Yardman wrote:I did take out the throttle shaft and removed the butterfly to clean and insert a new throttle Seal. I have checked it several times and tried to insert the butterfly back in different ways. It turns out that there are only one ways to insert it back into the throttle shaft or it won't fit. My current setup for the butterfly disc is the two taps and the number stamp is on the right side and the Hole is on the bottom left (this is the end that connects to the engine). Also, the butterfly does move freely (open/close) without any restriction. Does anyone think the carburetor is still good or I should purchase a new one?
I think you should purchase a tachometer ($75 or so) and check your engine speed.
It may be possible what you thought was "normal" was actually poor power, and after fixing the carburetor, you restored its power to where it should be.
What size mower deck is it? The blade length determines engine RPM it should run at (And is the blade attached?)
Formula to determine engine RPM :
Blade length (In FEET - if it is a 21" mower, 21 divided by 12) , Multiply by PI (3.14) and multiply that figure by engine RPM, blade tip speed should not exceed 19,000 FPM
Assuming a 21" mower : 1.75 x 3.14 = 5.495 , x 3300 RPM = 18133.5 FPM blade tip speed.
As these engines are *designed* to run at pretty much a constant speed, as long as you are not exceeding 3300 RPM and it mows well, I would not worry about it -
However, my initial suspicion would be to closely inspect (when it is all put together) for some interference between the governor linkage and the starter blower housing - easy to bend the linkage and catch it up under the housing, so I would say pull the blower housing off, inspect the linkage for its full length between carburetor and governor arm, make sure it isnt binding somewhere.