Ford 1700 Hydraulic Question

[square1]

I can't help noticing the "patina" on the spool valve and some other parts. It looks like there was water in there at one time and it sat for some time. What are the chances the spools / cylinders / pistons inside the valve are equally gunked up / corroded? Would soaking that whole assembly in some good parts cleaner and flushing it repeatedly with diesel or some solvent while gently working the input arm possibly be a worthwhile undertaking?

 

[Lawman17]

Alright well I put it back together and did as you requested Jethro and fluid gushes from the relief but no movement from the 3pt nor fluid to the cylinder head. I'm thinking worst case scenario now. But any insight would be great. Square1 yeah I noticed that as well. I'm to the point that if it is the spool valve I think I might be better off selling the tractor as is with no hydros as a replacement spool is about $300 from what I see online before I sink too much money into her considering it was a $500 non running tractor before I bought it but would love to keep her and make her live again.

 

[JC-jetro]

I can't help noticing the "patina" on the spool valve and some other parts. It looks like there was water in there at one time and it sat for some time. What are the chances the spools / cylinders / pistons inside the valve are equally gunked up / corroded? Would soaking that whole assembly in some good parts cleaner and flushing it repeatedly with diesel or some solvent while gently working the input arm possibly be a worthwhile undertaking?

You're probably right as this thing might have been soaking rain outside, flooded and all things causing all the gunk along with lack of maintenance. I think soaking the whole thing with strong solvent is wrong as inside the spool there are several o-ring and such that that will be completely destroyed.

JC,

 

[JC-jetro]

Alright well I put it back together and did as you requested Jethro and fluid gushes from the relief but no movement from the 3pt nor fluid to the cylinder head. I'm thinking worst case scenario now. But any insight would be great. Square1 yeah I noticed that as well. I'm to the point that if it is the spool valve I think I might be better off selling the tractor as is with no hydros as a replacement spool is about $300 from what I see online before I sink too much money into her considering it was a $500 non running tractor before I bought it but would love to keep her and make her live again.

Ok so far so good. Now just tell me what you did you find when you take the nut off on relief device ? did you see spring and the poppet ( it is a conical valve against a very stiff spring) and perhaps some shims.

did you put the relief back on the tractor and then tried to see if any oil comes out of lift cover oil hole?

from there we move to the spool valve as it is the only thing left to investigate. I can dig up a diagram for it later. you'll need several oring and such that once you open and clean the valves and spool requires replacement. There are many components in the spool valve requires very carefull disassembly and assembly after ward.

Jc,

 

[Lawman17]

Can you at least give me an idea of what a running 1700 with brand new front tires would be worth? I hate to sell but just don't see the worth in the investment. Thanks jethro for your help

 

[Lawman17]

Yeah found the spring 3 shims and the valve inside a sleeve. All cleaned and back together but still no fluid to the cylinder head. Scared to tear into anything as delicate as the spool valve but we will see

 

[JC-jetro]

Yeah found the spring 3 shims and the valve inside a sleeve. All cleaned and back together but still no fluid to the cylinder head. Scared to tear into anything as delicate as the spool valve but we will see

well,can't hurt it anymore, from where you are anything you do is in positive direction. since you managed to do what you have done and put back I see tacking the spool overhaul is doable. Might try a $10 package of assorted o-ring from HF and give it a go. I bought mine in pretty good shape relatively for about $3100.

did you say you buy it for $500 ? it is worth that much for scarp metal. imagine that your HYD pump is working and the salvage value of that is several hundred dollars for one part only.

JC,

 

[Lawman17]

Well I'm gonna consider tearing into it but check with a place here in town that works on hydraulics and see if they can rebuild it without charging an arm and a leg. Out of curiosity would you know of a schematic on the valve itself? I have a full manual but it doesn't break it down more than being a unit itself.

 

[JC-jetro]

Well I'm gonna consider tearing into it but check with a place here in town that works on hydraulics and see if they can rebuild it without charging an arm and a leg. Out of curiosity would you know of a schematic on the valve itself? I have a full manual but it doesn't break it down more than being a unit itself.

Yep, here you go. I also added lift arm cover and it's system. If you do it please take good close up pictures for future reference as I have not done that particular job myself. Consider lift control as a distribution for hyd oil with different porting and passage way. Pump flow constant and pressure is regulated by stiffness of main relief device downstream of main positive displacement gear type pump with variable flow based on RPM. Once you use pressurized oil to fill a cavity (piston, PSIxarea =lbf) then the rest of oil has to be diverted some where(diffy) or the pump would destroy itself or relief has to open. The setting of the relief is higher than lift system need. In your case I guess some o-ring is damaged, or a port is blocked causing the oil to be diverted to diffy and not where you need it. By process of elimination we gone from your pump to lift control valve so I reckon issue is at the lift control valve.

JC,

 

[trmechapt]

I just took the valve assy. off a 1710 this eve. It looks just like the same valve that is on the 1700. I have not checked on the parts site yet to verify. I have the same problem on this one that I'm working on for a friend. It has been awhile since I've had a 1700 hyd. system apart. The problem is in the valve somewhere; stuck unload valve etc. I will have to look in a repair manual to be sure. I will let you know when I find out.
Gary