Case 580c backhoe control valve ( dipper ). Top view, the flange that sits below the wiper seal. There is an o-ring below the chipped flange ( 0-ring not shown ). Anyone else have any experience with this? ( chip was caused by user error while replacing o-rings and seals ). Not pointing any fingers......:Banghead :Banghead :Banghead I feel bad enough.
That's not good. A lot depends on if the chamber below the O ring sees working pressure or if it is connected to tank. If it's just tank pressure, you may get away with installing the wiper seal upside down, but then it won't keep the dirt out like it should. Judgement call. If it's a pressure chamber then you're going to have to replace it or fix it. If I had to fix that I would probably mill out the top of the valve section and machine an insert to reclaim the counterbore.
valve chip No it's not looking to good but have seen some bush fixes in that area before. That section is around 1200.00 new plus o rings and time to pull it and install, starts adding up quick. Like Cmark said have seen them machined with a sleeve before. You can sometimes take a washer that fits the o ring grove and cut it in 1/3, slip it in the grove, with the cast clean mix a epoxy cup and build the top up in the damaged area. Work the bore area the wiper seal seats in, remove the 1/3 washer from the grove. Install the o ring in the grove, put some red loctite on the wiper seal bore and install the seal. The only way to really fix this is a section replacement new or used. Me, on the farm or homestead i would do a bush fix if needed. If doing contract, commercial work i would fix it correct
Thanks for the info. Gives me some more things to ask at the hydraulic shop. The guy there suggested a different O-ring. This thing is square shaped, a but more thick and he said it will be tricky getting it in the groove ( its almost like a washer ). Heck, for a buck - might as well give it a whirl. I married up the backhoe to the tractor today and gave it a run - as predicted, the valve at the top started to leak. Also found a leak at a weld on the swing hydraulic cylinder - a pin hole in the weld where the hoses meet up on the side near the piston. I get these two things fixed, and I should be home free.
A quad ring (kinda square cross section) would be a good idea, and assuming the pressure stays low may last a long time.
I ended up taking the valve section out. I did it while on the tractor - and it was a chore!!! Almost like a rubiks cube trying to get it out. I am not sure removing the entire 95 pound assembly would have been any easier, as the hoses just on the dipper valve were locked on megatight and took everything I had just to loosen them. The hoses for the boom would not unscrew - but I got over that. Hopefully I can either get this repaired, or get a used one to shove in its place. Either way, now I can take it places or just have an easier time fixing it.
All is back in place and working well. Putting it back together while on the machine went easier than taking it off. Id say a good hour or so. I do not envy doing it again tho. Anyone ever mess with switching over to quick connect couplers for the hoses that attach to the valves? Seems like in the long run it would be easier to deal with. ( or would that create another area of failure? )
Glad you got it back up and running, no on the quick connects, most machines will go 5-20 years with no repair in that area. If you have the correct crowfoot wrench it goes a lot better.