What do you do when you encounter a rusty or corroded o-ring groove sealing surface like the one pictured (attached)?  Try to cram sand paper or brillo pad or Scotch Brite into the groove and move it around? Apply a sealant/gasket maker before the o-ring? Try to find a new fitting? Any advice appreciated.

I'm working on some hydraulic fluid leaks on our old ('65-ish) 922B wheel loader.

Thanks!

Several things I would suggest -
Do attempt to clean as much as you can, even with a hand wire brush, but be very cautious about damaging the surface that mates to the mountng block. These clearances must remain square between the two halves.

1. "O" rings come in various thickness and composition, be sure to use the correct ones.
2. Mating surfaces must have clean and square fit.
3. Tighten evenly.

I operated a SnowBlast Rotary Snow Plow, Hydraulic motor that ran upwards of 4000 psi. Blowing "O" rings was a problem until we figured out the clamping halves were not putting proper pressure on the hose to block, thus not properly compressing the "o" ring. Clearance is critical, especially when running such high pressures and volumes.
Someone else will chime in and offer more suggestions too.

In my opinion, no rubber "o" ring will support high pressures without the proper tight clearances to support it.
CTS

I use my hand held wire wheel and get inside the grooves as best I can. My personal experience has taught me to use only the heavy duty O rings Buna? from the dealer or a hydraulic shop. Do not use one from a generic kit, unless you really have to. JM

I've found small wire-wheels that chuck in my drill to be useful in cleaning O-ring grooves. For even smaller projects I've found tiny wire-wheels that fit my Dremel. It's a good thing they're cheap 'cause they don't last long!
Craig
   

James wrote:

What do you do when you encounter a rusty or corroded o-ring groove sealing surface like the one pictured (attached)?  Try to cram sand paper or brillo pad or Scotch Brite into the groove and move it around? Apply a sealant/gasket maker before the o-ring? Try to find a new fitting? Any advice appreciated.

I'm working on some hydraulic fluid leaks on our old ('65-ish) 922B wheel loader.

Thanks!

That flange didn't use an O-ring it used a metal back seal.
Since hard back seals aren't available now you need to get a D-ring seal  like Cat flange fittings use.
I drought that loader hyds go over 2000 PSI.
That old type hose and fittings are not for very high pressure so inspect then carefully.
Bob

you can get new fittings they are sae code 61. just be aware if you get new genuine fittings from the dealer the flange thickness is slightly more on the fittings made today for cat than the originals and what every one else makes today. so a spacer may be required if new genuine clamp plates are used with old or after market fittings.(this is more a issue with the more modern machines than the 1950 and 60s era gear. i dont know when they changed to using the thicker flanges)

the hose to use sae 100r2 spiral wire hose. if you reuse the older style fittings which have the bolt on hose clamp fit new grade 8 high tensile unf bolts. its also a good idea to replace the bolts that mount the fittings to the machine too.

and yes the seals are a d shape get them from the dealer or a hydraulics service.

to size hose seals and fittings remember they increase by 1 dash size, a dash is equivalent to a 16th of a inch for example 1/2 inch hose and fittings are dash-8 and 3/4 is dash-12