paulbagley
New member
- Joined
- Jul 20, 2021
- Messages
- 4
- Tractor
- John Deere 316 and 320
I also posted this on another forum. Posing here since you guys have been very helpful with problems I've encountered.
I have a '93 JD 320 with a BDU-21 hydrostatic transmission that was having an odd issue.
It seemed to have plenty of pulling power, but going down hills was a bit of a Pinewood Derby experience. The hydrostatic would allow the machine to coast downhills and pick up speed.
Imagine an overweight late middle age male flying down a hill at double the unsafe speed, hands flung up to the heavens, and yelling "Wheeeee..."
Back in the garage with the machine I shut off I could roll it around easily without pressing the release lever on the hydrostatic transmission. When I tried the release lever it was already pressed down, lifting it up made no difference.
Last night I pulled the rear fender deck and gas tank to check things out. The release lever on the transmission presses a little button in the middle of the transmission. The button was stuck in.
I took the lever off so I could get at the release button. The cap takes a 9/16 box end wrench. The body work was held on by 14mm head hardware. Be sure to check your fastener sizes - my machine has both metric and English sizes.
When I had the cap off the release button I found it was stuck. I used a pair of pliers to gently pull it out a bit keeping everything as straight as I could. I put the cap back on, pressed it in again and it was stuck.
I sprayed a little PB Blaster in the hole and worked the button in and out a few times. I began to feel the spring helping to push the button back out after a repeat spray of PB Blaster.
When I was done I could move the button in and out with my fingers. Still a little sticky but a lot better. I put the cap back on and reassembled. Hopefully I have not created a leak - time will tell. The local JD Dealer was out of stock on the o-ring this morning
On a test drive around my yard there was no more coasting down the hills. Back in the garage I can press the release and it rolls. Stop pressing the lever and it locks up just as is should.
This machine has sat for a couple of years, ever since the previous owner went into assisted living. My guess is that the problem was caused by a bit of corrosion and lack of use.
Best part is that this was a "free" repair. All it took was some time and a little penetrating oil.
I plan to change the hydro fluid in the next few days. Any of the PB Blaster that got past the release button and into the transmission should drain out with the old fluid. I bought the low viscosity Hy-Gard and a filter from the local JD Dealer. Price isn't bad and it's the recommended fluid.
The local JD part guy is a bit of a crabby pants. I asked about the second hydro filter for the 320. He couldn't find it in his parts manual and told me I need to get the model number from the left side of the transmission. That is difficult - you'll need a mirror to read it or get a photo. Mine is a BDU-21L. And the second hydro filter is mounted on the bracket holding the control for raiding the deck/blower/blade. My filter is dated 6/92. Why was it mounted with the labels toward the frame? Easy enough to fix, and now I know the filter threads are not rusted together. Looks like the service specified in the manual was never performed in the 1000+ hour life of this machine. The fuel line also looked like vintage '92 and I changed it to avoid any issues this winter.
I hope someone finds this helpful.
I have a '93 JD 320 with a BDU-21 hydrostatic transmission that was having an odd issue.
It seemed to have plenty of pulling power, but going down hills was a bit of a Pinewood Derby experience. The hydrostatic would allow the machine to coast downhills and pick up speed.
Imagine an overweight late middle age male flying down a hill at double the unsafe speed, hands flung up to the heavens, and yelling "Wheeeee..."
Back in the garage with the machine I shut off I could roll it around easily without pressing the release lever on the hydrostatic transmission. When I tried the release lever it was already pressed down, lifting it up made no difference.
Last night I pulled the rear fender deck and gas tank to check things out. The release lever on the transmission presses a little button in the middle of the transmission. The button was stuck in.
I took the lever off so I could get at the release button. The cap takes a 9/16 box end wrench. The body work was held on by 14mm head hardware. Be sure to check your fastener sizes - my machine has both metric and English sizes.
When I had the cap off the release button I found it was stuck. I used a pair of pliers to gently pull it out a bit keeping everything as straight as I could. I put the cap back on, pressed it in again and it was stuck.
I sprayed a little PB Blaster in the hole and worked the button in and out a few times. I began to feel the spring helping to push the button back out after a repeat spray of PB Blaster.
When I was done I could move the button in and out with my fingers. Still a little sticky but a lot better. I put the cap back on and reassembled. Hopefully I have not created a leak - time will tell. The local JD Dealer was out of stock on the o-ring this morning
On a test drive around my yard there was no more coasting down the hills. Back in the garage I can press the release and it rolls. Stop pressing the lever and it locks up just as is should.
This machine has sat for a couple of years, ever since the previous owner went into assisted living. My guess is that the problem was caused by a bit of corrosion and lack of use.
Best part is that this was a "free" repair. All it took was some time and a little penetrating oil.
I plan to change the hydro fluid in the next few days. Any of the PB Blaster that got past the release button and into the transmission should drain out with the old fluid. I bought the low viscosity Hy-Gard and a filter from the local JD Dealer. Price isn't bad and it's the recommended fluid.
The local JD part guy is a bit of a crabby pants. I asked about the second hydro filter for the 320. He couldn't find it in his parts manual and told me I need to get the model number from the left side of the transmission. That is difficult - you'll need a mirror to read it or get a photo. Mine is a BDU-21L. And the second hydro filter is mounted on the bracket holding the control for raiding the deck/blower/blade. My filter is dated 6/92. Why was it mounted with the labels toward the frame? Easy enough to fix, and now I know the filter threads are not rusted together. Looks like the service specified in the manual was never performed in the 1000+ hour life of this machine. The fuel line also looked like vintage '92 and I changed it to avoid any issues this winter.
I hope someone finds this helpful.