Mower will not run wide open after 2nd start???

[farris35]

I have a Toro 21 inch mower with a GTS5 6 horse power engine.

The mower will start on the first pull when cold with the choke on and then we back of the choke and it will run real good.

After running it for 5 to 10 minutes if you kill it and restart it with out choking it seems like it runs at about 75% of full throttle.

I have tried to "trick" it and start it with the choke and back it off, but it will never run at 100% again.

Once it cools off for a day you can start it and it will run again at 100%.

I will add that when running at 75% it boggs down a little whereas when at 100% it cuts real good.

Any suggestions?

Thanks

 

[Rivets]

Try this, crack the gas cap open after restarting. It may have plugged vent hole thatbis allowing the creation of a vacuum. Opening the cap will break the vacuum and allow fuel to flow freely again.

 

[farris35]

Thanks for the reply. I tried opening the gas cap, but no luck.

 

[redfish9]

don't shut it off

 

[farris35]

I try not to, but we have 4 yards to mow.

 

[Rivets]

Ok, that was the easy one. Try #2 trip the mower up on it's side carb UP, and block it so it is about 12" off the ground. I rest it on a jack stand. Clamp off the fuel line, I use a vise grip pliers. Using a 1/2" wrench, carefully loosen the bolt on the bottom of the carb. Try to take just the bolt out and leave the fuel bowl attached. This bolt is also the main jet. Clean this jet throughly, there is a vertical and horizontal hole that must be clean. After cleaning reinstall and test. If the fuel bowl comes off clean it also and carefully reinstall, making sure that you get the rubber gasket in properly.