HS40 Carb adjustment

[copyman]

Hi,

Never saw this before...
Rebuilt a 1971 HS40 with slanted intake. Engine didn't come with a carb so put on a genuine TEC carb I had rebuilt. Think it was off an H60. Motor started fine and idles ok but when I go to adjust the high speed screw on bottom of bowl the engine starts to rev really high until I back out screw a little. I know the screw is suppose to adjust top speed but it's revs way to fast to where it could blow engine! Not sure and will confirm but also if I open choke lever up all the way engine revs really high until I put back to middle notch. Like I mentioned it idles good.

Thanks for any info.

 

[creia]

Doesn't an H60 carb have a larger venturi (and higher airflow) than a HS40 carb? How about the jets and carb passageways? I would think they would be different (larger) as well. If the carb is mis- matched to the engine that might explain the odd symptoms you are getting...
Michael

 

[copyman]

Thanks. I had a feeling it could be the carb and why I mentioned it in my OP. I will try a different carb.