Hello,
I know that black sooty spark plugs means you have a rich condition but I need some direction as to what may be causing that and how to fix.
I have just put in a new carb (quickfuel ss 680 as recommended by engine builder shop as my previous one was way too small for the engine) and the truck was running fine until I started to try to fine tune it. I obviously messed something up so I need some help moving forward.
I followed the instructions provided to me by the shop I bought the quickfuel from to set it up. (note that timing continues to be locked in and verified with a good gun at initial 18 degrees with mechanical advance stop at 36; vacuum is disconnected for now)
- Set idle transfer slot on primary to 0.035, secondary is closed (when running it had to up the trottle a little, 1 turn, to keep it running as the idle was too low so transfer slot will now be open more)
- Set accelerator spring to just be touching the pump arm
- set idle mixture (4 corner carb) to be 1 turn out at primaries and 3/4 on secondaries as a start
- float is set to middle of sight window as noted in the quickfuel manual where it should. (and I taked with quickfuel and they verified that is where it should be).
So what is happening:
- when I start the truck is it runs fine (idles at 1000) for about 10 seconds and then stalls; trying to keep it going is a losing battle as eventually it will stall. I even took it up to 3000 rpm but then I started hearing backfiring and then it stalled.
I'm assuming too much fuel is being delivered into the carb but not sure how to resolve? I was thinking about dialing down the idle mixture screws on the primary to 1/2 turn but right now I have all plugs out and I'm cleaning them.
Thanks for any help. :thumbup:
I know that black sooty spark plugs means you have a rich condition but I need some direction as to what may be causing that and how to fix.
I have just put in a new carb (quickfuel ss 680 as recommended by engine builder shop as my previous one was way too small for the engine) and the truck was running fine until I started to try to fine tune it. I obviously messed something up so I need some help moving forward.
I followed the instructions provided to me by the shop I bought the quickfuel from to set it up. (note that timing continues to be locked in and verified with a good gun at initial 18 degrees with mechanical advance stop at 36; vacuum is disconnected for now)
- Set idle transfer slot on primary to 0.035, secondary is closed (when running it had to up the trottle a little, 1 turn, to keep it running as the idle was too low so transfer slot will now be open more)
- Set accelerator spring to just be touching the pump arm
- set idle mixture (4 corner carb) to be 1 turn out at primaries and 3/4 on secondaries as a start
- float is set to middle of sight window as noted in the quickfuel manual where it should. (and I taked with quickfuel and they verified that is where it should be).
So what is happening:
- when I start the truck is it runs fine (idles at 1000) for about 10 seconds and then stalls; trying to keep it going is a losing battle as eventually it will stall. I even took it up to 3000 rpm but then I started hearing backfiring and then it stalled.
I'm assuming too much fuel is being delivered into the carb but not sure how to resolve? I was thinking about dialing down the idle mixture screws on the primary to 1/2 turn but right now I have all plugs out and I'm cleaning them.
Thanks for any help. :thumbup: