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Fuel leak from overflow tube

Stratkat

Stratkat

2012-09-12 02:58:00 UTC

before people get pissed off here yes i did a search and have read everything pertaining to this. i just replaced my coolant hoses now its leaking from the overflow tube on the left hand side of the bike (no, while replacing the coolant hoses i did not lift the tank). ive never removed the canister.

people on here say this can be cause by a blocked tube. how?
what is blocking the tube? what am i looking for?
take the tubes off and blow them out??
is the tube pinched? if its "pinched" or "blocked" how is fuel flowing out of it in the first place and onto the floor???
no one really says what to do, more like "ah found it, the tube was blocked..."
this bike is killing me lately!

MADDOG53

MADDOG53

2012-09-12 14:18:00 UTC

Mine did the same thing,,,blew out the canicter and all was fine,,,,,,,,,,,

Stratkat

Stratkat

2012-09-12 16:27:00 UTC

how did you do that Maddog? compressed air?

MADDOG53

MADDOG53

2012-09-12 16:38:00 UTC

Post missing.

Stratkat

Stratkat

2012-09-12 23:22:00 UTC

im getting a compressor this week to paint a few guitars, ill let you know how it worked, thanks

Willh

Willh

2012-09-12 23:40:00 UTC

Holy shit man you, still have the canister

Stratkat

Stratkat

2012-09-13 12:40:00 UTC

yep.

tigerstyletroy

tigerstyletroy

2012-11-05 21:00:00 UTC

Instead of starting a new thread i figured i would just bump this semi recent one. After riding to work through some heat (maybe 90 deg F) then had the bike sitting outside under the bike cover i noticed it started pissing fuel out of the dangling hose. This only started after the bike had been siting for an hour or so and seems to only happen during the day? There were no marks in the garage this morning. It happened today and yesterday exactly the same, however today it leaked out quite a bit more. Both times i had filled the bike up in the morning before my ride. The ride is about 30 miles so i use quite a bit of fuel so i dont think the tank is full enough at the end of the ride to be overflowing?

Image

MADDOG53

MADDOG53

2012-11-06 00:26:00 UTC

Is the tank "presurized" when you open it make sure there are no kink's in the lines

tigerstyletroy

tigerstyletroy

2013-01-19 20:33:00 UTC

Alright, bumping this thread again. Been difficult to test since its been so cold lately but with temps near 80F today it started pissing again. Employer was real unhappy as they just painted the parking lot and the gas made a good mess of the fresh paint. Remembering your advice I went to check the fuel cap and upon sticking the key in I hear a slight hissing and then a gasp for air as its opened. Observing the gas...looks like its boiling inside. Have not had the tank off at all as of yet, soon to change, so pinched lines is out of the equation. I guess when I get home ill pull the filler cap apart and check the seals/ blow some air through it. As far as aftermarket...what have you got Maddog? The aftermarket vents better than stocker?

MADDOG53

MADDOG53

2013-01-19 21:40:00 UTC

This is the one I installed,,,hasn't pissed since,,do you still have the carbon canister

tigerstyletroy

tigerstyletroy

2013-01-19 23:11:00 UTC

Still have the canister yes. You think it is somehow related? I know its super easy to get rid of, just havent had a need to until now I suppose.

MADDOG53

MADDOG53

2013-01-20 12:58:00 UTC

Post missing.

tigerstyletroy

tigerstyletroy

2013-01-20 17:56:00 UTC

My 08 SD has two tank vents. One on the left front side as you sit on the bike. The other on the right rear. The rear line ran back to the carbon filter. Now it runs out to the left side. I installed a solo seat last month and removed the can in the ass for room to haul tools, like the bike was origionaly designed. Both tank vents can be seen and checked for flow by opening the filler cap. Find the other ends of the tubes and blow in the lines to check for flow at the filler cap. You might have a pinched line from a too tight zip tie or a mis-routed tube. The area at the rear of the tank is really crowded and is a likley location. This location caused a gas leak on my bike when I rerouted tubes when I removed the can in the ass. The fitting that comes out of the tank was leaking and ran gas down the bike frame and on the floor over night. The gas even filled up the spark plug wire casing. I pulled the pulg wire off and poured gas out of the spark plug wire casing. I was able to twist the fitting so the fitting made a better seal,and the tubes had a clear path and it quit leaking.

On a hot day with a full gas tank it is possible for the gas to fill the can in the ass. That expelled gas in the can of the ass has to come out some how. As the day gets hotter I can see the tank building pressure and blowing the gas out of the can in the ass.
One fix is never top up your gas too full and let it stand in the hot sun.

MADDOG53

MADDOG53

2013-01-20 18:26:00 UTC

Well today after my ride I cracked the filler cap to relieve pressure then put the cover on. If it doesnt piss, then its an issue with the filler cap not venting properly...right? I checked the mentioned hoses and could find no kinks or overbearing zip ties so that's not the issue unless I missed something.

tigerstyletroy

tigerstyletroy

2013-01-20 18:48:00 UTC

Good idea Doug,,,,,never "top it off" and leave her in the direct sun,,,,

tigerstyletroy

tigerstyletroy

2013-01-20 20:16:00 UTC

Well by the end of the ride tank is about 2/3 full probably. Unfortunately there is no shaded area to park so I have to make due with my motorcycle cover.