fuel tank return ?

[maxpaso]

Is there supposed to be a fuel return line on my 88 paso? im running 38 mikunis and the only connections on my tank are fuel out and what seems to be a vent line at the very rear of the tank that runs to atmosphere. shayne

[paso750]

yes, there should be an Y connector before the carbs and the return line should go to the rear connection on the tank.


G.

[maxpaso]

That diagram shows two i only have one, if i apply pressure to it,it builds up and when released escapes back from this line. will the fuel pump pressurise the tank? how does it breath (vent)

cheers

[paso750]

I`ve never seen a Paso tank that only has one connection on the rear right. The tank needs the vent exit. The gas cap seals well enough to create an underpressure in the tank if the vent line is closed or clogged. There have been some topics about this issue.
Photos are always welcome.

G.

[maxpaso]

g, a little background on this bike, i purchased it from a friend and it had sat in a container for 6 years ,after recommishining it allways started first press but fouled plugs after aprox 500-700km
which i put down to running rich, after reading through several search results i stumbled across the posted diagram of the tank decal which got me thinking i was over pressurising the carbs ( running rich) bike runs great but after hard runs wants to stall when pulling up, again ,thinking over pressure.will try to post a photo of underside of tank but unable to till monday, got a ride on through the weekend.

cheers shayne

[maxpaso]

G, heres the photo of my tank[img]htpp://s1128.photobucket.com/albums/m482/maxpaso
/[/img]

well that didnt work, first go at posting pictures i,ll have to read the instructions again

[h1a]

this is how your link shold look:
http://i1128.photobucket.com/albums/m48 ... eltank.jpg

While yours look like this:
htpp://s1128.photobucket.com/albums/m482/maxpaso/

[maxpaso]

sorry about the stuff up i,m still trying work this business out. question still remains, if i run an overflow from the feed to this vent/return line will it serve any purpose?


shayne

[paso750]

I`m speechless. I`ve never seen a Paso tank w/o return line.
If you use the breather as a return line you could run into fuel delivery problems due to underpressure that builds up in the tank. I think this would only work if the filler cap would breathe.
In case your fuel pressure is too high there`re several options like using a fuel pressure regulator, swap the electric fuel pump with an underpressure fuel pump or try a return loop as shown below. "7" is a jet that reduces diameter.



G.

[Fraser]

G,

Just add to the confusion, my 750 Paso fuel tank is exactly the same as Maxpaso; no return line.

Cheers,

Fraser.

[ducapaso]

elder pasos have no fuel return line, have a look to the spare parts catalogue to see how they are.
Mikunis and Dells need no fuel pump and no return line to run.

[paso750]

Mikunis and Dells need no fuel pump and no return line to run

I disagree. Don`t know about the Dells but the Mikunis do. The inlet manifolds are long and the carb sits rather high. W/o fuel pump you`ll run out of gas when you still have some left in the tank.
If a return line is required may depend on the fuel pump. With an underpressure fuel pump you probably won`t need one but if you´re using the original Paso fuel pump I think it`s better to have one due to its high pressure.

elder pasos have no fuel return line

How old is old ? Mine is an 86 and it has one. Fraser`s is an 86 also and it doesn`t have one. I guess when Fraser`s and maxpasos tanks were build it was a sunny friday afternoon and the guys at the factory wanted to leave early...

G.

[maxpaso]

the only thing i can think of is that i dont have a charcoal canister so it does,nt need one. im running 38 mikunis,standard paso pump,bike starts instantly when cold runs well pulls hard but after a sustained run,when coming to a stop she splutters and wont come back to idle, couple of good revs ,returns to idle was thinking i might be flooding bowls while float is hanging.
Fraser, what carb/s are you using? do you vent your fuel line?
G, thanks for the pic of that set up. Im thinking to tee back to vent and try to vent my cap, can,t be that hard. just another thing on the paso to work out.

[paso750]

I wonder how venting a filler cap would work. One would need a valve. If you just remove the rubber seal you´ll have fuel spilling over the tank as soon as you put the bike on the side stand.

[Fraser]

Maxpaso,

I have some Mikunis, still have the fuel pump (easier to leave it than remove) and the fuel line is vented.
Cheers,

Fraser.