relistan
Member
Hi all, I've just gotten my car last week ('66 SC with a 2200 motor) and have driven it a few times. It runs absolutely fine when cold, but after the car has heated up for awhile it will start cutting out, especially under load.
I have now established that when this happens, I can see lots of bubbles in the fuel pump. Since the dome is on the inlet side, that points to the line upstream, between the pump and the fuel tank. I fitted a clear filter downstream from the pump, between the pump and the carb so that I could see what was going on. It turns out that in this condition, it is pumping a LOT of air. A lot more than I can see in the dome on the pump. Big bubbles coming up inside the clear filter. The car will usually idle, but if I watch that filter there are times when it is almost entirely filled with air/fuel vapor. It seems like too much for fuel vaporization.
Given that it seems to be sensitive to heat I can only guess that it's vaporization in the fuel line upstream from the fuel pump, or an air leak in the pump. Note that in order to fit the clear filter, I replaced all the hose and fittings between the carb and the pump and there is not an air leak there. The bubbles are clearly visible in the glass dome on the pump. This is a pretty good volume of air or vapor so my guess is it's air introduced by the pump? Is this a common failure mode?
Help appreciated!
Thanks
Karl
I have now established that when this happens, I can see lots of bubbles in the fuel pump. Since the dome is on the inlet side, that points to the line upstream, between the pump and the fuel tank. I fitted a clear filter downstream from the pump, between the pump and the carb so that I could see what was going on. It turns out that in this condition, it is pumping a LOT of air. A lot more than I can see in the dome on the pump. Big bubbles coming up inside the clear filter. The car will usually idle, but if I watch that filter there are times when it is almost entirely filled with air/fuel vapor. It seems like too much for fuel vaporization.
Given that it seems to be sensitive to heat I can only guess that it's vaporization in the fuel line upstream from the fuel pump, or an air leak in the pump. Note that in order to fit the clear filter, I replaced all the hose and fittings between the carb and the pump and there is not an air leak there. The bubbles are clearly visible in the glass dome on the pump. This is a pretty good volume of air or vapor so my guess is it's air introduced by the pump? Is this a common failure mode?
Help appreciated!
Thanks
Karl
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