2 cycle motor on a 25 year old lawn boy push mower

I'm guessing that maybe the jet is screwed in/out as a crude adjustment. Normally a jet would be nipped up tight and a needle adjusted...I'm guessing there's no needle?

I'd screw the jet home and try it, but count the half turns, so that you can return it to the original position if required.
Or maybe just try screwing it in a half turn at a time and testing.

If you have no joy I'm sure this forum will help you to race tune that sucker
Del

Back out 1-1/2 turns, rule of thumb.

It is a supprise if your engine doesn't have a needle! That's what you move in the jet when you operate the throttle.

Normally, you can adjust the hight of the needle by placing (what I would refer to)circlip in the right groove nd the jet supposed to be screwed in tight.

How can people who have never seen or worked on one of these offer advice?

Hmmm... let me see...
Maybe 'cos I'm not stupid ...and I've worked on plenty of 2-strokes and have actually seen a carburetor before...also general engineering practices are often transferrable from one discipline to another.

Whilst your full and explicite post is excellent, as you obviously have the pertinent experience, I don't think you will find anything wrong in my post #1.

Del

That's a good answer Keith, but Del is correct, a 2 stroke is a 2 stroke.

I've had my LB for about 20 years, very lite and powerful. Unfortunately, while on vacation, one of the kids grabbed the wrong gas can.....

Good winter project. Can you still get parts for these?

www.partstree.com

Thanks!

The jet needs to be screwed in tight. You adjust the fuel mixture by turning the screw/toothed wheel located ON TOP of the carburetor. Some 'legacy' float bowls have a water/trash drain on the bottom.

Correct my post #2 is irrelevant Thanks for forthrightness. The following are relevant observations.

Then remove the carb and valve plate and either replace the reed valves or turn them over if not too badly warped. They tend to 'bend' open with use, which causes hard starting rough idle, low power.

My 25 year old lawn-boy 2-cycle doesn't have the reed valve as the reed valve was introduced upon a later model.

One CAN drill out the carb body and install brass bushings, renewing the diameter. If the shaft is worn, one can either braze or solder fill and then file back to proper diameter to restore the close fit needed. I always retrofit felt 'seal washers' on the outside of the carb around the butterfly shaft to prevent dirty air ingestion and subsequent wear etc.

One CAN and graphite impregnated nylon works better as it may act as a seal also.