Okay gearheads, let's see who is thinking today

[oh2fly]

1972 2002 shows up yesterday. Has a 32/36 Weber on it. Complaint is when he fills the gas tank, the car runs like crap for a day or 2. He says it is like the choke is stuck on. After a few days, all is normal. What is wrong with the car?

[JohnN]

(nt)

[oh2fly]

(nt)

[JohnN]

(nt)

[Zenon]

Yeah, maybe what John said? Guy fills up with cool fuel from underground tank, maybe the fuel expands as it warms up a bit and then excess pressure caused by plugged vent forces the fuel past the needle valve, flooding the carb?

I would also think there might be fuel starvation if the fuel level drops a lot and a vacuum forms in the tank and fights the pump.

Maybe the return line is hooked up wrong and allows fuel to slosh into the carb? Or the tank vent line is connected to a manifold or carb vacuum port and is sucking in liquid fuel as it sloshes up the filler neck? I'd definitely be having a look at the fuel supply hoses and vent. I have seen some nutty stuff.

Or it could be a red herring? Ask him if the car runs way better after a wash, too. ;-)

regards,

Zenon

[Zenon]

How about... Vent is not plugged but the return line is hooked to a vacuum port?

(edited to add: oops, just realized '72s probably don't have return lines)

regards,

Zenon

[oh2fly]

Or the tank vent line is connected to a manifold or carb vacuum port and is sucking in liquid fuel as it sloshes up the filler neck? I'd definitely be having a look at the fuel supply hoses and vent. I have seen some nutty stuff.

Great guess. The vent hose in the engine compartment was connected to the intake port just below the carb and was sucking lots of gas right into the manifold. The big surprise in the trunk was the gray canister was full of gas. Can you say BOMB? As the gas level in the tank dropped, engine vacuum couldn't pick up any more and the car ran normally.

[Zenon]

So, uhh, what do I get? ;-)

That is scary. I guess luckily the port is small enough to sort-of meter the fuel and prevent hydro-locking the engine. Crazy.

regards,

Zenon

[_z_]

(nt)

[Jaycen_PNW2002]

(nt)