Toro 3500D decks will raise but will not stay up Cancel The title field is required!

1. Sean Donnelly

   

   8 posts
   
   9/11/2018 5:09 AM

   My Toro 3500D model#30821 (3211 hrs) has developed a problem where the decks will raise but then slowly drop. A little history at 3120 hrs I replaced the front lift cyl with a R&R unit #112-9916 worked 100%. At 3126 new fluid and filter was installed and suction filter was cleaned. At 3211 hrs the decks started dropping. I then replaced the rear lift cyl with the same R&R unit as I noticed the seal on the cyl was leaking. This did not solve the problem. I then checked the lift and steering control relief valve and pressue was good by FSM. Interestingly sometimes the decks stay up when the machine seems to be warmed up.
   
   In the book it states possible causes lift cyl leak internally or check valve within the lift control leaks. Where is the check valve in the lift control located?

   
   
   
   
2. Jody Farber

   

   14 posts
   
   9/18/2018 12:09 PM

   If I'm not mistaken, the check valve is where you'll want to look. It should be on the top of the control valve. Remove the black cover, and look for the plug in the same line as the lift/lower valve. Check/replace the spring in that one. I've had this issue with a 3500 and also a 3100-D (same valve).