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MG MGB Technical - Fuel pump questions... and clutch too

Ok, we got the motor to crank hard, replaced the High Tension wire and got spark... but when we hooked it up to start it we heard a pop, and lost electricity (jumping it through the old batteries, dont have new ones yet) and we wiggled the cable and got power back, but now when we turn the ignition to on, or crank, the fuel pump doesnt seem to run. I was wondering if it shuts off when the floaters are full or if we lost the fuel pump now, the car SHOULD be starting, it cranks hard, and we have an OK spark. Also, we bled the clutch due to massive air in the lines, filled it, followed proper procedure. The clutch is very firm now and feels right, but it still doesnt seem to engage. We tried starting it in first with the clutch in and it lurches... but the clutch hydrolics feel very firm and there didnt seem to be anymore air in the lines. Any help is appreciated, thanks!
Bryan Corey

Ok, well I just read that the pump doesnt pump when the floaters are full, so if this is true, why isnt it starting? I get spark, crank, and fuel, whats wrong? Am I not choking it properly? The Carb piston is supposed to rest on the carb floor (so to speak) right? like, just be able to fall freely and have the needle go down into the jet? Im not so sure I AM getting fuel into the carbs. I cant find our manual, so I dont know the proper choking procedure. When I had the air filters off, we tried, and the pistons raised and dropped up and down... but I didnt see any fuel being taken in. Could someone point me to the exact choking and starting procedure?
Bryan Corey

Using whatever prcaution are needed, remove the fuel line fom the carb and have an assistant turn the key on while you hold the end of the fuel line into a large container to see if the pump is actually working. If its not then check the fuses to see if you've blown one, it should be the third from the top.

How long as this car sat unused. It could be the clutch is rusted to the plate.
william fox

Starting from cold I think most people use full choke and no throttle, and don't bother pumping the pedal with SUs. If you have HS SUs (float chamber on the side) then look under the carb at the jet while someone pulls the choke, you should see the jets move down (which makes it an 'enrichment device' rather than a 'choke'). Unless the ambient is very warm you may not get it to fire unless the choke is functioning.

As soon as it fires up you should be able to reduce the choke immediately, possibly by about half, but YMMV. If it isn't going to start because of an ignition problem you will flood the engine after an extended bout of cranking, get a strong petrol smell (esp. in a garage) and if you remove a plug it will be wet. Even a short bout of cranking should result in quite a strong petrol smell on a plug when removed, that is one of the ways to check that fuel is getting right through to the cylinders. If it is then check for spark at each plug (remembering that old plugs may spark out of the head but not under compression), plug lead order (1342 *anti*-clockwise) and the timing of the spark (shortly before TDC on the *compression* stroke).
Paul Hunt

This thread was discussed between 01/06/2002 and 03/06/2002

MG MGB Technical index

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