Is this the manual you are working from? Look at sect 4-4. The top port plug has to be removed from each transaxle, that is how the air will purge. There are pictures that show the operating position (closed) of the bypass rods
https://www.hustlerturf.com/file/114241.pdf

 

Walker 56, Your .pdf link is for a different machine. I have two expansion tanks. Yes it says remove the two top ports for filling with oil. It calls for the plugs to be reinstalled after filling then proceed to the purge process. Attached is the manual I'm working from. Thanks, John

 

You will need to pull them all the way out, they might look to be pulled out, but they're not. pull them all the way out.

Have the rear wheels off the ground, with both hydro's in free mode, push your sticks forward and backward 10 times slowly and fully. Then, put the bypass valves closed by pushing them back in. then proceed to drive. You will want to watch your hydro level in the resevoir to make sure you have enough as it will likely pull some in when you do the purge process.

my manual calls for 4 qts, but I have never had enough with 4qts, i typically end up putting about 4.5 qts in it.

 

Morning, so all the way out is open or closed? When open is this where the air escapges? The manual said to push the sticks back and forth in both modes, open and closed. Thanks, John

 

You got it. You will notice that when you pull on the valve it has a groove to lock it in place, or at least mine does. You'll know they are both open because the wheels won't spin when you are moving the sticks.

Just to be safe after i do hydro oil and filter changes, i purge twice, once right after, then i'll do it again in a week or 2 just to be sure i get all the air out. And yes, after you do it with the valves open, you close them and do the same thing, wheels will spin this time.

Remember not to overfill your reservoir either. Also, those filters are usually tight from the factory, so you'll want to get your hands on a filter wrench, not the handle kind but the kind that goes onto a socket wrench.

 

Thanks for the advice on the 2nd round of purging. It's working pretty good right now. Yeah, the filters were a real bi*** to get off. Later, John