9N Hydraulics

[Plane Bart]

on my just completed 1940 9N, 6 volt I hooked the Squealer 600 Bush hog (545 Lbs) to it today and It will not lift
pulled inspection plate no leaks, levers are connceted to the rocker levers.
with no load on the lift arms when I opperate the lift it some times will come up slow and real jerkey and sometimes fast and jerkey
where do I start trouble shooting from here have some Ideas but you guys will know exactly where I shold start
Thanks

 

[Paul Baguley]

My system did the same thing. The large spring behind the seat did not have enough tension on it. It was not letting the relief valve close.I adjusted it per the FO-4 book and up it came. Been working great since.

 

[JMOR]

(quoted from post at 18:36:28 06/20/10) My system did the same thing. The large spring behind the seat did not have enough tension on it. It was not letting the relief valve close.I adjusted it per the FO-4 book and up it came. Been working great since.

he relief valve has no mechanical connection to any mechanism. It is simply a spring pressing a ball against a seat & when pressure is high enough the pressure will overcome the spring, lifting ball off seat and 'relieve' pressure into the reservoir.

 

[lha]

The reason most people[myself included]don't mess with the draft control spring is that the yoke and plunger are locked by rust and time.I've been working on mine off and on,mostly off.I used a tactic recommended by someone.I made up the gap with a large washer.Cut a slot and put it in between spring and guide,works temporarily,but needs to be fixed,maybe you will be lucky and it will not be frozen.---lha

 

[Plane Bart]

Spring should have nothing to do with with no equipment attached, I am thinking I have trash that I did not cleaned out but not sure if it is in the top cylinder or in the pump, you guys are saying the spring need to be adjusted?
I will check the F-04 tomorrow

 

[JMOR]

(quoted from post at 21:34:01 06/20/10) Spring should have nothing to do with with no equipment attached, I am thinking I have trash that I did not cleaned out but not sure if it is in the top cylinder or in the pump, you guys are saying the spring need to be adjusted?
I will check the F-04 tomorrow

didn't say that.

 

[Plane Bart]

Sorry If i possiably offended you.
Are you saying the relife valve is not functioning properly?
I am not exactly sure what you mean here.
I checked my main control spring and it has no end play, I am still looking for something to try to find out when there is nothing attached to the back of my tractor the lift arms come up slow and jerkey.

 

[JMOR]

No sir, you didn't offend me! I was just telling you that the relief valve has no mechanical connection to the draft control spring or any mechanism. There are other areas to explore. I think someone else suggested the draft control spring. Slow & jerky suggest that one or more of the 4 pump cylinders isn't functioning properly. But other possibilities exist, such as the intake control valve not opening completely, leaks somewhere in the system (about 9 possibilities), broken inlet or outlet valves or valve springs........

 

[Plane Bart]

Thank you Sir, they may have not been far off after studying over the F-04 I did realize that my newbie self put the top link bracket that connects to the draft control sring in upside down which may have something to do with it, I will fix that first the re-examine my original problem, but thank you fo rthe input I will also look into the relief valave and stuck valves.