Gas Leak - Doodlebug

M

MtnXfreeride

New Member
#1
#1
So, I filled my Db30 with gas yesterday (full tank), rode for 3 miles and parked it in the garage. Woke up this morning to a very gassy garage. Doodlebug tank was empty and when I shoke the bike a little a few drops of stuff dripped from the air filter.

I didnt have time to investigate until after work. I took the air filter off, and the carb dome and hit it real good with carb cleaner and put it back together. The white bouy thing felt dry inside and sprung back on its own just fine. When I hit it with carb cleaner I could see it splooge from the jets real good.

Im wondering if it has to do with a little plastic piece on the top that seems to stick sometimes when I let the throttle go. Normally with the engine vibrating I bet it snaps back just fine, but I remember twisting the throttle with the engine off before I got off it last night.. maybe it was stuck?

What does this plastic thing do? Should it be this sticky (see video)?

http://youtu.be/5vzSlC6SdR0

We will see how it holds gas tonight - but tonight it sits outside while the garage airs out. I didnt get to ride it once I did the cleaning or even start the engine, so this might be a poor test.

As always, thanks for any assistance or humor.
 
Last edited:
C

chazdaddy

New Member
#6
#6
The black plastic piece is the top of the carb butterfly. It's not moving much because it stays open when the engine is stopped. If you watch it, it will close after you start the engine. The metal arm it's connected to is the governor arm.

Do you know how to close the fuel valve? :shrug:

I always close the fuel valve after I turn off the engine. I never depend on the needle inlet valve to keep fuel from leaking out the tank, through the carb. If you do a search, there is a thread about a DB30 catching fire in a garage. He's lucky he didn't burn down the whole house.

The gas leak you have is very common with these engines. I think that's why the carb has a fuel valve you can turn off. If the engine runs OK, there is nothing to fix. Just turn off the fuel after you turn off the engine.
 
C

Camjamsdad

Active Member
#7
#7
Should be as simple as turning off the fuel valve. Although the predator on my mbx11 has a bad valve. I'm also assuming your kiskstand is on the carb side of your bike. They lean when on the stand.

Fwiw the 97cc bikes were recalled because of leaky fuel caps. I know this doesn't apply to this case but just like adding useless info
 
M

MtnXfreeride

New Member
#8
#8
Camjamsdad said:
Should be as simple as turning off the fuel valve. Although the predator on my mbx11 has a bad valve. I'm also assuming your kiskstand is on the carb side of your bike. They lean when on the stand.

Fwiw the 97cc bikes were recalled because of leaky fuel caps. I know this doesn't apply to this case but just like adding useless info
Click to expand...
Hi,
I bought a chrome "improved" gas cap because the original one leaked.. the new one leaks just as bad.

Also, the fuel shut off was broken when I got the bike, the plastic is snapped off so it isn't an easy on/off for me.


Thanks above for the butterfly info. Ill test drive after work today and hopefully itll run good still.
 
C

Camjamsdad

Active Member
#9
#9
Is this a 97cc motor? Or predator? I don't know why I was thinking predator.

If the new cap is leaking I would start there first. Then depending on which motor you have I would get the parts to fix the fuel shutoff. Leaking gas isn't good when you sit above it. I think the recall involved some kids getting cooked medium rare, but don't hold me to it.
 
C

chazdaddy

New Member
#10
#10
Gas caps are problematic. Rather than buying new gas caps (expensive), I bought some Honda gas cap gaskets, appears 2 types, I bought both. Helps some, but still have to be careful to center gas cap after you put it back on, make sure both ears are engaged with the tank.

You probably won't find parts for the carb. Look for replacement carb. If you look around a little, can find for less than $20 shipped to your door.

Be safe, you don't want a gasoline fire. :scared:
 
M

MtnXfreeride

New Member
#12
#12
So after my first cleaning it held gas overnight, but the next day when I finally has time to run the engine it ran great but started leaking within minutes of shutting it off.

I took the carb off again last night and put more effort into cleaning it. Thing looks brand new inside. This time I sprayed carb cleaner into the pipe that goes to the gas tank and made sure it came out every hole on the thing.

I let it idle for a few minutes last night (too late to ride) and parked it with a paper towel underneath. Checked it an hour later and no dripping... maybe I fixed it?? But I was impatient and already ordered a replacement.
After work today Ill take it for a longer ride and see how it does.


Is it a big deal that the gasket from airfilter to carb is ripped at the screw holes it hangs on at? It still makes a seal around the carb/airfilter... I cant find replacements.
 
Ml-toys

Ml-toys

New Member
#13
#13
Sorry to bump this but i am having a leaking problem also. It appears that after sitting for a few minutes that gas comes out of the carb near the engine side. Is that an overflow on that end of the carb ?
I check the float needle and i thing it wasnt seating tightly closed, would this make the leak ?

Thanks
 
You must log in or register to reply here.
Top