My 1976 450 Sl stop starting , The plugs are in good shape and they are getting sparks, but they smell gas. Car does not start , I try to adjust the fuel distributor by turn it clock wise 1/8 at a time to adjust mixing fuel and air , And I have changed the distributor ... still car does not start. I am afraid it could be the timing belt need adjustment . It seems to me that the plugs are not getting the sparks on time when the injectors are spitting the fuel. So , How can I adjust the timing belt to make the sparks work on time with the injectors.Thanks Sam