Triumph Repair: poor running of gt6, flame trap, vent system

Question
Jim, first, please excuse my spelling

I have a 1970 GT6 MK2 I bought used, I have replace plugs, plug wires, points, condenser, cap.rotor, fuel pump, coil, air filters,fuel filter, emission valve. I have rebuilt the carbs and set the float adj. I have set the timing to the book specs. The car runs very good for the first 6 to 10 blocks, then seems to be starving for gas, I have to pull over pull the choke and limp home feathering the clutch and gas.

When it dies, if I pull the choke full the car will idle, but as soon as I try to give it any gas it just dies, this happens consistenly.

What is not connected is the small gas over flow tank located in the back of the car next to the gas tank with the tube running up to the charcol filter in the engine compartment, do you think this has anything to do with my problem? Any suggestions as to what I might look for or try, I am at a loss

Mike

Answer
Mike,

Yes, it sounds like the car is starving for gas.  When you did all the other work did you make sure the fuel lines were clean and clear?  The fuel lines from the tank to the engine are mostly steel and prone to rusting inside.

The "overflow" tank I think you're referring to is an expansion chamber/flame trap for the vent system.  If you're not venting the tank properly it is possible that you could be forming a vacuum in the tank... at least enough to limit fuel flow to the fuel pump.  

A quick test to see if that's the problem would be to start the car with the fuel cap open (but maybe taped almost "in place" to prevent much fuel from leaking) and see if the symptoms occur.


Cheers,

Jim