On my JD 4200 I have repaired the o-ring on rate of down valve 2 times in the last year. Yesterday it happened again. Question is what would be causing the o-ring to let go? In both instance that it let go I was working the 3 pt. hard (lot of up and down motions) with my gill pulverizer. Was wondering if debris is in the hyd. oil and that was chewing up the 0-ring. Any other possibilities that may causing this to happen. As we all know it always breaks down when busy.
Rate of down valve?
- Thread starter yod67
- Start date
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Couple of things I'm considering: heat from over use? last two o-ring wasn't john deere parts they were from a local part store? Original o-ring lasted 8 years. debris in the oil? just a couple of thoughts is there any more?
tbenn7362
Member
temperature and proper oring. there are a lot oring materials out there. i would get the oem one. I dont believe even dirty hyd fluid wont hurt it. Do you adjust it alot? that might wear it out sooner
Mechanos
Veteran Member
It's likely that the parts store replacements may be made of a different material and/or have a different Durometer spec than the original.
kennyd
Advertiser
I agree...try a JD part and see if it holds up better.
I never adjust the rate of down knob. Just ordered a original one today from John Deere but fix it with a part store one. The last o-ring lasted about 2 weeks. I Needed the machine to work today. Thanks for all the relpies.
BCinVA
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How does the o-ring look when it is removed. Is it chewed up? Maybe there is a burr or debris in the valve that is damaging the o-ring. It may be worth inspecting the area in the valve where the o-ring seats. Also I have had situations where if the o-ring is not exactly the right size it can be damaged on installation.
Just some random thoughts.
Just some random thoughts.
Yep o-ring was chewed up on one side. The valve sits in a position that it is hard to look in. After I had the valve out I turned over the engine to flush if any debris out. Valve measures about 1 1/2" x 1/2" round and the o-ring fits in a slot.
RoyJackson
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Just to use the correct terminology, it's the "Rate of Drop" valve.
