TT2 Throttle Problem

[Mowergal]

Replaced throttle cable late 2023 mowing season. Problem #1. This year, throttle lever does not increase engine rpm through throttle lever mid-range, not until lever is almost max forward position.
Problem #2- On full throttle lever position, engine does not seem to be at max rpm.
So, it seems these two issues are related.
I have a friend coming to check engine rpm. However, I am quite certain max rpm is not being achieved. Cuts fine, but engine sounds weak and labored.
2018/2019 Turf Tiger 2, Kohler 26.5 EFI. 625 hours. Residential use, lawn and several horse pastures.
Thank you for any suggestions as to what is wrong with the throttle mechanism.

 

[Bertrrr]

Pull off the cable connection at the carb- Move the throttle lever by hand until full throttle position, then move the throttle cable to Max speed then clamp down at that point, Now move throttle control and check for full travel , your new cable possibly doesn't have as much travel as your old one or you clamped it down in a different area.

 

[Mowergal]

Thank you! I will try this. I don't have a carburetor, it is EFI, but obviously that does not make a difference. Thanks again!

 

[GearHead36]

I don't have a Scag, but I DO have a Kohler EFI engine, and my throttle does something similar. It doesn't affect RPMs until the last half of the lever travel. Dropping this comment so I can follow this.

 

[Mowergal]

That is another way to describe the problem. On my machine, rpm's are not affected (do not increase), until the last 1/4 of lever travel...

 

[Tiger Small Engine]

That is another way to describe the problem. On my machine, rpm's are not affected (do not increase), until the last 1/4 of lever travel...

Until you check with a digital tachometer, you will not know for sure. Not uncommon for throttle control to have a section as you are increasing the lever, to have little to no affect on engine speed.

 

[Mowergal]

Until you check with a digital tachometer, you will not know for sure. Not uncommon for throttle control to have a section as you are increasing the lever, to have little to no affect on engine speed.

Until you check with a digital tachometer, you will not know for sure. Not uncommon for throttle control to have a section as you are increasing the lever, to have little to no affect on engine speed.

Thanks! Good to know!
Following through with suggestion above to check the cable and using tach to check rpm with my friend by end of the week!

 

[7394]

 

[Mowergal]

Pull off the cable connection at the carb- Move the throttle lever by hand until full throttle position, then move the throttle cable to Max speed then clamp down at that point, Now move throttle control and check for full travel , your new cable possibly doesn't have as much travel as your old one or you clamped it down in a different area.

 

[Mowergal]

We followed your recommendation, and yes, the cable was limiting full throttle, the lever now smoothly increases rpm as it moves forward.
At the same time, I also noticed that the fuel filter was installed backwards, against the flow of gasoline. This was the other factor limiting engine performance. We correctly installed a new filter, and in conjunction with adjusting the cable, I now have max rpm's!
Thank you everyone!