Topic: New to the Forums: Question about a gas leak.

[ScootSTC]

Hello folks,

About the bike: 1973 Honda CB350F with 3800 miles on it. I bought it last year from a Honda mechanic who needed to buy a plane ticket. He had recently rebuilt the engine and balanced the carbs, and put new tires on it. I didn't hesitate to buy it after it started cold with one kick. Everything is original with the exception of the tombstone taillight and clip-on handlebars. Even the pipes are original and in about as good as condition as I think I'll ever see original pipes. More pics to follow...

Now, the question. I seem to have a leak somewhere. I just took her out of storage after our blisteringly cold Minnesota winter. After warming up the battery and topping of the tank, she started just fine. When I was finished with the joyride I put the bike back in the garage. When I woke up, there was a leak underneath the crankcase. I was an idiot and didn't turn the petcock to "off." Even so, when I pulled the bike out from the storage shed, there was a dried pool underneath where the bike had been and the tank was more empty than when I stored the bike 6 months ago. I know for certain that the petcock was set to off during storage. I have read around the forum, and it seems that if the leak is in the line I should clamp it when storing, but what about when I'm riding? Because of where the leak was found, I'm thinking one of the carbs maybe dripping too. I am about an hour from the bike at the moment, as it is at my parent's place. When I have more time, I will definitely identify where the leak is. I am wondering, however, if there is a common error on the bike that I should look for first.

Let me know!

[calj737]

Bloody gorgeous bike!

What you may be experiencing is fuel draining thru the overflow tubes. This can happen mostly due to debris in the fuel reaching the floats and "hanging" them up, allowing more fuel into the bowl than is being used. Not uncommon for bikes stored frequently.

A really good maintenance effort on cleaning the carbs, the tank's&s interior, and insuring the bike is stored with the field tank disconnected from the bike. When you next start it up, look underneath and see if there is field dripping...

Some options: before you stop your ride, close the petcock and run the carbs empty (if storing). If you do have to store the bike for some time, empty the tank, but this creates the potential for rust to form internally. You can quickly spray some WD-40, a little splash of ATF fluid, or other rust inhibiting liquid in there to coat the inside. When riding season returns, flush the tank, fill with fresh fuel, and ride!

I doubt from looking at the single picture your bike is anything but near perfect, may just need a little bit of new season of riding TLC.

[Sdsbassist]

Cool ride...where in Minnesota?

[ScootSTC]

Thank you for the quick responses!

When you say, "field dripping", does that mean fuel dripping directly from the tank? As in, maybe there is a spot of pit rust that opened a small hole in the tank? If so, the tank itself is pretty clean from a look inside, a little rust, but nothing drastic. I'll check regardless.

I was also thinking it could be a problem with the petcock gasket, as no matter what position the petcock is in, I have found dripping.

I can't wait until this weekend when I can get home and take a look at the bike again. I'll be giving it a little work: fresh oil and filter change, maybe new spark plugs if they look fouled, but this is my number one problem.

SDSBassist: My bike is parked and mostly driven around St. Cloud. I can't wait to take it up the north shore of Lake Superior this Summer. It can't come soon enough!

[calj737]

Typo: fuel dripping. At the base of the carbs, is an overflow tube. Look there while bike is running, and also look at the petcock. Go for a ride, then come back and see if any fuels is visibly leaking while running. Then shut off bike, and check further. Finally, turn off petcock, check again.