Kohler 149cc hard to start fix.

[KrisZ]

Thought I'd share this easy fix.

This will probably apply to similar engines with auto choke and RPM governor.
I noticed that over the last several months my lawnboy was hard to start cold and even hot. It used to take one or two pulls to get it started, but now it took 5,6,7 or so.

The spark plugs were very sooty so I looked for a low or high fuel mixture screws and of course there is none. I then started reading and most topics were about adjusting the automatic RPM governor, so I looked at mine. The tab looked slightly bent.
I adjusted it with the engine running by ear and not only does it run better, it starts on first the pull.

 

[BrianF]

Nice! Thanks for the info.

 

[Linctex]

????

Almost all small engines start at "full throttle" due to governor spring tension.
When the engine starts, the governor arm moves down to regulate speed.

I don't see how this is a "fix"

 

[bubbatime]

Many "single speed" small engines have a bendable tab that the governor spring is mounted to. You bend the tab one way to lower the RPM, you bend the tab the other way to raise the RPM. The op just found his bendable tab.

Look at the ops picture. If you bend the tab up, (as pictured, with pliers, with the red arrow), then it puts more spring pressure on the governor, and raises the RPM.

I bend EVERY tab on my engines to raise the RPM a bit. Runs better, cuts better. Blade safety regulations be darned.

I've even found mowers in the trash for this very reason. Engine only runs at like 2500 rpm, barely cuts anything. Bend the tab to raise the RPM back up to 3100 RPM, mower works fine.

 

[KrisZ]

Bubbatime, you got itðŸ‘

And in my particular case it must've also affected the choke because I noticed a puff of black smoke at hot restarts and like I mentioned in OP, the spark plug was black, indicating running rich. Given that there is no mixture adjustment on the carb, the choke is the only thing I can think of that could've done this.

It's too early to say if it will run leaner, but the spark plugs should turn brown with time if the mixture went back to normal.