> Okay, look at your canister. It's got three tubes in the top and one
> tube in the bottom, sticking out the side. On top it's got one 1/2"
> hose in the middle that goes to the valve cover, right? That's the
> OUTPUT hose, something that had escaped me for years. That drives the
> whole engine-as-PCV-system, per the manual. The other two itty bitty
> hoses (both, um, 1/ 4" I think) are vapor hoses for the fuel system.
> One of them runs from the carbs to the canister; the other should
> disappear back into the depths of the chassis.
>
Gotcha
> The bottom hose is the INPUT to the canister. It draws air through
> a hose that's supposed to go down to the bottom of the engine compartment
> so that fresh air goes past it. Pressure from the float vents seems to
> drive this whole thing, but I can't determine that for certain.
OK, I need to put a new length of tube on this..at the mo its cut of
at the canister.
snip...snip
> > I am assuming that this is where the tube from the air pump went too.
>
> No, that went into the gulp valve.
>
> Ah! Do you *have* a gulp valve? That's a potential big vacuum leak,
> one that could be causing all sorts of rough-driving problems.
Ha ha....no gulp valve...its is missing the air injection rail..
but the holes are all plugged up.
>
> The air pump has two outputs, one of which goes to the air injection
> rail into the head, the other of which goes to the gulp valve. The
> gulp valve has two 1/2" hoses -- one in from the air pump, one to the
> manifold -- and one teeny (I think it's 1/8") hose that acts as a signal.
> When you lift off the throttle, the gulp valve opens and lets air come
> into the intake manifold (after being pumped and filtered by the air
> pump).
So what happens when you have no gulp valve??
Thanks again
Marcus
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