Reinstalling Fuel Tank

Montanarolo Posts : 21 Join date : 2018-06-24

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Hello - Due to some family/health issues with the paint shop that was fixing my tank, it took about 4 months for me to get it back, so my memory has suffered and I now realize I should have taken better photos when removing it. The fuel cap is back on and the fuel pump has been installed, but I’m confused on the hose locations and was hoping for some help. Side note - the canister was removed prior to me purchasing the bike and when I had it serviced after my move, the local shop said some of the hoses had been in the wrong place and they fixed them. So not sure if the shop “fix” messed things up, or if I’m looking at leftover hoses from the the canister removal.

In the photo, hose #1 was connected to the right tank vent with a pinch clamp when I removed the tank. I looked at the hose and it ends about 8 inches down and is not plugged.

Either #2 or #3 were connected to the left vent w/o using a clamp. So I’m wondering if #2 and #3 should be attached to both vents and #1 is useless? Not sure why they would use different hoses for each side of the vent and only clamp one of them.

Sorry for all the questions and thank you in advance.

Grignapoco Posts : 144 Join date : 2019-12-05 Age : 53

3 is the transmission breather. you should trace it down to confirm. leave it there
there should be 2 tubes connected to the fuel tank breather system. they either tie together and exit the bottom of the bike or exit the bottom of the bike separately (it depends how the cannisterectomy was performed)

GRiSO Capo Posts : 398 Join date : 2016-01-25 Age : 66

3 looks like the gearbox breather - Guzzi loop it up over and down through that bracket that holds the battery clamp.

That would make 1 and 2 the cap filler drain and tank breather hoses - but i cannot remember which side is which

GRiSO Capo Posts : 466 Join date : 2016-12-20

LH is the cap filler drain
RH is the tank breather.

On my bike neither connections to the tank had a clamp on them.

Make sure neither hose is kinked once you have the tank on; it's easy to create an issue, with the frame cross member right there.
Yesterday I was fixing my tank breather problems; whoosh of air as the cap was opened, noticeable distortion of the tank. Using a mirror & flashlight found that the hose was kinked just behind the tank barb.

Montanarolo Posts : 21 Join date : 2018-06-24

Thank you both! Got the hose order sorted and the left hose was kinked, so I was able to fix that as well. [You must be registered and logged in to see this image.]

GRiSO Capo Posts : 2822 Join date : 2013-05-29 Age : 62

I like the stripe.

GRiSO Capo Posts : 398 Join date : 2016-01-25 Age : 66

If there was a banjo fitting that could be screwed in to replace the tank breather spigots...

or one of these with the right thread [You must be registered and logged in to see this link.]

Or this may be the one if it is 8mm thread [You must be registered and logged in to see this link.]

Then the hoses would drop vertically in front of that frame tube.

Then tank removal and refitting would be a bit easier
and the hoses would be much less likely to fold and block as you put the tank back on.

Still think Guzzi were talking too many risks dangling the transmission breather near all of the other hoses.

GRiSO Capo Posts : 1085 Join date : 2015-01-04 Age : 60

All true....breather can also dangle into the throttle cable control end & you get very high idle and weird low speed behaviour (don't ask how I know that one).

GRiSO Capo Posts : 1085 Join date : 2015-01-04 Age : 60

& you reminded me of the old adage...IF my aunty had balls, she'd be my uncle.

GRiSO Capo Posts : 398 Join date : 2016-01-25 Age : 66

Well the barb tails coming out of the tank are m7 x 1.00 thread and i cannot find any threaded elbows or banjo's that use the 7mm thread

So back to the standard little struggle to get the two breathers staying both on the barbs and untrapped when re-installing the tank Sad

Grignapoco Posts : 144 Join date : 2019-12-05 Age : 53

I used a combination of new fuel line, brass barbed fittings ( 1 90 & 1 T) and oetiker clamps to route the vent lines so they wouldn't kink or get pinched between the tank & frame.

everything was tested courtesy of a malfunctioning gas station pump and works as it should

GRiSO Capo Posts : 398 Join date : 2016-01-25 Age : 66

Hi Chris
I agree with the idea of placing the drop away from the barbs to increase clearance but i am trying to avoid solutions that join the two pipes as it rains quite a lot here Smile

and I don't want to tempt the breather into sucking back any rain water.

Going to try oetiker clamps and then catching the pipes together in the middle with a cable tie before they drop then running them down by the shock

Grignapoco Posts : 144 Join date : 2019-12-05 Age : 53

sounds like a plan - stay dry!

GRiSO Capo Posts : 398 Join date : 2016-01-25 Age : 66

That worked well
With the pipes running running as a pair i could feel them without looking and keep them free as the tank dropped in.