Safety relief valve.

[David mains]

The hydrolic lift has always bleed off a little.the book says if it bleeds off at a steady pace its either the safety relief valve or the control valve.my question what is the torque on the saftey relief valve?

 

[Sean in PA]

What model tractor are you asking about? And is it bleeding off while running or while it is sitting after being parked?

 

[showcrop]

I think that you are asking about what is usually referred to as the rear lift arms slowly lowering while sitting. If that is what you are asking it is usually the lift cylinder packing is worn out. This is very common. The book is in general about ten year old as opposed to 60 year old machines.

 

[David mains]

thank you very much that is what I need to look into bc it is bleeding off when I shut the tractor off.the book says if it bleeds off at a constant rate then its either a saftey valve or a check valve.the book and tractor are both old like me.

 

[David mains]

thank you for your post.the tractor is a 641 Ford workmaster.i raise the lift shut the tractor off.the lift bleeds off at a constant rate,the book says its either the saftey valve or the check valve.my question was,what are the foot pounds of torque needed to tighten the saftey valve.i asked the question bc I removed the saftey valve to look to see any problems and it seemed really lose.

 

[David mains]

some things I didn't tell you and didn't want to leave anything out.an old tractor mechanic helped me overhaul the Ford 641 workmaster.he went thru the hydrolic pump and the lift and maybe he didn't replace the bushings in the lift cylinder bc I know we put a new saftey relief in.thanks for your reply I will deffently check the bushings.

 

[showcrop]

I have never heard of a "safety relief valve on these old Fords. I believe that you may be referencing the unloader valve. Did you access it from a cover under the hydraulic housing?

 

[David mains]

(quoted from post at 04:14:20 10/02/22) its a safety valve accessed thru the accessory plate on the hydrolic lift cover.quoted straight from fo-20 shop manuel.so what should I torque the saftey valve?sorry for my blunders.it dosent say relief.

I have never heard of a "safety relief valve on these old Fords. I believe that you may be referencing the unloader valve. Did you access it from a cover under the hydraulic housing?

 

[Sean in PA]

I believe that you may be referencing the unloader valve. Did you access it from a cover under the hydraulic housing?

The valve that is accessed via the plate on the bottom of the hydraulics sump is called the Relief Valve, not the Unloader Valve. Here is the description from the parts site:


86512642
HYDRAULIC VALVE
Valve Assy., Hydraulic Pump Relief, Replaces NCA638C; (Prod Date) After 01-Jan-1955

 

[David mains]

(quoted from post at 17:26:54 10/02/22)

I believe that you may be referencing the unloader valve. Did you access it from a cover under the hydraulic housing?

The valve that is accessed via the plate on the bottom of the hydraulics sump is called the Relief Valve, not the Unloader Valve. Here is the description from the

86512642k
HYDRAULIC VALVE
Valve Assy., Hydraulic Pump Relief, Replaces NCA638C; (Prod Date) After 01-Jan-1955

im sorry maybe I have confused everyone.the ford FO-20 repair manuel says raise the lift and shut the tractor off if it bleeds off at a steady pace then its the saftey valve.if you replace the saftey valve and repete the process then its the check valve so I removed the saftey valve which is under the accessory plate on the hydrolic lift cover.so my question what is the foot pounds of torque needed to seat the saftey valve?

 

[JMOR]

(quoted from post at 21:35:15 10/02/22)

(quoted from post at 17:26:54 10/02/22)

I believe that you may be referencing the unloader valve. Did you access it from a cover under the hydraulic housing?

The valve that is accessed via the plate on the bottom of the hydraulics sump is called the Relief Valve, not the Unloader Valve. Here is the description from the

86512642k
HYDRAULIC VALVE
Valve Assy., Hydraulic Pump Relief, Replaces NCA638C; (Prod Date) After 01-Jan-1955

im sorry maybe I have confused everyone.the ford FO-20 repair manuel says raise the lift and shut the tractor off if it bleeds off at a steady pace then its the saftey valve.if you replace the saftey valve and repete the process then its the check valve so I removed the saftey valve which is under the accessory plate on the hydrolic lift cover.so my question what is the foot pounds of torque needed to seat the safety valve?

ever seen a torque spec on that. Clarification: there are two pressure relief valves, 1) relief valve for pump, found in bottom of sump, and 2) ram cylinder safety valve found under accessory plate.

 

[David mains]

(quoted from post at 11:01:40 10/03/22)

(quoted from post at 21:35:15 10/02/22)

(quoted from post at 17:26:54 10/02/22)

I believe that you may be referencing the unloader valve. Did you access it from a cover under the hydraulic housing?

The valve that is accessed via the plate on the bottom of the hydraulics sump is called the Relief Valve, not the Unloader Valve. Here is the description from the

86512642k
HYDRAULIC VALVE
Valve Assy., Hydraulic Pump Relief, Replaces NCA638C; (Prod Date) After 01-Jan-1955

im sorry maybe I have confused everyone.the ford FO-20 repair manuel says raise the lift and shut the tractor off if it bleeds off at a steady pace then its the saftey valve.if you replace the saftey valve and repete the process then its the check valve so I removed the saftey valve which is under the accessory plate on the hydrolic lift cover.so my question what is the foot pounds of torque needed to seat the safety valve?

ever seen a torque spec on that. Clarification: there are two pressure relief valves, 1) relief valve for pump, found in bottom of sump, and 2) ram cylinder safety valve found under accessory plate.

? What do you torque the ram cylinder saftey valve in ft/pounds.

 

[JMOR]

Never seen torque specs on either. Doubt such exist. Maybe someone will show me wrong?