O-Ring for Unloading Valve

[BWARD]

I am working on my 641 hydraulics. I have replaced all the o-rings in the top cover. I am trying to find the proper rubber o-ring for the unloading valve. CNH dealer says that the unloading valve for my '62 641 should have a metal snap ring that works like a piston ring which lists at $28.00. The rubber o-ring I need is no longer available and I must update to the newer unloading valve which lists at $120.00. The NAA rubber unloading valve o-rings are available in lots of 4 for $23.00. Does anyone know if the NAA rubber o-ring will work on my 641 or have a source for the proper o-ring that I need?

 

[Bob]

ANY good hydraulic shop should be able to fix you up with an "O" ring... they are pretty generic.

 

[murn ga]

Computers are wonderful most of the time,but they seem to get these kids behind the counter in trouble alot of times. I cannot believe N.H. would drop an o"ring that is used other places. Call N.H. dealer back and ask them to punch in the old Ford number for the o"ring NCA836B.I think it was the same for NAA,but it would only be around a 1.00 each.

 

[Bob]

Take a look at the thread linked below. Make sense?
replacment

 

[john in la]

No offence to Bern but........
No that post does not make sense to me.

New Holland still shows part # NCA836B as a good # and cost #1.81

Part # 9626944 may be a replacement for the above part because it is a Case # but the cost is $1.07

The question I got to ask is.........
If these are the same parts why do they cost different prices; and why did they just not supersede the original part to the new #.

Messick’s shows they have both parts in stock. They have 12 of one kind and 8 of the other kind showing me they do not interchange.

 

[RickB]

But I am a big fan of the piston ring style unload valve seal. I believe they are less prone to sticking than an o-ring in situations where tractors sit idle for long periods. And stuck unload valves are one of the most common causes of inoperative 3pt hitches on Fords.

 

[BWARD]

Thanks to all for your input. CNH dealer told me that since my 641 is a 1962 model, I must use the snap ring part #C9NNH893A (start year 1955) and snap ring type unload valve. The o-ring part #NCA836B (start year 1953) will not work in my tractor since it was built after 1955 and someone put the wrong unload valve in. Seems to me that they are trying to move as many parts as possible. My problem is that the hydraulics hiccup once about every 30 seconds. Thanks again.

 

[john in la]

Ask your dealer to explane this excerpt from a 1959 Ford parts book; if the o-ring was not used past 1955.

You can see the NAA used a differant unload valve from the 600/601/2000 but the o-ring was the same part.

Just tell him you want part # NCA 836 B and if it is wrong you still want it. If he still gives you any grief just order it online from Messick's. They have them in stock and ready to ship.

The reason your dealer is saying this is because New Holland superseded the old part with the new valve and metal ring so he can not even see the old parts unless he brakes out the old paper parts book. The old unload valve is NLA but the o-ring is if you know what part # to ask for.

 

[Bern]

No offense taken. That last post was 10 years ago (and I do remember it quite well). Evidently at that time, the NCA number was no good and superceded. For whatever reason, it is good now. The 962.... number is not a Case number.

The important thing is that this guy does not spend $100 plus dollars when he can fix this for $1.38

 

[Tony Jacobs]

Hello Bob , Absolutely not there are certain o-ring's the Ford uses like the unloading o-ring that ARE NOT A STANDARD SIZE AND WILL NOT WORK unless you you use Ford's size o-ring . Most Ford o-ring's are standard but thre are a few special ones. Thanks Tony