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MG MGB Technical - starting problem

My 74 chrome bumper b was starting with no problems. It was parked for aprox 3 week and now won't start. The engine cranks but will not start.I tried to jump it wit no sucess. The fuel pump ticks, but I can't tell how much fuel is in the fuel filter.
Any ideas would be appreciated. Can the fuel pump tick but not get fuel out? if so what needs to be done. Any other ideas would be appreciated on getting the car started.

Rick
rick baranyi

What type of fuel pump - SU or other?

Take the fuel hose off the rear carby and put into a 2 litre (2 quart) container. Switch ignition on for about 5 seconds and see how much fuel you have in the container. Flow rate should be around 1 - 2 pints per minute depending on type/model of pump.

If the above is OK then it isn't a fuel delivery problem. Check test ignition system (plugs, points -if fitted, coil, condensor -if fitted, plug leads) for proper operation and settings. If all that is OK, move on to carby settings etc.
J Tait

Fuel filters can be anything from full to empty and have no effect on running. If the pump is chattering then either the tank pickup is above the fuel level (no fuel or hole in pickup pipe) or the inlet non-return valve is stuck open. If it only ticks occasionally that is normal, i.e. carbs fully charged, but could also be the outlet one-way valve stuck closed, pipe to carbs pinched, both float valves stuck shut etc.

Just taking a fuel delivery pipe off a carb immediately after turning *off* the ignition should be enough to confirm the pump and pipes by giving a spurt of fuel. Still leaves float valves, which being HIFs (I assume) are a pain. If you can fit a tube to each carb overflow port, remove the air cleaners and lift the piston with a finger by blowing in the tube you *should* see fuel bubbling up through the jet if there is fuel in the carbs. If not, try blowing hard in the fuel inlet ports in an attempt to free the float valve.

If you have fuel coming out of the jets connect a timing light to the coil lead and each plug lead in turn and watch for flashes as you crank. When on 1 or 4 point at the crank pulley to check timing is about 10 degrees BTDC.

If no flashing on the coil lead check for 12v on the coil +ve, which assuming chrome bumper should only drop to about 10v during cranking. The coil -ve should switch between battery voltage and 0v as the points open and close. On an analogue meter you can see this as averaging about 5 or 6v during cranking.
Paul Hunt 2010

This thread was discussed on 27/05/2010

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