Hi all you BBD gurus!
My 273 2bbl (BBD 4116SA CAP) smells like it is running excessively rich.
Forgot to mention I'm at 5000 feet now.
I rebuilt the carb 1 year ago, I have put 1000 miles on it since. Drivability and acceleration are normal, idles OK, No stumbiling or bogging down. I may have done something wrong in the rebuild but I have successfully rebuilt carbs for years so who knows.
The carb was originally jetted for sea level with the "Standard" jets and after sitting for 4 years and with old gas in the tank I had the car smogged. At that time it passed and all the values were relatively low.
A few weeks later I rebuilt the carb and installed a set of "2 step lean" jets 120-297S, I smogged it this year, still passed, but the values were significantly higher, HC went from 379 to 1358 at 2500 RPM. CO% went from 0.57 to 3.02 at idle.
Just found some info that says too lean will result in a raised HC level (lean misfire)
I was going to see if going back to the sea level (standard) jets would fix the issue but the OE jets are trashed.
Bottom line is I could use a set of 120-310S jets if anyone has some. Or what the ID of the jet is and I can drill out my 310s
The Service manual lists "Standard" being 120-310S, "1 step lean" being 120-294S and "2 step lean" being 120-297S
Any thoughts would be greatly appreciated.
My 273 2bbl (BBD 4116SA CAP) smells like it is running excessively rich.
Forgot to mention I'm at 5000 feet now.
I rebuilt the carb 1 year ago, I have put 1000 miles on it since. Drivability and acceleration are normal, idles OK, No stumbiling or bogging down. I may have done something wrong in the rebuild but I have successfully rebuilt carbs for years so who knows.
The carb was originally jetted for sea level with the "Standard" jets and after sitting for 4 years and with old gas in the tank I had the car smogged. At that time it passed and all the values were relatively low.
A few weeks later I rebuilt the carb and installed a set of "2 step lean" jets 120-297S, I smogged it this year, still passed, but the values were significantly higher, HC went from 379 to 1358 at 2500 RPM. CO% went from 0.57 to 3.02 at idle.
Just found some info that says too lean will result in a raised HC level (lean misfire)
I was going to see if going back to the sea level (standard) jets would fix the issue but the OE jets are trashed.
Bottom line is I could use a set of 120-310S jets if anyone has some. Or what the ID of the jet is and I can drill out my 310s
The Service manual lists "Standard" being 120-310S, "1 step lean" being 120-294S and "2 step lean" being 120-297S
Any thoughts would be greatly appreciated.
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