i have recently converted my mk1 golf gti to twin weber 40 carbs and it has been running ok up until now, however after replacing the engine mounts, the car won't start. there is a strong spark from all of the spark plugs. there is fuel at the carbs and in the float chambers but there is none getting through to the cylinders. what things should i be checking for to fix it? how do i check float levels etc? thanks for any help tom