Hello there,
Can anyone explain to me, the mystery of how the 1000SP (1980 Spada) fuel tank is vented?
Its the same tank as the T3 except the filler cap design is different.
See photos of the Spada filler cap.
Kenny.
From memory I think it vents from gaps in the white bit into a chamber (black)and released onthe other side of the seal through pinholes. Also if mine was anything to go by it just didn’t fit very well
Thanks Temp5655jr for the reply. I’ll need to dismantle it so to verify that its clear. Bike runs ok for frist few miles and then starts to miss. Just need to eliminate another possible root cause.
Hi, just a suggestion. When the tank is part full run the bike with the filler cap loose. This will tell you if that is the problem. The other option would be to disconnect the fuel pipes from the carbs and then open the taps and see if the flow rate decreases over time. If it does, open the cap and see if the flow returns to normal.
Thanks for the reply Phil. I had thought of running the bike with the cap loose but the other idea I hadn’t thought of and sounds very do-able in the garage and should work as you described. So cheers for that one. Everyday is a learning day - right!
I am mystified however as to how did Guzzi design the venting for this tank/cap design. I think Temp5655JR suggestion is likely to be on the money.
Hi Kennyk,
Saw your post re tank venting, … unfortunately I have the same tank cap and wish I hadn’t .
I seem to have the opposite problem, … too much venting!
It would seem that rubber/nitrile ? seal hardens up with age …and allows (esp with a full tank ) fuel to slosh out all over the tank top! (no baffles in the tank I reckon?) … so was wondering if you have ever seen a replacement metal filler cap that would fit without replacing the tank , …or even new soft rubber seals to replace?? … I’ve been looking for ages and the best fix I’ve found is ‘reconditioning’ the hard rubber seal in a solution of Wintergreen oil & alcohol !!
Sorry I’m not helping with your problem, … Methinks it must be something other than a cap vent issue as these horrible plastic caps seem to vent ok through the spindle that holds the retaining clip in place ??
Good luck …
ISCO
Hey @ISCO - welcome to the forum!
Can’t help with all of your questions (because my tanks use a different cap/seal mechanism), but! I can help a wee bit with that seal - they do harden, or split, as you say and (sadly) it seems that none of the regular Guzzi parts places can help with replacement, but eBay can. Not sure quite what your particular seal looks like, but mine was a disc (T3) so this item got me sorted: 2 x Bespoke Size Viton Disc Discs 2mm thick | eBay (and thanks, in turn, to other Guzzi people who set me straight when I asked a similar questio).
Hope this help (o:
My Spada has a similar tank flap. When the plastic flap is closed, the centre piece is lifted off the flat circlip & presumably vents up around the centre plastic pin.
Ahhh…thats must be it. As Temp5y655JR pointed out, it vents thru the cap but the center piece changing position when closed, was the missing link for me. Thank you Don Spada.and hopefully ISCO also got sorted.
Thank you all for your inputs. Its good to talk !!
I never fill mine above the neck that protrudes down into the tank. That is there to prevent excess fuel splashing up onto the underside of the fuel cap.