mine won't be used much in dusty conditions. I can get you the K & N part number that I used if you want, as it should fit a '75.

[dwkamins]

Thanks for the info. . . I do have a K&N right now. . . in the original filter housing.

It comes in handy as I am washing and recharging two or three times per summer.