I had occasional intermittent H and L side lean symptoms. I narrowed it down to either a leaking main nozzle check valve that would let air in at idle, and show itself both at idle and WOT as it’s sucked the leaked air, or a restriction. However it was intermittent, didn’t happen every time. Maybe once during a tank.
I sprayed fluid through the main nozzle and it came through just fine.
Tested the main nozzle valve whilst it was in place in the carb and it leaked.
I decided to take it out of the carby to check the nozzle was indeed leaking and it wasn’t leaking past my hose as I pressed it against the drilling . Well look what I found! These pesky buggers, when agitated by quick fuel demand could very well be the culprits for occasional lean H symptoms !!! How they got in there I’m not sure, I can only presume upon installation of the main nozzle scraping off casting flash from the factory? It wasn’t me, the walls of the drilling for the nozzle were un-scratched and they aren’t magnetic so it wouldn’t be from the punch and it wouldn’t have made it through the mesh screen or the main drilling in the metering floor.
Anyway, the nozzle was leaking too just a bit which would explain the L symptoms too. Used a good spray of carby cleaner through it and it works perfectly now, it must have been either dry tacky fuel or quite possibly a tiny shard of metal! Its all clean and working as it should - I’ll re test it tomorrow
I sprayed fluid through the main nozzle and it came through just fine.
Tested the main nozzle valve whilst it was in place in the carb and it leaked.
I decided to take it out of the carby to check the nozzle was indeed leaking and it wasn’t leaking past my hose as I pressed it against the drilling . Well look what I found! These pesky buggers, when agitated by quick fuel demand could very well be the culprits for occasional lean H symptoms !!! How they got in there I’m not sure, I can only presume upon installation of the main nozzle scraping off casting flash from the factory? It wasn’t me, the walls of the drilling for the nozzle were un-scratched and they aren’t magnetic so it wouldn’t be from the punch and it wouldn’t have made it through the mesh screen or the main drilling in the metering floor.
Anyway, the nozzle was leaking too just a bit which would explain the L symptoms too. Used a good spray of carby cleaner through it and it works perfectly now, it must have been either dry tacky fuel or quite possibly a tiny shard of metal! Its all clean and working as it should - I’ll re test it tomorrow
