May 5, 2019
My Z does not travel exactly straight when the arms are aligned
Tracking / Steering Adjustment / Alignment
Tracking is a term used for Zero Turn mowers that refers to the alignment of the levers in relation to the direction the mower travels. "Tracking Straight" means when you push the levers forward while lined up with each other on level ground that the mower will travel in a relatively straight line.
Expectations
It is not realistic to expect a mower to consistently track exactly straight as conditions are constantly changing. It's somewhat like being obsessed with the logo on our car steering wheel being exactly vertical when we are driving straight down the highway. Beginners often think they should perfectly align the levers to go straight, and while aligning the levers is a good place to start, the micro adjustments to go exactly the direction we want to go are to be made relative to the current direction and the current position of the controls. The same as we would do with the car's steering wheel without even thinking about which way the logo is turned. If we need to go a little more left then we adjust a little left regardless of where the controls are currently positioned.
A zero turn mower has two independent transmissions and simply put, one doesn't know what the other is doing and there is no gearing between them to keep them perfectly synched. But independent left and right wheel control is kind of the defining characteristic that makes zero turns so maneuverable.
The main variable that causes some variation in left vs right wheel speeds is additional resistance on one side or the other which can be caused by:
- Even the slightest slope to the left or right.
- Deck drag, because most zero turn decks are offset to one side, when we get into high grass pushing against the front of the deck it pushes more on one side than the other.
- Varying hydraulic fluid temperature which can temporarily differ from mowing across a bank/slope which puts more stress on the down hill transaxle causing it to be warmer, which differs the fluid resistance from one side to the other until the temperature equalizes again.
- One side of the mower being in a soft spot or hole or going over a root, etc.
- Varying tire pressure.
What we are saying is that if the tracking feels significantly off then adjust it. But if you are making tiny adjustments trying to find perfect then realize that it is somewhat of a moving target and it is nothing worth getting obsessed over. If it seems like it is pulling slightly left at one moment then it very well may feel straight or right in a few minutes.
Tracking in Full Reverse
A common rookie concern, particularly for those coming from steering wheel riders, is that when pulling both levers to full reverse the machine does not track straight but instead curves one way or the other. This is normal, and the good news is you will probably never see a situation where you need to travel full speed in reverse. One of the core advantages of a zero turn is that you can go head first into a tight area and then spin around and come out head first. Backing up straight can be achieved with some practice, but it is one of the least used skills because most operators only use it when backing onto a trailer or into a storage building and those are times where one would not use full speed.
But what if I just want it to go straight in full reverse because I’m a perfectionist and it’s bothering me. The issue is that the range of hydraulic flow varies slightly from one transaxle to the next, and the odds are slim to none for getting a left and right transaxle that have exactly the same range. That being the case when we adjust the forward travel speed that is simultaneously adjusting the reverse speed. That is to say that if we lower the max forward speed then we are raising the max reverse speed. So, when we get the max forward speed matched between left and right, whatever variance there is between the flows is going to show up as a difference in full reverse. If we then get it matched going backwards then it will be off going forward.
I Don’t Have Enough Power in Reverse
If you don’t have enough reverse power to back up a hill or up a trailer ramp, etc then first if your mower is a TimeCutter with Smart Speed then move the smart speed to the fastest speed. Otherwise, the tracking can be adjusted to move some of the forward power to the reverse end of the motion range. Assuming it is currently tracking straight going forward then both sides will need to be slowed equally going forward which will add speed/power to the reverse direction.
Aligning the Control Arms & Adjusting the Tracking
Before adjusting the tracking, first we should make sure the arms are aligned. To do this, turn the mower off, bring the arms in out of the park position, and push both arms all the way forward. If the arms are lined up with each other then we are done with this step. If not, then most models have a slotted hole around the top bolt where the handle mounts to the mower. This is to allow adjustment toward and away from the operator to a comfortable position. Loosen the bolt(s) as needed to get the arms in a comfortable position and also aligned when pushed all the way forward. Be sure to tighten the bolts well so that the arms don’t slip and move during operation. If aligning the arms does not fix the tracking issue then the next step is to adjust the linkage between the arm and transaxle on one side to match that of the other side. The adjustment to this linkage varies from one mower to another but will be explained in your owner’s manual. If you don’t have your owner’s manual and your mower is a TORO brand then you can find it online by entering the model at this page:
then click on the correct Serial Number Range, then click on “Manuals & Warranty”.
