Ducati tank sucking...

[Voltaire]

Noticed over the last few months a tendency for the filler cap when opended to suck air in with a loud woosh.
I checked the vent and it seemed ok.
Also from time to time the fuel system would ' spit' and then it would be fine.
Last weekend following a run to a BFTP rally in Hastings and 1300kms I thought I'd see if I could get from Taupo to Auckland on one tank of 15 litres...yep no probs.
Last night I took off the tankbag and to my horror I saw that the tank had imploded on itself.
I scoured the net and it turns out to be a known issue with the SS and Monster range and possiblily others.
The cause is the rubber seal under the filler cap that should guide the air from outside into the tank. As the petrol is used up the space is taken by air.
However in my case the rubber o seal covered the hole and the tank went into vacuum, with the pump just pumping fuel to the injectors. Eventually the vacuum causes the tank to collapse.
I looked at all the options....and went with pressurising the tank via a regulator, mainly because I had a cylinder of nitrogen a regulator and some refrigeration guages.
I drained and removed the tank, sealed up the fuel lines and slowly pressurised the tank to about 10 psi ( less than 1 bar).
It popped out and was way better but still with some dents.

Removing the filler cap revealed a series of tiny grub screw around the inner ring of the filler , these were tricky to remove as there was some corrosion and they were only about 3 mm.
After that I removed the pump and filter.
The inside of the tank was corroded and the bottom rusty and gungy with water/fuel/rust.
There is one tiny pin hole in the bottom.
I need to find someone who can repair the dents, preferably one of those paint less dent jobs....then I'll Por 15 tank seal it, fit a new filter and put it back on.

I was surprised to see the inside of the tank in this state.....but the bike is a jap import and they spend a lot of their life sitting with the air condensing and moisture accumulating in the tank.
Take a look at the pictures, it might be worth shining a tourch into your tank.

[CookMySock]

Sorry, but I had to laugh at your tank pics.

The look on your face would have been priceless.

Steve

[MIXONE]

All I can say is fuck man.I have never seen that happen before.
DB do you laugh at cripples too?Laughing at a fellow biker's misfortune is pretty bad.

[CookMySock]

Laughing at a fellow biker's misfortune is pretty bad.

Thats the sort of thing that gets millions of hits on youtube. Yeah, it's a bitch I know though, but I can't get his shocked face out of my mind.

Steve

[Voltaire]

Well it could be worse, I could be living out my motorcycling existance posting thousands of moronic statements on KB, riding a Hoysong ( whatever they are) and listening to Greensleeves at my place of work.

When I was pressurising the tank today I did think that If I had been you I would have used LPG and found the leak using a lighter.

"I'm a licenced Mr Whippy"
"What Stupid Bastard said"

now go away and play with your flakes and cones.

[CookMySock]

At least its not an ancient piece of scrap like yours, AND mine doesnt have a dented tank!



Steve

[Voltaire]

At least its not an ancient piece of scrap like yours, AND mine doesnt have a dented tank!

Have I stumbled into Pointless Drivell , the natural home of Dangerous Bastard the biggest dickhead on KB?

[Paul in NZ]

Pfft - ALL Moto Guzzi owners KNOW ducatis suck...

[nothingflash]

At least its not an ancient piece of scrap like yours, AND mine doesnt have a dented tank!



Steve

Fuck mate - what a tosser. I've read some pointless shit of yours in the past but that takes the cake.

[Max Headroom]

At least its not an ancient piece of scrap like yours, AND mine doesnt have a dented tank!



Steve

Wow. By what measure is a late model Ducati an ancient piece of scrap? Are you jealous, insecure, or just plain incapable of any form of empathy?

What a miserable, shallow existence you must endure . . .

[SS90]

Is the second picture after you have blown out the dents?

[Motu]

Of course it's not an ancient piece of scrap....maybe just a piece of scrap then.We'll have to blame the fuel injection - it wouldn't happen with gravity feed,the bike would just stop.Car gas tanks seen to have positive pressure...air rushes out when you take the cap off.Obviously they have fitted injection to a carbed bike as an add on.

[Voltaire]

yes, not 100% successsful.....but better.

and for Mr WHIPPY:

....You should have seen the look on my face....it was the the look of the kid who asked for a single cone and got a double cone with a flake boom boom....as in Basil Brush...not using LPG for spraypainting, soda blasting, water blasting or frothing icecream.

[Tank]

At least its not an ancient piece of scrap like yours, AND mine doesnt have a dented tank!

And yet it is still worth more than your hyoshit new.

[bogan]

Of course it's not an ancient piece of scrap....maybe just a piece of scrap then.We'll have to blame the fuel injection - it wouldn't happen with gravity feed,the bike would just stop.Car gas tanks seen to have positive pressure...air rushes out when you take the cap off.Obviously they have fitted injection to a carbed bike as an add on.

with cage tanks i think its cos of the fuel recirculating through the manifold and heating up the tank, and expanding the air. When the car cools down the tank draws in new air through the check valve.

But yeh, that's pretty weird to suck in the tank like that, I suppose the upside is that there won't be the gouges or sharp angles on the dent associated with dropping a bike, so hopefully a lot easier to fix perhaps?