Misfire

[kevin the chicken]

Is the shaft worn in the distributor causing movement between rotor arm and pickup in cap

[dandan62]

Its almost new and there is no play. Thanks for the ideas guys. Keep em coming! Cant get it at it today. Another thought is an air leak in the inlet for that cylinder. Will inspect tomorrow.

Yes tried the rotating dizzy thing. Still no 4

[Longboarder]

Still thinking about the apparently poor spark. You have the right coil for the accuspark dizzy. Are both getting good clean 12v supply. Might be an idea to confirm this by rigging temporary flying leads, one direct from battery positive to the + terminal on the coil and the second to the + on the accuspark accuspark. This is to cut out any imperfect wiring in the harness. Then start her up and run as normal. Note, you may not be able to switch off without pulling the + lead off the coil. If the misfire is still there after a decent test then you know your car engine loom is OK.

[dandan62]

Will add that to the list of things to try. Its getting shorter. Slightly afraid of frying the accuspark unit. Just checked all sparks. They all look the same. Did another less rushed compression check. That cylinder has always been about 10% above the others at about 180. Seems good but is there a clue there? Baffled

[dandan62]

Sorted 

My lovely son replaced the carb and manifold last year. Bolts nearest no 4 both loose so and air leak! Phew. He ows me a beer. Suppose i should have checked!