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klondike
05-17-2005, 07:55 PM
My ZTR mower will roll if you push on it even though the dump valves are closed. I checked it with the drive wheels off the ground also. You can easily rotate the wheels by hand. The machine still has enough power to operate, but the left side is stronger than the right. Also it breaks away easily when pointed down hill. This is a real nuisance. It also moves while trailering if there are no straps holding it. I read the owners manual and performed the air bleed procedure, adjusted tracking, and neutral return position. I also checked hydraulic fluid level and saw no air bubbles. There are no abnormal noises coming from the pumps.

I have a Wright Sentar with BDP 10L pumps. Machine was a dealer demo. It did this from the time I got it, which was at 72 hours. It now has 200 hours and is getting a little worse.

Restrorob
05-17-2005, 08:12 PM
My ZTR mower will roll if you push on it even though the dump valves are closed. I checked it with the drive wheels off the ground also. You can easily rotate the wheels by hand. The machine still has enough power to operate, but the left side is stronger than the right. Also it breaks away easily when pointed down hill. This is a real nuisance. It also moves while trailering if there are no straps holding it. I read the owners manual and performed the air bleed procedure, adjusted tracking, and neutral return position. I also checked hydraulic fluid level and saw no air bubbles. There are no abnormal noises coming from the pumps.

I have a Wright Sentar with BDP 10L pumps. Machine was a dealer demo. It did this from the time I got it, which was at 72 hours. It now has 200 hours and is getting a little worse.


I ran across the same problem on 2 MTD Pro ztrs,After bumping my head againest the wall I decided to put a wrench on all the lines and make sure they were tight....Low in behold I found a little dirt around a return line fitting and it was a little loose,Tightened it up performed the air bleed procedure and sent them home. They were sucking enough air to cause the problem.
You mite try this on yours,Its a no cost possible Fix.

klondike
05-17-2005, 09:36 PM
I checked all the fittings. It does seem like some of the flared fittings on the suction side would turn some more. I went as tight as I dare and repeated the bleed procedure. The wheels still roll with a push and spin freely with the drive wheels off the ground. I ran out of daylight. I will repeat this tomorrow.

Restrorob
05-18-2005, 08:16 AM
I checked all the fittings. It does seem like some of the flared fittings on the suction side would turn some more. I went as tight as I dare and repeated the bleed procedure. The wheels still roll with a push and spin freely with the drive wheels off the ground. I ran out of daylight. I will repeat this tomorrow.


I slept on this problem and I remembered I was able to turn the wheels on the MTD also when jacked up,Dealer Support told me not to worry about this, They said this configuration of system would not completely lock down when not running.These units were only 6 mos. old at the time and that was some 2yrs. ago. By chance just yesterday one off these same units was dropped of with a no start problem,Just for the heck of it I jacked the back up and was still able to turn the wheels and the hydro system is still doing fine.
I would worry more about loss of power on one side than free spin.
Also check All seals for lite dirt collection,This problem just sounds all too familiar,I could very well be wrong in this case but this has only cost a little time to eleminate this possibility before spending big bucks on hydro units.

klondike
05-18-2005, 04:29 PM
I disconnected the cable from the weaker right side pump. This allows me to move the forward/reverse bar through its full travel. The speed on the right side now matches the left. I just need to figure out how to achieve this with the cable connected. When I shorten the cable I gain speed in reverse, but at the expense of forward speed. When I lengthen the cable to match the forward speed of the left side, I lose reverse speed. There must be another component that needs adjusting.

Regarding the freewheeling. I have a walkbehind scag with BDP 10L pumps but probably different wheel motors. I can't move this mower an inch unless the dump valves are open. So I wonder if its a combination of the larger diameter wheel on the ZTR and possibly a different wheel motor. I will make one more attempt to find and tighten any loose connections. Thanks for your help so far.

ed2hess
05-18-2005, 04:41 PM
We have a brand new Scag Tiger Cub and I noticed that when I take the hand brake off I can roll the unit easily. Guess something has changed on these pumps. On our Snapper 36" hydro no way can you push it without takign off the pressure valve.

Restrorob
05-18-2005, 08:21 PM
Just by chance I had a Customer come in this morning,He bought a new Dixie Chopper but he wanted the style tires that was on another unit,So you know what I got to do,Swap tires out and while up in the air I was able to free spin the tires on both units. I guess most you can and some you can't.
Keep us posted.

klondike
05-19-2005, 01:07 PM
Continuing progress. I guess there is something different about newer units and free wheeling. I still cannot properly balance forward and reverse travel. I removed all the cables on both pumps and watched carefully as I moved from neutral to reverse. I noticed the left pump spins the tire immediately when you move the shaft from the neutral position. The right pump has a small amount of dead zone. The right pump seems to catch up with the left side at the full travel position. Unfortunately the cable mechanism doesn't allow for 100% travel in both directions by design. They try to keep you from slamming the pump components against the internal stop. So I guess I have something worn with the right pump. At least now I won't panic if the rebuilt hydro still allows the wheels to spin with the dump valve closed.