Potential Fuelling Issue

[HC Fairley]

Help please. 1256 OHV with 150CD Stromberg. Car was running fine when it was garaged in October. A little over a month ago I started it only to discover the O-ring in the carb had perished. New ones from David Maxwell were promptly ordered and fitted. I did have the adjuster out of the carb to fit these. Counted the threads on the adjuster and screwed it back into the same position as before. Car started fine, I drove down the street to get petrol, about 4 miles, car drove the very best. Stopped to fill up and the car refused to start again, just wound over. I let it sit for 10 minutes and tried again, this time it started but wouldn't take revs and idled very roughly at maybe 4 or 500 rpm very rough and splutter. Eventually got the car home, messed with the adjuster and thought it was sorted but the problem persists. Car will start from cold on the button but refuses to start after being ran for even 30 seconds or a minute. If I keep it running though it will drive anywhere hassle free.

[1972nail]

Sounds like you have a rich mixture, try winding the mixture screw in a half turn at a time. The ideal starting place for the screw is about 2 1/4 turns from the fully in position.

[HC Fairley]

That was the first thing I tried but I will give it another go