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TR2/3/3A TR3 - Gas odor and poor mileage


Jedi Trainee
Hi all,

I have an ongoing problem with my TR3 with gas mileage below 20 mpg. Timing, ignition, and mixture are right on. I have replaced all the fuel lines and fuel pump, there are no visible fuel leaks. I replaced the carb needle valves with viton-tipped ones and I believe that I got them adjusted OK (No visible overflowing). The car runs great, just gets poor mileage. Is it posible that the carbs are overflowing just enough so that the car runs OK but is overflowing gas?

Any and all advice welcome! Thanks, Tim

Don Elliott

Obi Wan
Check the fitting at the bottom of the gas tank. Also all the other places, like the inlet and outlet at the fuel pump. If you have the shut-off valve still installed, it might need attention.


Luke Skywalker
Country flag
Pull the interior back wall or check thru the trunk too as the gas tank cap is attached via a rubber hose with clamps, they come loose and fuel can be splashed up and leak out onto the tank.


Great Pumpkin - R.I.P
One place I had trouble was the tank vent tube, which runs from a banjo fitting on top of the tank (RHS as I recall) through the floor and under the car. On hard turns and a nearly full tank of gas, it was slopping out the tube and onto the ground.

Since at least my car also had a vent in the cap, I just plugged the tube on the tank.

Then again, I only average about 20 mpg anyway with mixed highway/city driving on "reformulated" fuel. The 30 mpg mentioned in the books was with smaller carbs, smaller liners, "real" petrol, and most importantly, Imperial gallons (which are some 20% larger than US gallons).

Deleted member 451

I'm in the same range as Randall. I get 19-20 around town and not much more on the highway. The aerodynamic shape of these cars is very similar to a brick so don't expect much. If you read close those MPH tests from the factory were done with the windscreen off, a metal cockpit cover and wheel fairings. At the time they were built gas was still about 30¢ a gallon, so gas mileage was not a big concern.


Luke Skywalker
Country flag
Hey, I feel good now as I'm getting 22 mpg. Seems much higher at hwy speeds though but haven't checked that.
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