I am impressed with the mileage all of you seem to be getting. Since new, I have not been able to get more than 17 mpg on premium. But there was one occasion.
In the process of moving West of Philadelphia during the winter of 1970, I had an occasion to drive up to NE Penn., then to NYC, and finely back to Philly. Cold and snowy, the trip was no pleasure and, since almost all was Turnpike-style high speed driving, I had little reason for stopping.
Somewhere along the trip the car started to balk down after stopping, especially in the city, and occasionally required a little clutch work to get moving. However, since it still could exceed 80 mph, and the weather had deteriorated to sleet, I had no intention of pulling over and investigate unless absolutely necessary.
While cursing at 60 mph on my home trip, I had a flash … I hadn’t stopped for gas and the trip odometer was registering about 350 miles! Although I had a full tank when beginning the trip, my gas gauge was still registering over a quarter of a tank? Anxious and questioning the gas gauge reading, I pulling into the next station and refilled the tank. Startled at the amount of fuel still in the tank, I did a rough calculation to find I had gotten more then 40 mpg. Totally confused at this result, I entertained myself at the cause and possibilities for the rest of the trip.
At home, the next 3 days were spent with a friendly Master Mechanic, identifying my (questionably) good fortune. A cursory review of the fuel system showed no obvious problems but dismantling the rear carburetor disclosed something I had not experienced before or since.
It turned out there were 2 issues that, in coincidental combination, caused the issue/benefit. First, the rear carburetor pin had loosened and vibration would cause it to fall from the piston and block the fuel supply. This condition combined with a lack of damper oil to allow the piston to drop with sufficient force to occasionally reseat the pin when stopped and, for a brief period, allow for normal start-up operation.
Unlike most other engines, the Healey 6 is nicely balanced into two 3 cylinder engines and never showed much displeasure idling on 3 cylinders. This balanced condition was one condition that initially directed us to other possibilities before centering on the carburetion. Over the years, I occasionally thought of causing this condition purposely but, as the Healey passed from everyday to occasional use, the thought passed.
All the best,
Ray (64BJ8P1)