MG Car Repair: 74 MG carb follow up, jet needle, flow gas

Question
hi Barrie - thx for the link on HIF, however my MGB was a conversion  to HS4 type SU's.

..so on the HS4's is it possible that the jet needle is adjusted wrongly allowing gas to flow? Gas is immediately pooling and pouring from the intake ( but the bowls are not flooded, nor is gas flowing into the vapour hoses.)
      
PW

Answer
Hi Paul.  No, the jet needle is only a metering device.  It should never touch the jet, not even when the engine is switched off.  The fuel level should be below the top of the jet, so fuel only flows when the engine sucks it out of the jet.  

If fuel is pouring from the inlets you have a real problem.  

Have you done ANYTHING else that might explain your symptoms?  For example, I recently diagnosed a problem where the timing chain had been replaced.  The camshaft was timed incorrectly, so instead of sucking fuel, the engine was blowing fuel out of the carburetters.