Craftsman carb issue

I found a Huayi carb from a 139cc mower engine. The idle jet body seems the same. The idle jet diameter is something between .011 and .014. I do not have all of the sizes to narrow it any closer. I tired that jet and it surged a bit. The outside temp yesterday was unseasonably warm at 70F. Of course it will surge a lot more at 20F. I am trying to decide if I should open it to about .014 and see what she does. If this does not work I am thinking a $50 MTD kit or an aftermarket carb from the most reliable source I can determine.
I have heard positive things about HIPA aftermarket carbs. I am Not sure if they have what I would need.
Thoughts from you experts?
 
Hello N.,

I just threw away 3 bleed air pilot jets this week due to broken off pin drill bits while working on my own generator. Honda clone pilot jets have the same dimensions as the ones I need, but the O-rings are just a little too fat.

Another key item to inspect carefully with a magnifying glass is the tiny O-rings on the pilot air bleed jets. They do not play well with being reused and the get deformed & brittle with age. Those O-rings will bypass unmetered air especially under load at high RPM. The O-ring on the tip is usually the problem one.

Use a little WD-40 when you install the pilot jets and they should slip in with a light finger top push.

I'm dealing with my 15KW Generac generator portable generator at the moment for similar (very slight) surge issues at high RPM.

I was able to find some genuine Honda pilot jet O-rings on eBay and am going to give them a try when they get here.

Otherwise, I will be looking for another carburetor and start all over again trying to get it tuned in. (Just because they say it fits, does not mean it will work correctly.)

Hope you get this figured out.
 
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