SU Carhorators

[smilinstevo]

I have a 1971 MG Midget and I have rebuilt both carbs completly and now when i start it, the car will go to a very high rev and i cant get it to go down plus if i give it gas it will choke out and die. Plus it is pouring gas into the oil pan so every time I try to adjust the carbs I have to change the oil. The enging is 12755 cc and the carbs are the original SU's.
I have had the head reconditioned, new plugs, new plug wires, new points, new rotor, new distributor cap, new coil. I am positive that the poit gap, plug gap are exact and the valves are properly adjusted and the timing as well.

[TWR]

Hi, on the top of the carb there is a screw cap, undo that & draw out slowly, add some oil into the chamber & try, regards setting the twins up there are a right Basd. f you have tried that, take off the body of the carb & check the needle valve these have been known to be bent.

[hughjass]

this can only be a carburettor problem,when you say "rebuilt both carbs", have you replaced the needles or made any alterations? have you put the return spring back underneath the carbs? or tried to adjust the tickover speed at the screws to the side of the carbs?

[R1Geezer]

well you've rebuilt something! But you've obviously donalded the carbs mate!

[Brooksy]

Having spent 25 years playing with twin SUs, I suspect you may have incorrectly replaced one of the linkage bars between them. Othewise the needles may be set too high or low in the pistons. Try & get hold of a Haynes manual, local libraries often have them.

[leighb]

Try going onto the MG forum site, the American one, those guys are so helpful and quick to reply, They are better than any Haynes manual. I use it all the time.