My '94 Sambar started to leak fuel (shortly after I had cleaned the carb). I traced it back to a line coming out of the Carburetor Purge Canister. The photo shows a top down view of the line after I pulled it out of the right side frame (note the ac condenser in the background). I'm guessing that it is normally supposed to vent gas and not liquid. My question is... would replacing the purge canister solve my problems? Or did I mess something up in the carb? I didn't touch the bowl float level but I suppose its possible that I might have bent it on accident.
Sounds like a sticky float needle causing the bowl to over flow. I usually hit the outside of the needle with some fine grit paper and make sure it moves freely.
Turns out there were two issues: I did bend the float a small amount when reassembling the carb (thanks banzair). The fuel return line (from carb to fuel tank) was swapped with the purge line (from carb to canister). No wonder it was leaking fuel from the canister. I'm guessing the power loss and hesitation when on throttle (why I was cleaning the carb in the first place) was from the carb not getting the fuel vapor & air mixture from the canister. Now I'm having trouble starting when the engine is warm. I think this is caused by my now ruined charcoal canister. I took my truck to a local shop (which specializes in Subaru and had JDM experience from skylines & Cedrics) and they incorrectly reassembled the lines. The strange thing is that it took the problem ~30 miles from barely noticeable to undrivable. I need to make myself a vacuum diagram for this truck and glue it onto the engine cover. Hard lesson learned.
Ok, here’s we go., with a very condensed version of what is happening. The vapor canister contains activated charcoal. The Activated charcoal collects the vapors evaporating from the gas tank, and the float bowl when the truck is off, so they don’t get into the atmosphere. When the truck is on the purge valve opens and pulls air through the canister to evaporate the vapors back into the air stream going though the engine, where they are burned. Early systems were open. My 73 Dodge and 77 Toyota both had an air filter below the charcoal, and would pull air directly from the atmosphere through the canister and into a vacuum port on the carburetor. Later the systems were closed. There is a line from after the air filter to the canister, and then another coming back to vacuum at the carb. There are typically two more lines: one from the float bowl and one from the gas tank to hold the evaporating vapors. My Hijet has an electric valve on top of the float bowl which lets the float bowl line serve as the suction line. When the truck is off the valve connects the hose to the float bowl to catch the fumes which evaporate. When the truck is on the valve moves, and connects to vacuum at the carb, and works as the suction line for the system.
