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MG MGB Technical - No Gas in Carbs

I just bought a '73 MGB. It has HIF4 carbs. The air rail and pump have been removed and all plumbing related to that seems to be done correctly. I have gas at the carbs but it will not start on its own. If its "primed" with gas or starting fluid it fires right up, then dies out when that burned up. Looking for ideas for where to begin looking.
william fox

If it has been sitting for some time, fuel evaporation leaves gum deposits, right where the fuel level is for idle/low speed. That is on the carb needles and in the jets. Since the area for fuel feed is on the order of 1-2 thou, it gets no fuel. Lift the pistons and squirt some "fuel injection system cleaner" into the jets and let sit for a while. Then crank it over and choke it to death by blocking the carb intake while cranking. That makes very high vacuum and sucks fuel and water out of the jet. Repeat if necessary. If you don't get gas then, the float valves may also be gummed up; either squirt cleaner in the inlets or remove the tops and clean the float valves. Put the rest of the cleaner in the tank with fresh fuel, at about double the specified dose. 100 miles on the road - good as new!

FRM
FR Millmore

William,
You're going to have to remove the carbs to get to the float chambers. The cap to the float chamber is at the bottom of the HIF. It would be a good time to clean and check out the carb anyway.
Joe G.
J. E. Guthrie

But try Fletcher's method first, because if it works, you won't need to disassemble the carbs! Squirting cleaner into the jets, and into the fuel inlet ports has a good chance of success. After that, the detergents in the fuel will take over.

But... never store a British car without adding SeaFoam to the gas tank and driving a few miles first.

If you're queasy about rebuilding your carbs, let me know.

warmly,
Dave

dave at dbraun99 dot com
Dave Braun

I just got the car. Supposedly the carbs have been rebuilt, new gas tank, fresh fuel. I figured the carbs would have the come off the opened up.
william fox

This thread was discussed between 16/05/2011 and 17/05/2011

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