I posted a few days ago (hydrolic problem). The problem ended up being item 15 and 19 in this picture . What would cause this problem . The o ring was in two pieces and one of the plastic washers was in several pieces. Thanks Robby http://www.johnstractor.homestead.com/files/HydPowerLift.jpg
Three pt lift hydrolic problem
- Thread starter jaroban
- Start date
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Affordable
Advertiser, Platinum Member
Did you get it fixed ?? We have the rebuild kits in Stock
Tommy
Affordable Tractor Sales
Tommy
Affordable Tractor Sales
I did get it fixed. I do have questions about the seals for the banjo fittings. Some had alumum washers some had rubber coated washers and some had a washer with an o ring attached to the inside. I do not know what is the right combonation. I would like to know what would cause this to hapen. Thanks Robby
RonMar
Elite Member
Well those parts look like the piston seal. If the piston extended too far out of the cylinder, that could cause damage to these parts. I have read in the archives here about damage to the 3PH piston seals from misadjusted 3PH control linkage(automatically kicks control valve into hold position at top of 3PH lift) allowing the piston to extend too far before the linkage stops the movement.
Looking at the one on my tractor, the last time I was in the reservoir, there is a stop on the rear plate of the reservoir. It is part #42 on the diagram you linked to and appears to physically prevent the piston from extending too far and damaging the seals. I have not actually extended the piston till the linkage is on this stop pin(my control linkage adjustment prevents this), so I cannot say this is for certain. That stop pin may just be there to physically limit the vertical travel of the upper 3PH arms when you back an impliment into/up onto something.
I also fail to see how a leaking piston seal on a single acting cylinder could " put a strain on the motor(tractor running" when you try to lower it. That is why I thought you had a valve problem.
Glad you got it fixed.
Looking at the one on my tractor, the last time I was in the reservoir, there is a stop on the rear plate of the reservoir. It is part #42 on the diagram you linked to and appears to physically prevent the piston from extending too far and damaging the seals. I have not actually extended the piston till the linkage is on this stop pin(my control linkage adjustment prevents this), so I cannot say this is for certain. That stop pin may just be there to physically limit the vertical travel of the upper 3PH arms when you back an impliment into/up onto something.
I also fail to see how a leaking piston seal on a single acting cylinder could " put a strain on the motor(tractor running" when you try to lower it. That is why I thought you had a valve problem.
Glad you got it fixed.
bluechip
Veteran Member
I think at one time that stop cast into the rear cover might have functioned to keep the piston from overextending, but I'm thinking the casting patterns have worn or the piston design has changed. Most of the customers that I have had that had this happen on Jinma and Farm Pro tractors had just finished using a post hole auger or for some reason had to raise the 3 point just a little higher and moved the position of the jam nuts that control how high the lift will go.
I'm thinking he was leaving the lever in the up position in an attempt to "hold" the weight, that would load the engine.
I'm thinking he was leaving the lever in the up position in an attempt to "hold" the weight, that would load the engine.
I have been out of town for the last 4 days. There is no stop on my piston. There may be some sort of control valve problem however the tractor is doing what it is susposed to do know. All the seales looked good when I took it apart. Thanks for the info, Robby
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