C 175 carb adjustment

[little red riding horse 223]

need a little help... finally bit the bullet and fitted a cheap knock off carb ,though running  well (ish) its running rich (I think) its putting out black sooty smoke... so q is which screw do I adjust the one on top of carb or the one on the side ? and 2nd question , clockwise turn or anti ? 

Don't think its out by much as its running well , just annoyed with black soot over everything near exhaust outlet … 

Phil

[pfrederi 18,685]

Top screw In (clockwise) leans the mixture

[little red riding horse 223]

Good man ! 

[Stormin 9,985]

 The screw on the side is the idle mixture, As Paul has said, the screw on the top is for the main jet.

 

 According to the info I have, turn both screws fully in, then back off the main jet screw two turns. Back off the idle screw 1-1/4 turns. Start up and let the engine warm up.

 

  Run the engine at full revs and turn the mixture screw in until the engine starts to slow down. Then turn anti clockwise until it starts to slow again. Set the screw about halfway between the two.

 Do the same with the idle screw. The throttle stop screw should be adjusted so the engine idles at 1200 rpm. That's so the engine, being splash lubricated, gets sufficient lubrication.

 

 For setting the revs, I have a digital contact tachometer purchased from Machine Mart.

 

Edited July 27, 2019 by Stormin

[little red riding horse 223]

Hi Norm, thanks for the info …. ive taken the top screw clockwise about quarter turn or so and that has made big difference but the light wasn't great so will check again today and may have to delve in a wee bit deeper and use your method depending how it looks...

thanks for taking the time to reply 

Phil