2012 Stelvio NTX tank vent

[River Rat]

I have a blocked tank vent on my 2012 that is causing a few running issues, pulled the hose from the nipple just now and tested with this......



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........ no flow in either direction (the drain on the LHS is clear), has anyone experienced this problem and if so how was the blockage cleared?
thanks, John

BTW, here in Oz we have no canister

[Kiwi_Roy]

Is it anything like the moat drain on the EV tanks (tiny spiral pipe from the filler out the bottom of tank)
The EV tanks rust up because with the drain blocked water has nowhere to go but in the tank where it turns to rust and plugs the filter.
They can be drilled out using a length of inner cable in a drill, takes several hours to do one using progressively longer cable with some light oil and and compressed air.

I think it was Patrick who gave me that valuable tip.

Please post a picture of the opening/s you can see.

[Wayne Orwig]

Have you tried it with the gas cap removed? I think there is some valving inside the cap.

[pete roper]

I was wondering about that but I'm so jet lagged I couldn't remember the vent location. If air won't pass through the vent from the outside of the tank though that indicates a blockage there.

[Daniel Kalal]

I am watching this thread with interest.  I've often rented Stelvios from Agostini.  I'd say about a third of them (perhaps less) will have pooled water around the filler neck after a heavy night rain--open the cap and there's standing water around the periphery including over the drain hole.  No drain at all.  The tank seems to still vent properly.  I've thought about buying a sink stopper (just a circle of rubber) from Ace hardware and laying that over the cap when the bike is parked outside.

[River Rat]

Have you tried it with the gas cap removed? I think there is some valving inside the cap.

Yep, drain on LHS works perfectly, the parts diagram shows an O ring under the nipple that screws into the tank and I am wondering if it has been over tightened. I will take the nipple out of the tank tonight after work and have a look

[River Rat]

Is it anything like the moat drain on the EV tanks (tiny spiral pipe from the filler out the bottom of tank)

Please post a picture of the opening/s you can see.

No,it's a plastic tank so no corrosion, will post some pics tonight

[River Rat]

.....so, pulled the nipple from the tank and ran a wire up the vent, no apparent blockage in either nipple or tube







I then pulled the fuel cap off, there is a check valve in there but when I disassembled it there was no apparent blockage.  With the cap off I could blow air in both directions through the internal tube in the tank











Anyhow I reckon I have found the culprit, the hole in the plastic that should allow the passage of air in and out of the tank (small hole next to the hole with the threaded insert, the one that the metal ball sits above in the vent) is blind, does not pass any air at all.  I think that Luigi has struck again, and that I should just drill it through but I'm a bit reluctant to do so without knowing for sure, your thoughts Pete?




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Update edit:  since I posted this curiosity (driven by logic) got the better of me, so grabbed my drill and the smallest bit I had and drilled through into the tank, vent now works perfectly as it should............

[Kiwi_Roy]

Luigi, in charge of adding character.

[pete roper]

No, Luigi was off hiding the grease pot. This one is down to Marco!

[River Rat]

 

[Wayne Orwig]

Oh no. Did you really drill that?


Now it is trashed. I'll give you $500 for it. If you pay shipping.