Leaking fuel out of Pods

Went for a run today and when I got back the carbs started leaking fuel from the pod filter. It was leaking out of the left most pod. I believe this was just because it was the lowest one (bike was on side stand). This is only the forth time riding the bike and this never happened after other runs. Not sure if it's related but this is the first run I did where the tank was completely full. The other three runs the tank was less than half full. Also, the third run I had to switch to Reserve. Would gunk sucked in during reserve impact the petcock?

I have to leave town tomorrow and so I didn't have time to take anything apart to diagnose yet. Since the bike is stored in a garage attached to the house I needed to drain the fuel from the tank and carbs just to be sure it wouldn't continue to leak while I was gone.

After draining everything I noticed that the vacuum line attached to the petcock wasn't really on very tight. Could this cause the overflow problem? If the vacuum line is not sealed totally will this cause issues? As it was the petcock was in the On position and everything was still leaking. So I'm guessing that either the petcock is toast or the vacuum line is the culprit. Does this sound correct? Or is there somewhere else I should be looking?

Any help would be appreciated.

The Petcock shouldn't flow gas with no vacuum applied to it unless it's in the prime position. first fix the petcock and then move on to the float valves and needles in the carbs.

Doug.

Am thinking this doesn't relate to amount of fuel in the tank or gunk in the petcock or a loose vacuum line.

Would check overflow circuit in #1 carb. If a leaking float needle keeps allowing fuel into the float bowl, and excess fuel isn't able to escape via overflow as designed, the escess fuel may rise up into the carb throat and flow backwards and out the pod filter.

Excess fuel in the carb throat also flows forward toward the engine, where it may enter the combustion chamber and drain down around the piston and rings into the crankcase. And thereby contaminate the oil.

Would sniff-test the crankcase oil. And keep an eye on the oil level, which may "rise" due to the fuel intrusion.

Would assure correct functioning of the floatbowl overflow circuit, and proper operation of the float, and assure that the float needle/seat interface isn't leaking (often due to grit or crud at interface of seat orifice and tip of float needle).

The objective is to have the floatbowl overflow circuit functioning as it's supposed to (i.e., by allowing any excess incoming fuel to drain out through the nipples on bottoms of floatbowls and on through the drain tubes to underneath the bike).

If Mikuni smoothbores are fitted, they do not have floatbowl overflows, so special care should be directed toward assuring absence of excess fuel into the floatbowls.

Am uncertain, but have heard that a damaged diaphram in a vacuum petcock may allow fuel to run down the vacuum tube and into the carb throat.

If in doubt about whether fuel has intruded into crankcase, should change both oil and filter.

Good Luck!

Thanks guys for the great responses. That'll give me some things to check when I get back next weekend. Just hate the fact that I have to go away and can't revisit it until next weekend.

I couldn't sniff test the oil yesterday as there was already too much smell of gas around that I wouldn't be able to tell. I think I'll change it anyway just to be sure, don't want to risk that. Hate problems that involve gas as the smell gets everywhere.

Thanks again, much appreciated.

The only time I've had fuel leaking out the pods, was when I had the fuel hooked up to my overflow tube:blush: Funny thing is that it actually ran,:blink: until it flooded, then the gas poured out the pods.

The issue most likely is due to a bad vacuum hose which causes your petcock to not work as it should. If it doesn't shut off, the float valves are the only thing that keep the carburetors from leaking and when you park on the sidestand, your #4 carburetor is prone to leaking. To test the petcock, just remove the fuel hose when the bike is off and parked. If gas comes out, either the petcock diaphragm is bad OR the hose connected to engine vacuum and the petcock is compromised.

wiredgeorge wrote:

The issue most likely is due to a bad vacuum hose which causes your petcock to not work as it should. If it doesn't shut off, the float valves are the only thing that keep the carburetors from leaking and when you park on the sidestand, your #4 carburetor is prone to leaking. To test the petcock, just remove the fuel hose when the bike is off and parked. If gas comes out, either the petcock diaphragm is bad OR the hose connected to engine vacuum and the petcock is compromised.

George, are you saying that the vacuum hose is still important when the engine is not running? I'll test the petcock as you stated when I get back on Saturday.

Thanks

Trust me, sometimes a vacumn petcock will malfunction in such manner as it will not shut off. I have experienced this firsthand.

The vacuum hose must not leak air. If it leaks, the diaphragm will not shut off gas. It is critical to have the hose seal with no cracks. It doesn't take much to test... with the bike shut off and the petcock in either the ON or RES position, pull off the gas hose from the petcock. If gas comes out either the hose is leaking air OR the diaphragm is bad; simple as that.

wiredgeorge wrote:

The vacuum hose must not leak air. If it leaks, the diaphragm will not shut off gas. It is critical to have the hose seal with no cracks. It doesn't take much to test... with the bike shut off and the petcock in either the ON or RES position, pull off the gas hose from the petcock. If gas comes out either the hose is leaking air OR the diaphragm is bad; simple as that.

Just to pick your brain a little more. So if I run this test and fuel does come out, then I have an issue with either the petcock or the vacuum hose. To help me diagnose whether the issue is with the petcock or with the vacuum hose would taking the vacuum hose off and putting my finger over the vacuum hole on the petcock prove anything? Meaning, if the issue is in fact the vacuum hose would removing it and plugging the hole on the petcock stop the fuel flow?

Hope my question is clear enough.

If you put your finger of the vacuum fitting on the petcock and it shut off gas in the event that the petcock was pouring gas, that would indicate the hose or hose connection was the issue.

Perfect, thanks for answering that. I can't wait to get home to try this. I'll probably be back with more questions this weekend after I test.