B7200 Hydraulic Loader Cylinder repair
- Thread starter avpowerstn
- Start date
So I know this thread is old, but I figured I'd give the original author his due. Thank you sir, your effor is paying dividends a decade later!
I have my dad's old B6200 HST-D with B1640 FEL from the 80s and the bucket was drifitng down (in curl). Really annoying when loading wood and travelling any distance. These directions in this thread proved invaluable, as nobody (dealers/mechanics) wants to work on these anymore, but a seal change makes all the difference, especially after not having hydraulics services in >12 years.
Things I will add to contribute to this thread:
1. The cylinders are held closed by an internal retaining ring. I found mine after scraping out a bunch of mud/dirt from >12 years of use. Get yourself a good set of 0.070" 90-deg retaining ring pliers (i.e. snap-on, blue-point, or their OEM, Lang tools), as the cheapo HF or even Channel-lock pliers wont have the right tips to take the tension these suckers have on them. I know, lots of swearing and time sunk in because of inferior tools. Spend the $, trust me.
2. The difference in the cylinders for Curl vs Lift is the diameter of the rod itself. Lift rod diamerer is 1.125", and Curl is 1.00." The outer dims of the cylinders themselves are equal, and I found someone swapped a curl cylinder for a lift in my FEL, completely messed me up in my repair adventure (i.e. "why won't the seals slide on the shaft, worked fine the first time!")
3. Kits for repair from Kubota are getting extremely hard to come by. They come with shims, snap rings (both which can be re-used if you don't destroy them when disassembling) and nylock nuts. The Nylocks should be re-usable considering the vibe environment and the fact they aren't removed several times, it's a small tractor and not an airplane.
4. Regarding kits, recommend bringing your rod/pison assembly to a replacement hydraulic parts supplier. In New England, I suggest visiting Mechanics Bliss (MB Supply Co.) in Worcester, MA: Mechanics Bliss, Worcester, MA
If you bring in the cylinder disassembled and cleaned up o them, they will literally make you a kit piece-by-piece (seal by seal). They're all "standard" seals and in stock, but Kubota stopped getting wipers and hallite seals bundled together a long time ago. My cost per cylinder in December 20234 was ~$30 instead of ~$90 from the local Kubota dealer or Messicks. I'll try to post a BOM later that worked for my cylinders/pistons.
FYI, that shop also makes hydraulic cables pretty fair priced, much cheaper than a Kubota dealer. They didn't use Parker Hannifin tubing, but I'm sure their tubing will hold up just fine. This place will even make you fire hose too if you're in need!
5. As a general rule, the rubber o-ring (or in the case of the pistons, the cupped end) goes toward the inside of the cylinder, where the high pressure is. The cups fill with hydraulic fluid upon compression and actually tighten the seal. That tripped me up in directionality.
6. Internal seal pliers from Amazon work great and save some headache. You can do a similar function with some long-nosed needle-nose pliers, but you'll swear more. Depending on your annoyance threshold (I was working on this in the barn in 30-deg weather), it was worth biting the bullet. Unfortunately, Amazon is it, HF doesn't sell this tool (surprisingly).
Thanks for all the great minds that contribute to this community. It's 2024, $%^& is expensive and not everyone can just "go buy a new one." Re-habing 80's equipment built like a tank is often much more cost effective, and in my opinion, a lot greener too (who wants to calculate the "carbon footprint" in manufacturing a tractor? I bet it's less to replace the rubber seals
)
For $120 in new rubber/plastic, and the awesome visual directions in this post, you can get your FEL back up and without the droop etc, vs thousands (and the cost of disposing an otherwise fixable tractor/loader).
I have my dad's old B6200 HST-D with B1640 FEL from the 80s and the bucket was drifitng down (in curl). Really annoying when loading wood and travelling any distance. These directions in this thread proved invaluable, as nobody (dealers/mechanics) wants to work on these anymore, but a seal change makes all the difference, especially after not having hydraulics services in >12 years.
Things I will add to contribute to this thread:
1. The cylinders are held closed by an internal retaining ring. I found mine after scraping out a bunch of mud/dirt from >12 years of use. Get yourself a good set of 0.070" 90-deg retaining ring pliers (i.e. snap-on, blue-point, or their OEM, Lang tools), as the cheapo HF or even Channel-lock pliers wont have the right tips to take the tension these suckers have on them. I know, lots of swearing and time sunk in because of inferior tools. Spend the $, trust me.
2. The difference in the cylinders for Curl vs Lift is the diameter of the rod itself. Lift rod diamerer is 1.125", and Curl is 1.00." The outer dims of the cylinders themselves are equal, and I found someone swapped a curl cylinder for a lift in my FEL, completely messed me up in my repair adventure (i.e. "why won't the seals slide on the shaft, worked fine the first time!")
3. Kits for repair from Kubota are getting extremely hard to come by. They come with shims, snap rings (both which can be re-used if you don't destroy them when disassembling) and nylock nuts. The Nylocks should be re-usable considering the vibe environment and the fact they aren't removed several times, it's a small tractor and not an airplane.
4. Regarding kits, recommend bringing your rod/pison assembly to a replacement hydraulic parts supplier. In New England, I suggest visiting Mechanics Bliss (MB Supply Co.) in Worcester, MA: Mechanics Bliss, Worcester, MA
If you bring in the cylinder disassembled and cleaned up o them, they will literally make you a kit piece-by-piece (seal by seal). They're all "standard" seals and in stock, but Kubota stopped getting wipers and hallite seals bundled together a long time ago. My cost per cylinder in December 20234 was ~$30 instead of ~$90 from the local Kubota dealer or Messicks. I'll try to post a BOM later that worked for my cylinders/pistons.
