The whine is your hydro pump. The machine is run by independant hydraulic motors at each wheel that the pump feeds through the use of a valve system. Although a loud whine may not be a good thing, you can expect a little whine. It has noting to do with the engine but check your hydro fluidfor the drive system. If it is low or has air in the system, it can make the whine more predominant. As a landscaper I have never encountered a machine without asome sort of whining noise from the hydro's. As a small engine mechanic with over 30 years experience, I can tell you that if the hydro fluid is at the correct level and the system has no air, the noise should be barely noticeable.

 

Most every Zturn ive been on[and thats a lot] have some whine. More so when the engine speed is slow. Even full speed it will have a little, but you will hear it most at slow engine speed, during transitions of the sticks.

 

Is it normal to hear a whine when moving the sticks on a zero turn? It drives fine, straight, and plenty fast, but I hear a noticeable whine when moving or turning. The sound isn't specific to either side and I only hear it when I move or turn the mower. Sounds much like a power steering pump on a car. It's not crazy loud but it is noticeable. I'll be changing the oil and filters soon because I have no idea when or if it has ever been serviced.

It's a used Hustler 54 Fastrack SD, and my first mower with a hydro. I'm still learning what, how, and why things are they way they are on this machine.

Also, it has a freshly rebuilt Kohler 25 horse engine with 6 hours on it. How soon should I do the first oil change and when can I start using synthetic? I Googled. Answers are solid for a brand new machine, but for a rebuilt motor they are all over the place, range from 1 -10 or more for dino oil and up to 50 before switching to synthetic. 50 sounds crazy to me.

Thanks for any info. Randy

At 6 hrs I'd change the oil now and again in 10 hr. And switch to synthetic oil. Small engine conventional oil is getting hard to find for me.

The whine is normal from hydro units . how many hrs are on the hydro units ?

 

Hours on the hydro? I have no idea. I bought the mower from my neighbor, and he got it free from a friend who kicked a rod through the block when he drained the oil and forgot to refill it. My neighbor took it to a shop where they replaced the blown Kawi with a rebuilt Kohler CV730. He buys and flips RV's, boats, etc. and I'm sure that was his plan for this one until he got it back. It had some idle and surging issues he could not resolve so he sold it to me for what he spent on the rebuilt motor. There's a LOT more to that story, about a year's worth, but he just wanted it gone. He already owns a Hustler 60" and had no need for this one.

The hour meter was dead when I got it so I'm in the dark on how much it was used, but overall it looks to be in great shape. Not beat up or battle scarred at all. I've been working the kinks out of it for about a month. It's a beast compared to my 46" Murray.

I really appreciate the replies.
Randy