Vacuum in Fuel Tank

[Hugh Jardon]

I am getting a partial vacuum in my fuel tank (1150GS Twin Spark) doesn't appear to be causing a huge problem but I guess it needs sorting

Anyone know where the breather is and how best to unblock ?

 

[Uncle Crumpet]

get a smaller hoover! Breathers run down right side of bike under sidecover.

 

[Dragon Master]

I had this problem on my first 1100 some years ago.

Have a look at the pump mounting plate. On mine, a small metal pipe, with a right-angled bend in it, has a breather pipe connected to it. The metal pipe had corroded internally and become blocked on the bend.

I tried clearing the blockage by inserting the frayed end of an old cable and twisting it, if this is your problem, you could try that. But be careful, I managed to break the pipe on the bend. Luckily the break was behind the blockage, and there was enough left sticking from the back plate for me to connect the rubber pipe to.

But get this sorted, I took my time over it, and only acted when it was too late, after the repeated sucking of a vaccuum in the tank put a deep crease in the left hand side.

 

[Timolgra]

Squirt some wd40 down the tank filler breather and poke an old brake cable or similar down to try and clear it. I tried that and it didn't work

So a quick blast with an air line sorted it out although some may tell you to be careful in case it blows the rubber pipe off........whether they know that for a fact is another matter

 

[Steptoe]

So a quick blast with an air line sorted it out although some may tell you to be careful in case it blows the rubber pipe off........whether they know that for a fact is another matter

Gently blow with an airline.

The pipe can and will blow off internally if the blockage is severe enough and you give airline the full beans.