FYI, that shop also makes hydraulic cables pretty fair priced, much cheaper than a Kubota dealer. They didn't use Parker Hannifin tubing, but I'm sure their tubing will hold up just fine. This place will even make you fire hose too if you're in need!
5. As a general rule, the rubber o-ring (or in the case of the pistons, the cupped end) goes toward the inside of the cylinder, where the high pressure is. The cups fill with hydraulic fluid upon compression and actually tighten the seal. That tripped me up in directionality.
6. Internal seal pliers from Amazon work great and save some headache. You can do a similar function with some long-nosed needle-nose pliers, but you'll swear more. Depending on your annoyance threshold (I was working on this in the barn in 30-deg weather), it was worth biting the bullet. Unfortunately, Amazon is it, HF doesn't sell this tool (surprisingly).
Thanks for all the great minds that contribute to this community. It's 2024, $%^& is expensive and not everyone can just "go buy a new one." Re-habing 80's equipment built like a tank is often much more cost effective, and in my opinion, a lot greener too (who wants to calculate the "carbon footprint" in manufacturing a tractor? I bet it's less to replace the rubber seals
)For $120 in new rubber/plastic, and the awesome visual directions in this post, you can get your FEL back up and without the droop etc, vs thousands (and the cost of disposing an otherwise fixable tractor/loader).
For anyone needing a BOM for new replacement seals for their 1640 loader with the earlier serial numbers < S/N 24005472, considering the Kubota parts are all discontinued and old stock is dwindling quickly, here’s my list. Seals were all purchased from Mechanics Bliss, linked above. I believe they do mail order as well.So I know this thread is old, but I figured I'd give the original author his due. Thank you sir, your effor is paying dividends a decade later!
I have my dad's old B6200 HST-D with B1640 FEL from the 80s and the bucket was drifitng down (in curl). Really annoying when loading wood and travelling any distance. These directions in this thread proved invaluable, as nobody (dealers/mechanics) wants to work on these anymore, but a seal change makes all the difference, especially after not having hydraulics services in >12 years.
Things I will add to contribute to this thread:
1. The cylinders are held closed by an internal retaining ring. I found mine after scraping out a bunch of mud/dirt from >12 years of use. Get yourself a good set of 0.070" 90-deg retaining ring pliers (i.e. snap-on, blue-point, or their OEM, Lang tools), as the cheapo HF or even Channel-lock pliers wont have the right tips to take the tension these suckers have on them. I know, lots of swearing and time sunk in because of inferior tools. Spend the $, trust me.
2. The difference in the cylinders for Curl vs Lift is the diameter of the rod itself. Lift rod diamerer is 1.125", and Curl is 1.00." The outer dims of the cylinders themselves are equal, and I found someone swapped a curl cylinder for a lift in my FEL, completely messed me up in my repair adventure (i.e. "why won't the seals slide on the shaft, worked fine the first time!")
3. Kits for repair from Kubota are getting extremely hard to come by. They come with shims, snap rings (both which can be re-used if you don't destroy them when disassembling) and nylock nuts. The Nylocks should be re-usable considering the vibe environment and the fact they aren't removed several times, it's a small tractor and not an airplane.
4. Regarding kits, recommend bringing your rod/pison assembly to a replacement hydraulic parts supplier. In New England, I suggest visiting Mechanics Bliss (MB Supply Co.) in Worcester, MA: Mechanics Bliss, Worcester, MA
If you bring in the cylinder disassembled and cleaned up o them, they will literally make you a kit piece-by-piece (seal by seal). They're all "standard" seals and in stock, but Kubota stopped getting wipers and hallite seals bundled together a long time ago. My cost per cylinder in December 20234 was ~$30 instead of ~$90 from the local Kubota dealer or Messicks. I'll try to post a BOM later that worked for my cylinders/pistons.
FYI, that shop also makes hydraulic cables pretty fair priced, much cheaper than a Kubota dealer. They didn't use Parker Hannifin tubing, but I'm sure their tubing will hold up just fine. This place will even make you fire hose too if you're in need!
5. As a general rule, the rubber o-ring (or in the case of the pistons, the cupped end) goes toward the inside of the cylinder, where the high pressure is. The cups fill with hydraulic fluid upon compression and actually tighten the seal. That tripped me up in directionality.
6. Internal seal pliers from Amazon work great and save some headache. You can do a similar function with some long-nosed needle-nose pliers, but you'll swear more. Depending on your annoyance threshold (I was working on this in the barn in 30-deg weather), it was worth biting the bullet. Unfortunately, Amazon is it, HF doesn't sell this tool (surprisingly).
Thanks for all the great minds that contribute to this community. It's 2024, $%^& is expensive and not everyone can just "go buy a new one." Re-habing 80's equipment built like a tank is often much more cost effective, and in my opinion, a lot greener too (who wants to calculate the "carbon footprint" in manufacturing a tractor? I bet it's less to replace the rubber seals
For $120 in new rubber/plastic, and the awesome visual directions in this post, you can get your FEL back up and without the droop etc, vs thousands (and the cost of disposing an otherwise fixable tractor/loader).
Sorry I couldn’t figure out how to copy the table directly into the thread (gave me code errors), it’s in the photo attached.
Many of the parts are common, others that aren’t are called out specifically for lift (1.125” diameter) vs bucket (1.00”) for the gland seals.
Attachments
Last edited: