Small Engines (Lawn Mowers, etc.): Toro Zmaster 52 midsize frame, kawasaki engine, tim parrish


Question
19 HP Kawasaki Engine v2

Can I increase the operating RPM safely. (How?)
3600 is the claimed and the best I can get is 3400. I am willing to reset the governor. Also adjust valves or rejet carb, change cam. Any advice you can give would be nice.

I use the mower as a mulcher exclusively, and have fiddled with the governor mount plate adjustment with some success.

If repowering is the only reliable option do you have an engine recommendation?

Thank You,

Tim Parrish

Answer
Tim:

You need to look at the specifications from TORO.  I belive you are talking about the engine documentation that says you have a 19hp engine at 3600 RPM.  This is a common misconception and has confused buyers for years, that is why now you see push lawnmowers rated in torque, not horsepower.

For Example a walk behind lawnmower engine is rated at 6.5 horsepower at 3600RPM...BUT the engine can only turn at 2400RPM because of blade length...So you really are only using like 3-4 to 4 hp of the 6.5 hp engine...does this make sense..

I do not know what the operating specs on your Zmaster are I am going to refer you to your Toro dealer to get the specs for your unit.  

To adjust the gov, it is usually nothing more than turning the gov adjustment screw in or out to obtain your desired engine speed.  There is no need to change carb, adjust valves etc...

I can not stress enough, make sure you do not exceed the recommended RPM specs from Toro.