Thread: Zenith 361V Blocked

Hmm... not really sure, perhaps a vacuum leak that takes the car getting warm before it happens? Something like a warped top on the carbie? That one is fairly common. Check timing, rev the car to make sure it moves with mechanical and vacuum advance, take off the vacuum advance to the dizzy and block it to set the timing and then see if it changes when you put it back on. Unfortunately there are a lot of possibilities despite the fact that it is a very simple engine setup . The coil on one of mine was getting very hot and the car would start and run for ages, but if you then turned it off it would not start again until everything cooled down. Changed the coil and away it went again.

Sorry, not sure if that helps a lot.

TimJ.

An old motor bike trick I use that rarely fails for me to clear blocked carby jets, if you can get the engine started at all is to remove air filter hose from carb, slowly build engine revs up by manipulating the throttle linkage by hand, and when the engine won't rev any faster block the top of the carb with your other hand with the throttle wide open. The engine wants to suck 2.28 litres of something every second revolution, if you block off the air supply it will try to pull it through the jets of the carb. Just before engine stops from overfuelling take your hand off the carb top and repeat procedure until engine runs normally. Speaking of normal. Zenith carburator castings dont get normalised (stress releived) prior to machining during manufacture.What happens is that they get normalised and distort with the repeated heating and cooling of the engine in service, which leads to overfuelling. To restore the carb it should be completely dismantled and all flat surfaces dressed by rubbing them on a sheet of wet and dry paper placed on a smooth flat surface or a sheet of glass. Once done they generally don't distort again.
Wagoo.