Motor will not rev up above half-throttle

[ChuckDion31]

I have a bad boy MZ Magnum. I know it's not a commercial mower, but it has done well for two years on my 1.5 acre property. Today I could not get the motor to rev up above half-throttle, even though the position is all the way forward. Any suggestions for trouble shooting will be greatly appreciated!

 

[bertsmobile1]

try to work the throttle manually by moving the governor arm on the carb
If it runs fine when you do this then either the cable clap has slipped so is not stretching the governor spring hard enough or the governor arm has slipped on the shaft.

 

[Mower King]

I have a bad boy MZ Magnum. I know it's not a commercial mower, but it has done well for two years on my 1.5 acre property. Today I could not get the motor to rev up above half-throttle, even though the position is all the way forward. Any suggestions for trouble shooting will be greatly appreciated!

Probably the clamp that holds the throttle cable in position has loosened up and let the throttle cable move. They are notorious for that to happen.
Some engines are worse than others as B&S and Kohler has their throttle assy on the bottom of the engine, right next to the exhaust & muffler, were all that heat does a job on the throttle cables and the clamp. Kaw has the right idea, the throttle assy on them are on the top of the eng, far from the heat!
All the new mowers I set-up, tightening the throttle cable clamp is part of my PDI after I set the RPM's......along with zip-tying the throttle cables up as far as I can away from the muffler!

 

[ChuckDion31]

Probably the clamp that holds the throttle cable in position has loosened up and let the throttle cable move. They are notorious for that to happen.
Some engines are worse than others as B&S and Kohler has their throttle assy on the bottom of the engine, right next to the exhaust & muffler, were all that heat does a job on the throttle cables and the clamp. Kaw has the right idea, the throttle assy on them are on the top of the eng, far from the heat!
All the new mowers I set-up, tightening the throttle cable clamp is part of my PDI after I set the RPM's......along with zip-tying the throttle cables up as far as I can away from the muffler!

I am certain you are right, I can't wait to check it in the morning--I'll post ASAP! Thank you so much!

 

[ILENGINE]

Probably the clamp that holds the throttle cable in position has loosened up and let the throttle cable move. They are notorious for that to happen.
Some engines are worse than others as B&S and Kohler has their throttle assy on the bottom of the engine, right next to the exhaust & muffler, were all that heat does a job on the throttle cables and the clamp. Kaw has the right idea, the throttle assy on them are on the top of the eng, far from the heat!
All the new mowers I set-up, tightening the throttle cable clamp is part of my PDI after I set the RPM's......along with zip-tying the throttle cables up as far as I can away from the muffler!

Not all the Kawasaki's are on the top. Working on a Toro right now where the linkages are on the bottom next to the muffler.

 

[Mower King]

Not all the Kawasaki's are on the top. Working on a Toro right now where the linkages are on the bottom next to the muffler.

Another bad design.

 

[ChuckDion31]

Not all the Kawasaki's are on the top. Working on a Toro right now where the linkages are on the bottom next to the muffler.

Not all the Kawasaki's are on the top. Working on a Toro right now where the linkages are on the bottom next to the muffler.

When I asked the question, I was concerned that it may have been a problem with the two cables on the carburetor, but thanks to mower king's advice, I found out that my problem was caused by two inches of melted plastic. I cleaned that up and removed the factory cable clamp and put a flat, square washer toward the motor, then the cable, then the factory clamp. It's back to normal! Thank you!