On Mon, 4 Apr 2011 19:24:55 -0700, "PrecisionmachinisT"
wrote:


"jim" "sjedgingN0Sp"@m@mwt,net wrote in message
...


PrecisionmachinisT wrote:


Not on 99% of small engine garbs, you have an idle screw only and the
bushing wear cannot be compensated for because it will alter the mix
depending on the position of the throttle.

Pretty sure virtually ALL of mine do--I will have a look later.


If it is an older engine it will have an idle speed adjustment, idle
mixture screw and high speed mixture screw. Newer small engines often
have none of that.


Just as I thought...

I just finished checking a total of 3 chain saws, a of couple weed whackers,
a roto tiller and two generators that I have here--and each and every one of
them had a needle for idle and another needle for high speed and yet another
screw for adjusting for idle throttle position and so I must conclude that
anyone claiming that 99% of small engine carbs are lack an idle mix
adjustment most asssuredly is completely full of horse ****.

Oh, and FWIW, Karl's tiller in all likelyhood has a zenith 61 on it which
( not surprisingly ) also has an idle mix adjustment....

But hey if somebody wants to ****ing piddle around spending money and time
doing needless repairs on outdoor power equipment then more power to em I
guess.

--Just keep in mind the reality here is that reason Karl asked about it in
the first place was because he wanted to try and make sure that he wasn't
perhaps wasting time and money doing needless repairs....


I'll bet EVERY ONE of the engines you checked is over 5 years old.
Surprised if not 10 or more -Chain saws and some other 2 stroke
engines still have adjuster screws - but MOST have limiters on them
that require over-riding (read that as removing, breaking, or
otherwise defeating) in order to make any significant adjustment.

Virtually all CURRENT production small 4 stroke carbs have NO mixture
adjustment.

Also, with worn carb throttle shaft bushings, you can adjust until the
cows come home - and you WILL because any change in the relative
position of the shaft in the hole changes the position and size of the
leak. Leaking on the choke side has a lot less effect than on the
engine side of the throttle at idle.
You can make it idle perfectly, and run pretty darn good - and then
the idle will go all wonky - and it might idle perfectly the next time
without any change in adjustment.

If the shaft/bushings are badly worn, the only RIGHT thing to do is
fix or repair.