I was just wondering in general. I have a 1978 Holden Kingswood with a straight 6 cylinder engine (234,000 km), powered by a single barrel Stromberg BX carburetor (from factory). The car has a charcoal canister with one line going to a nipple on the carburetor bowl, another going to the fuel tank and then a purge line. I was wondering if a function of the charcoal canister also prevents vapour lock, or should I possibly install a 3 nipple fuel filter to prevent this?
I ask because I suspect vapor lock to be the cause behind a certain issue. I have a 3 speed TH180 automatic transmission and sometimes when I accelerate from a stand-still very quickly (to take a risky gap in traffic sort of quickly), the car jerks/shakes rapidly and like mad whilst taking off but the rest of the time? Shifts gears beautifully smoothly. The transmission has recently had an overhaul so I don't think it would be that.
If you could answer both questions, I'd be most appreciative!
The charcoal canister's job isn't to prevent vapor lock, it's to aborb gasoline fumes that would otherwise escape to the atmosphere from the fuel tank and carb bowl. Those fumes are then purged from the canister when you run the engine. I have the same setup on my '71 Ambassador, very common on 1970s vehicles. With a 3-nipple fuel filter you would need a return line to the gas tank. On a carbureted vehicle this would be done to keep gasoline flowing at all times to prevent vapor lock. (The 1980s-vintage AMC Eagles I used to own were set up like that.)
Vapor lock typically takes place under extremely hot underhood conditions. The problem you are experiencing sounds more like a vacuum leak, carb problem, or ignition problem.
