Sorry to keep spawning a new thread every time this comes up, but I'd like some advice on the carbs. That seems to be where the problem lies.

You all know my fuel economy is terrible. 13-16 mpg, approximately half of what it should be getting. I've investigated the fuel tank, fuel filler neck/cap (NO leaks there even under hard acceleration), fuel hardline, fuel pump, and fuel line to the carbs.

I only lose fuel while running, and it's especially bad on the highway.

There's no smoke out the tailpipe, and the lift-pin test on the carbs indicates that the mix is just fine. Added to all that, I've just replaced the head and *finally* got my valve lash correct. My points and condenser are new along with my cap and rotor. I running a blue bosch coil with magnecore wires and NGK BP6HS plugs. I also have a locking gas cap, so no neighbors with siphons either...

The car idles like a well-oiled sewing machine, starts quickly, no longer diesels on shutdown, and has a nice smooth curve of acceleration.

Yet...
I've driven the car 35 miles and I've burned a 1/4 tank of fuel. This is very consistent with my "usual" poor economy.

I'm not losing fuel in park, I do not seem to be burning it. It *must* be leaking out somewhere, and I suspect that it happens around the lower portion of the carbs. The top fuel reservoir seals and rubber connector hose were replaced and there is NO evidence I'm losing fuel there. I check often.

So... where else on the carb could I be losing fuel if it is not getting burned and it is not getting out at the top of the reservoirs? The jets seems like the only possible culprit. BUT, there are no wet spots under the car at idle, whatever is it must open up (big time) under acceleration, but seal back up when parked.

Do these symptoms strike a cord for anyone?


Thanks as always.