about 8N hydraulics?

[ron,ar]

I seem to remember someone posting that there is a pressure port somewhere on an 8N for hydraulic pressure. I think it also requires the lift arms being tied down. I need a temporary fluid supply and don't remember where the pressure port is, if there is one at all. Thanks for any help in advance.

 

[ron,ar]

I found out what I needed in the archieves, thanks anyway folks.

 

[lonestarjeff]

That pressure port is down by your right heal, in the pump's base plate. Whatcha using it for?

Jeff

 

[TxAllisMan]

I would like to see what he is going to use it for also.

 

[TheOldHokie]

Note that port is a 1/2-20 UNF thread. An SAE o-ring boss style adapter is needed - NOT AN NPT PIPE FITTING!

TOH

 

[souNdguy]

Is the port actually countersunk for the ORB... or are you just mashing the cr@p out of it to get it to seal. Seels like one of those orings that has the metal backing to prevent the oring crum blowing out would be a good addition.. if there is no milled boss. ?? Or was it made for some kind of banjo fitting with a soft copper sealing washer?

Soundguy

 

[ZANE]

No the O ring type fitting should not be used. There is no place for the O ring to go. It requires a washer of either copper like the original or a nylon one like from a drain plug on an oil pan. I have not found a ready made fitting that has the correct thread size. I have searched all the suppliers and manufactures of hydraulic fittings and found none. It might be possible to use a nearly right threaded fitting but I would not want to chance ruining the test port threads of the pump. I make a fitting by using a grade five bolt of the correct thread size and drill the center of the bolt out. then I silver solder half a 3/8" pipe coupling to the head of the bolt. I use a Nylon washer for a drain plug and it works good. It is necessary to bend the rear muffler/exhaust bracket outwards some to make clearance for the fitting.

Zane

 

[souNdguy]

That's what i figured.. soft copper washer.. or some sort of washer that can't blow out easilly.. like a metal ringed one.. or the nylon one you mention. I've never had sucess using an ORB fitting in a place not specifically countersunk for it...

Soundguy

 

[TheOldHokie]

Works for me. If you don't like the o-ring take it off and replace with your washer. The SAE ORB fitting is the correct thread.

TOH

 

[TheOldHokie]

There is a small countersink but it's not a "real" ORB port which is a lot more complicated than a plain counterbore. I use an adjustable (jam nut with washer)ORB fitting and I don't overtighten the jam nut. Works fine. The spotfaceed area on my 9N was so buggered up I doubt a copper washer would be any more effective but you could easily replace the o-ring with one if you'd prefer.

TOH

 

[souNdguy]

The threading would just be non taper thread like bolt thread then.. that's why the orb fitting fits then. If there is some counter bore or couter sink.. then i can see why the orb fitting works.. it must be just enough counter bore so the oring is getting mashed into it pretty good.

Hmm..I f the face was good.. I'd be tempted to use a crusheing copepr washer... but I'm also a fan of 'easy' and if it works.. it works.. no need to muck up something that works even if it ain't 100% right. As I mentioned I have seen ORB fittings used with an oring that was bonded to the ID of a washer and the washer helped keet the oring from bloting out.. even though there was no counter bore present..

Soundguy

 

[TheOldHokie]

Exactly - it is an SAE 1/2-20 thread. The drilled hole was chamfered for the tapping operation and the remaining countersink is just enough let the o-ring recess slightly. Not perfect or to the SAE standard but more than sufficient to seal the 1500 PSI or so coming through the helix of the thread. I considered cutting a counterbore for the o-ring but "if it ain't broke don't fix it". Of course you could always get an SAE port cutter and make it a "real" SAE-6 (9/16") port good to 4000 PSI. Last I looked they ran about $200+.

The other setup you mention is a back-up washer bonded to the fitting to provide a counterbore for the o-ring. I believe it is some ISO or European standard and I think the thread is BSPP or metric. I can check the Parker book if you want the specifics but I don't believe you'll find one with the proper thread.

TOH

 

[TheOldHokie]

Looked it up - the spotface/backup washer setup is ISO 1179-x and has a bunch of variants - one of which is the captive o-ring form - but alas - BSPP threads. Parker claims they developed it to allow Komatsu (K4) and Japanese (JIS) 60* flare fittings to be used as port adapters. BSPP does include a 1/2-14 thread spec so maybe one of the ISO 1179-2 sealing washers would work on the SAE ORB (J1926) fittings. Certainly more sealing power than this application requires assuming the spotface isn't dinged.

TOH