jubilee issues

[jonesnjones]

I have a 53' jubilee with an external pump. I have rebuilt the entire hydraulic system from pump to piston/o-rings with new universal oil. the 3-point still wants to lift with the positioner arm all the way down. I have about 1800psi going to the piston. what could be my issue with it trying to lift all the time? I have no trouble lifting anything. if there is an entire covor plate for sale let me know. thanks for your time.

 

[Jbrink64]

I would be looking for a stuck valve. Either the control valve, unload valve or the back pressure valve. If they are all free, it's a linkage issue. There are a couple of adjustments in the lift cover that require a good manual, and the Ford special tools. If you're familiar with these lift covers, you can get away without the tools.

 

[Soundguy]

even if not familiar witht he cover or manual.. you don't need the nuday tools.. just have to be able to read a ruler to do the adjustments.

to the op.. will the 3pt still lift with a lil weight on it. IE.. set a concret block on the 3pt 11 hole drawbar.. is that enough to keep it from coming up?

and by external pump I take it to mean the REGULAR OEM right side mounted engine pump either the square vane design, or the repalcement cylindrical piston pump. if the piston pump, is it the oem 2.85 gpm one.. or a later repalced 4gpm one from a hundred series. if so.. that may be part of the issue. the exhaust capability of that system was designed for about 3gpm max flow... with more flow there is more backpressure.. thus the 3pt can ghost rise if there is no weight on it.. if a lil weight helps, and you are using a correct thin UTF style oil.. i'd check to make sure the oil was clean and not milky, and check the positioning of the BP valve too.

Might run a gallon of diesel into the sump and some atf fluid and cycle and run around for 10 minutes, then drain and refill if the sump had any sings of dirt or emulsified water in it. if water.. add some isopropyl alcohol to that mix I told you about.. etc. if it's clean on the other hand.. don't drain it just to drain it., though i might pull it to make sure the unlaoding valve moved freely and/ or clean it etc.

soundguy

 

[jonesnjones]

soundguy:
I have the oem crank driven off a 800. the oil is brand new since I just put new piston o rings unloading valve in it. at an idle I have to put about 350 lbs. on it. for it to stay down
I put universal hydraulic oil in it. this setup has been workin for. last 3 yrs. great
all at once it decided to do this. that's when I replaced what I have mentioned. thank you for your time. by the way if I were to sell it about what should I ask in working order and in moderate to great condition.

 

[Soundguy]

crank driven?

crank driven pump are onthe front of the tractor and are SUPER high volume. if you have that plumbed into your hyd system no wonder you can't keep the arms down... it's too much flow for the valve to dump.

now.. if we are instead talking about the side engine ( CAM ) driven pump.. then therein is still part of the problem. a pump from an 00/01 is 4gpm.. oem was 2.85 gpm. that's extra oil for that valve to dump when bypassing to sump.

I'd also still think the unloading valve is hanging or binding rather.. that or back pressure valve restricting oil.. only needs a few psi to keep unloader alive..

please clarify what pump you have.. cam or crank driven..

soundguy

 

[jonesnjones]

it is crank driven. has been working this way for about 3 yrs. just all of a sudden started doing this.

 

[Soundguy]

so you have a crank driven pump plumbed in in place of the oem engine side pump?

i'd like to see a pic.

what oil volume are you pushing. the unload valve isn't designed to dump more than about 3gpm.

i won't / can't comment any further untill there is full discolsure on the particulars of this non stock hyd system, and the bugs it has..

soundguy

 

[Jbrink64]

it is crank driven. has been working this way for about 3 yrs. just all of a sudden started doing this.

Sounds to me like a misunderstanding, re: pump placement. It was working in the past, something is now gone wrong, now it's misbehaving.

 

[Soundguy]

can't comment further without know full details of the hyd system as he doesn't have it setup as oem... could be anything right now.... gum on his shoe on a tuesday.. that kind of thing. guessing at this point is useless with a non oem system without knowing exactly how it is plumbed.. type of pump.. any diverters, restrictors, priority valves, PB.. etc. inthe system and how he has it plumbed to the oem system.. ie, as a repalcement or in tandem.. etc.. etc..

pics nad description will be needed.

soundguy

 

[Soundguy]

Sounds to me like a misunderstanding, re: pump placement. It was working in the past, something is now gone wrong, now it's misbehaving.

no misunderstanding on my part.. he has dramatically changed the oem hyd setup on that tractor now needs help with it.. before he can get htat help.. he needs to tell us exactly what he has and how it is plumbed...

soundguy