On Dec 19, 11:17*pm, E Z Peaces wrote:
Jay Chan wrote:
On Dec 17, 7:11 pm, Jay Chan wrote:

I have received the tachometer. *I immediately try it and find that
the engine can run close to the manufacturer's suggested speed (3600
rpm) when I set the speed lever to high speed. *But the problem is
that when I set the speed lever to low idle speed, the engine still
run at high speed (3400 rpm instead of 1700 rpm as what the
manufacturer's suggested speed). *This means I have a problem.

If it happened to me, I'd dial the tach back to 1700 and see if it
showed just one mark. *If it's a strobe, it can read 2x, 3x, or 4x the
actual RPMs.

If it really is idling too fast, maybe you need to adjust the idle-speed
screw. *It's a screw the throttle bumps when it closes. *All carburetors
used to have them.

Each time you unscrew the idle-speed screw a little, you adjust the idle
mixture needle for the fastest idle. *Then unscrew the idle-speed screw
a little more.

No, the tachometer doesn't have the option to see the number in 2x,
3x... This tachometer shows the actual rpm of the engine shaft, not
the number of sparks from a spark plug.

I tried adjustng the idle speed mixing needle; but that didn't make a
difference.

In the past weekend, I tested the snow thrower with real load (12" of
snow), and I found that I could not make the throttle valve open more
than just a little. Anyway, the snow thrower was working fine and
could throw snow 20-ft away _if_ the snow was not wet.

At this point, I have decided to live with the minor problem of
"cannot slow to idle speed". I could not run the engine at idle speed
since I received the snow thrower as a "hand me down". I don't have a
need to run the engine in idle speed any way.

After I have cleaned the carburetor and adjusted the high speed mixing
needle, I have found the following good things:

(1) I can run the engine without any choke (that had been bothering
me for two years).

(2) I can pull start the engine with just one pull. I used to always
use electric start because hand pull didn't work before from day one
when I received it.

(3) I can put the speed lever to idle and the engine doesn't stop
(that I could not do from day one) (the engine is still running in
high speed though).

All in all, there are a lot of positive things. Therefore, I am happy
with the outcome. And I consider all these positive things as X'mas
gifts to myself (in addition to a Rockwell SoniCrafter power tool that
I have ordered for myself).

Thanks for everyone who has replied and helped.

Jay Chan