Hydraulic safety valve, problem solved

I solved my problem of my 2N "with heavy load on rear boom, locked up, unable to lower until cyclinder leaked down".
I replaced the NEW SAFETY VALVE, with an old one. The new one has "screw driver, preset on outer end", while the old one has a "cotter pin" to retain the spring, on outer end.

Wished I had pressure tested the new one (and old)

My theory is that the new safety valve exceeded the pressure specification and therefore the old control lever spring
(Between cylinder and forks), could not over come the spring specifications. This problem only showed up if I tried to pull fence post or electrical grounding rod or 500# 0n rear boom.

Lesson learned: Pressure test, before replacing safety valve.

Charles Krammin SW MI
 
(quoted from post at 14:51:12 06/08/16) I solved my problem of my 2N "with heavy load on rear boom, locked up, unable to lower until cyclinder leaked down".
I replaced the NEW SAFETY VALVE, with an old one. The new one has "screw driver, preset on outer end", while the old one has a "cotter pin" to retain the spring, on outer end.

Wished I had pressure tested the new one (and old)

My theory is that the new safety valve exceeded the pressure specification and therefore the old control lever spring
(Between cylinder and forks), could not over come the spring specifications. This problem only showed up if I tried to pull fence post or electrical grounding rod or 500# 0n rear boom.

Lesson learned: Pressure test, before replacing safety valve.

Charles Krammin SW MI

I guess you're meaning that you're supposed to set the pressure yourself before installing? Just how exactly are you supposed to do that?
 

Use John Smiths Safety/relief valve tester... :shock:

He did post a pix of his tester, I had made one its crude and leaked I never got around to refining it...

Not to be a smart aZZ its a good question...
 
Sounds like yet another symptom of a Chinese made, almost right part.

I bought a foreign made TISCO relief valve for my 860 several years that apparently would not relieve at any pressure as it blew the head gasket on the pump when I dead headed it to test.

Dean
 
(quoted from post at 21:29:29 06/08/16)
Use John Smiths Safety/relief valve tester... :shock:

He did post a pix of his tester, I had made one its crude and leaked I never got around to refining it...

.

I have never had to mess with a relief valve . I did make a crude tester from a t with a grease zerk after seeing Mr Smiths post .

Do they go bad often ? From stress or corrosions or just debris caught in the valve ? I would not want to pay for a part just to feel good but I don't want to sell my two extras N's with any time bombs aboard .
 

They are probably a one in a life time maintenance item... At least they are cheap :D They do deal with a harsh environment... They can be a bear to diagnosis So I install one if I have any doubts...
 
These are preset at the factory. Old original ones have a cotter pin in the outlet end. the new one had a screwdriver turned in to preset and then a pin in the center of the screwdriver slot.
The supplier said they will check some they have on hand. GGOODY No refund as it took me 3 years to figure it out.

Good news- Old pump turns out pressure. Put chain around lift arm and it bent links and almost broke chain, but relief valve "sounded off" (vibrate sound).

Charles Krammin

P thanks for the part Royce
 
You're welcome. It was nice to see you and the Mrs. again!
Hopefully we'll make it down to see you at the Charleston show again this year.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top