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MG MGB Technical - Won't start, suggestions please!

This is what I've got:

- 10 degrees BTDC, with #1 pressurizing
- set distributor to test light just going on by turning distributor clockwise
- 12 Volt at coil
- assume wire at 2 o'clock viewed facing the engine from the passenger fender is #1 plug
- blue spark on plugs
- 120+ compression
- Weber carb
- plugs wet when removed

The symptoms are only ocasional "coughing", not close to starting. Suspected 180 out of sync on timing, but I've re-checked several times.

I thought it was the carb dumping gas and flooding when I removed the carb and found a pool of fuel in the manifold. Changed to another Weber but results are the same.

Any suggestions are appreciated.
Brian Denis

A clarification, good compression on all cylinders & blue spark on all plugs.
Brian Denis

Did you remove the distributor cap and check that the rotor is pointing to the number one plug wire? If you did I suggest you remove the valve cover and physically check that both valves on number one cylinder are loose indicating you are on or near TDC of the compression stroke. If all that checks it should run. Good luck, Clifton
Clifton Gordon

Thanks Clifton, I was thumbing through Haynes & Chilton's looking for a light to go on... and I came across a diagram which shows that the rotor is actually passed (counterclockwise movement) the #1 plug wire when timed. So I think I'm off one postion on each wire.... 1>3, 2>4.

Interesting, lots of info on how to time, but not on how to determine which post goes to #1. I was expecting it'd be the next one to the left. I'll give it another go tomorrow.
Brian Denis

The leading edge of the rotor should be at the #1 plug terminal when timing. As the mech advance comes in, the rotor will be further around when the cam opens the points. The rotor must still direct the spark to the correct terminal.
FR Millmore

Brian,

I had the same problem when I replaced my coil on my midget, did you do the same. I came to find out that their was too much juice going to my dizzy. If you have a full 12V than it tends to jump the gap on your points creating a premature spark making you believe that the timing is way off. Also it will eventually melt your points. Took me nearly six months to figure this out. I picked up a ballast resistor to drop the voltage and it worked fine, ran like a charm. I used a 1.2 ohm but you could get away with a .8 ohm They are around $7.00 at the shop. I am not sure of the year of your car but thought I should mention.

Neil
Neil

This thread was discussed between 25/04/2004 and 27/04/2004

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