Gas leak

BulletBob

Member
Good evening BDB,

I have a 2006 Big Dog K9, it was my father's bike. He wasn't able to ride anymore so I had it shipped to me this summer. I had a full inspection, new cables, new tires, hoses, carbs done, etc to get it running again. It was stored in a temp controlled facility for a few years, drained dry before storage. I always pull it out of the garage and start it, let it run for a bit each week (still need to get title/tags/etc). Today I did the same and brought it back into the garage. An hour later, I walk into the garage to find gas all over the floor. I checked the hose (brand new) from the On/Reserve down, under the gas tank and dry as a bone. Any ideas on the problem? The fumes were so bad that I hosed down the garage floor immediately so I cannot tell where the gas was leaking. The only wet spot I could find was on the clutch side of the bottom frame.

Thanks in advance from a newbie.
 

BulletBob

Member
Thanks for the responses. My father said he kept the petcock in the on position for 7 years with no issues. I turned it off as soon as I saw the gas all over the garage floor.
 

awg

Guru
Mine did the same thing. When I turned the fuel to the off position, it wasn't shutting off. The O-Ring in the petcock wasn't doing its job. Fuel flowed out of the overflow tube. Had the petcock rebuilt, and took the bowl off the bottom of carb and worked the float up and down and sprayed carb cleaner in there. Works fine now.
 

woodbutcher

Mr. Old Fart member #145
Staff member
it's that little bitty clear tube that runs from the carb down toward the bottom of the crankcase so it dumps on the ground. if it is an '06, it has probably tuned yellow by now.
 

MossBerg590

Active Member
Thanks for the responses. My father said he kept the petcock in the on position for 7 years with no issues. I turned it off as soon as I saw the gas all over the garage floor.
That's not a good habit for 2 reasons, one is if the float decides to stick then you'll end up with fuel all over the floor like you did...two is if it sits for a long period and the gas goes bad, it's better to be able to just drain the tank then get the carb gunked up and have to take it apart and clean it. I would pick up a rebuild kit and clean the carb out real good
 

awg

Guru
it's that little bitty clear tube that runs from the carb down toward the bottom of the crankcase so it dumps on the ground. if it is an '06, it has probably tuned yellow by now.
Yep. They dry rot turn yellow and get hard. It will drain some where under the bike.
 

BulletBob

Member
Thanks again for all of the replies. I finally got the gas smell out of the garage (was coming into the house as well). :)
Pulled the bike outside and ran it, left the fuel on after shutdown and it drained out again. As I mentioned earlier, carbs were done and hoses replaced, etc but I guess the float is still stuck. Here are some pics of the bike.
IMG_0551.jpgIMG_0553.jpgIMG_0554.jpg
 

awg

Guru
Try turning off the fuel and run the bike till it runs out of fuel. If it keeps running for a long time my guess is the petcock isn't shutting off the fuel. And if the float is sticking you will drain the tank.
 

MossBerg590

Active Member
I missed the part where you mentioned the carbs were recently done. It's possible the floats are sticking or got tweaked out of adjustment. Even if the petcock wasnt closing properly it shouldnt leak if your floats are adjusted and working. You can try lightly tapping on the carb bowl with a rubber mallet to see if it gets the float unstuck or just drop the bowl and inspect.
Nice looking bike btw
 

Jersey Big Mike

100K mile club
Try this
Start the bike
Trun off petcock and let bike run till it stalls
tap on the bottom of the carb
turn on gas and restart
Shut off and see if it still does it.

My Mikuni used to get dirt in it and the float would stick every once in a while (after work done ususally) and this was the fix.
 

BulletBob

Member
Great feedback and thank you again from this forum and the nice comments. What a wonderful place to get information on these bikes. :old2: I'm traveling all this week but will plan to try the above next weekend.
 
Large amounts of oxygen in ethanol blended gas causes gas to decay faster so these days one should never leave fuel lounging in the fuel system for very long. As stated earlier everything gets varnished and gunked up which leads to these types of issues. Gas and milk are both organic and they decay in the same way so just imagine if you left milk in your fuel system....lol.
 
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