QuestionQUESTION: This Midget is a California car I bought 4 months ago and had shipped to Philadelphia. It ran fine then the mechanical fuel pump apparently stopped pumping gasoline. I called for a tow truck who showed up with a gallon of gas. I had just filled the tank and only driven about 35-40 miles. After adding the gasoline, the car fired right up. I drove home and, assuming I may have a faulty fuel pump, I ordered a new mechanical one. I replaced the fuel pump but the same thing happened. So, I fitted an electronic fuel pump and fuel filter. Again, the same results: driven without issue for about 40 miles, then apparently starving for gas.
I assumed that there may be some residue or other in the gas tank, so I ordered a new tank. I installed the tank last week and, again, experienced the same problem, the electronic fuel pump clanging loudly as no gasoline was being pumped. I checked the tank and could easily see that it contained more than 2/3's capacity of fuel.
The car is fitted with the charcoal emissions cannister required for all California cars of its vintage to facilitate fuel evaporation control. Is it possible I am not getting proper venting of the fuel system? Is there a vacuum there caused by it being unable to breathe? I have a non-vented gas cap, by the way, as I understand that the evaporation system is supposed to be closed.
tony
ANSWER: Hi Tony,
A stopped up vent system is a good possibility. The simple test is to drive the car until it quits and loosen the gas cap quickly and note if you hear a hiss. Even if you don't restart the car with the cap loose and see if you can drive the car past the 40 mile range. If you can you need to replace the charcoal canister and blow out all of the vent lines and be sure to disconnect the vent line from the carburetor to the canister for an additional test because with a stopped up canister the engine will stop with no venting of the carburetor float chamber also. If loosening the gas cap you still have an engine quit remove the vent line from the carburetor to the canister.
Howard
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QUESTION: Howard,
If I am unable to replace the charcoal cannister (no one seems to have it), should I disconnect the vent line from the cannister to the carburetor, how can I bypass this venting system? Would this require drilling a hole, for example, in the gas cap? I have a 1975 Midget that does not have this set up, and I am not experiencing any sort of problem -- well, any sort of fuel evaporation problem, that is.
tony
AnswerTony, I can not advise you to remove any emission control item off of your car. But for a test you should remove the vent pipe off of the canister that goes to the tank and open the gas cap and force air into the hose and listen in the tank to see that the tank vent hose it open. Then put the cap on and run the car to see if it quits. Run the same test on the vent hose to the float chamber.
Howard
