Yeah if I wind in the pilot screws I get major carb backfiring (even on the PJ70's) and it's hard to keep the engine running unless I'm throttling it. On the 60 pilot jets I had to screw the pilot screws out almost 4 turns to get a decent idle. When I went to 70 I they're around 2 1/2 to 3 turns out and the engine runs smoother on idle when around this range of pilot screw turns.
Manuals insist 2 turns. So I assume the fewer screws (i should say turns) the bigger the feed from the jets.
When I put the big pilots in (unknown size because of the #OOPS# drill bit) but maybe .9mm I got lots of backfires- like exhaust backfires.
When I took the carbs off today I gave them a throttle on their own and they squirted from the nozzles just fine but it did look like a lot (not that I know what to look for). I'm confident that upping the delivery from the accelerator pump has improved the running of the engine but of course I flipped the back to front inner venturi as well so perhaps there's a variable that I should have changed separately.
Posted on: 2010/6/15 9:35
Edited by clyons8 on 2010/6/15 20:22:46 Edited by clyons8 on 2010/6/15 20:23:09
Transfer
