carbs vent hoses

[Anonymous]

i have a 83'gs1100gk and in the process of rebuilding them .when got this bike it was not running and the carbs were half way torn down,ihave four lines from the carbs ,ifound the fuel line and the reserve but the bike will not start the other two i think are vent hses or vacume hoses i don't know and the book does not tell me whare they go are the other two vac. hoses or chould they be pluged?it does show them in the book not pluged, but is there a tee that go's on them to connect to the petcock or what :x . if you know whare they go it would really help me out.


thanks
craig

[SqDancerLynn1]

First on the engine side of the # 2 carb is a vacuum fitting for the fuel valve vacuum supply on the Tank. Between the #1 & 2 and between the #3 & 4 carbs are vent fittings, attach hose, it usually goes up and over the air box and back down by the center stand. Between the # 2 & 3 carbs is the fuel inlet which is connected to the fuel tank

[Jay B]

Yep thats they way both sets of my carbs are.

[focus frenzy]

the vent line T's should be pointed down with the hoses going straight down behind the engine.
with the vent lines pointed down, If the petcock sticks open and a float needle stick as the fuel level rises the fuel will drain out the vent line before it can reach the carburator venturi, preventing fuel from intering the crank case and contaminating the oil.

[moto_dan]

the vent line T's should be pointed down with the hoses going straight down behind the engine.
with the vent lines pointed down, If the petcock sticks open and a float needle stick as the fuel level rises the fuel will drain out the vent line before it can reach the carburator venturi, preventing fuel from intering the crank case and contaminating the oil.

Are you sure? I don't think the vent tubes on CV carbs peform the same function as the overflow tubes on VM type carbs. The Factory Service manuals that I have show the routing of these tubes to remain above the carbs.

[SqDancerLynn1]

the vent line T's should be pointed down with the hoses going straight down behind the engine.
with the vent lines pointed down, If the petcock sticks open and a float needle stick as the fuel level rises the fuel will drain out the vent line before it can reach the carburator venturi, preventing fuel from intering the crank case and contaminating the oil.

I agree with your reasoning on vent tubes, We have to make sure about which carbs we are talking about . Older style VM slide type have a vent and also a seperate fuel overflow on the bottom of the fuel bowl. BS carbs vent and overflow are the same connection