I have a 977L (48J) I want to put on a brush grapple on my cat and need to install a 3rd valve, if anyone has any leads on where to find the parts I would highly appreciate it. Or if someone has idea’s to control the hyd. Rams on the grapple someway else by adding a pump or plumbing into the hyd system and using a remote valve Thanks
From what I can determine from the parts book the hydraulic control units came in two and four valve configurations. I don't see any way to conveniently add an external valve but I'd be the last to say it can't be done.
Just need to find used parts, has to be a lot of them rusting in the weeds But where ???
Try dismantled machines here.....check the K models as well. https://www.machinerytrader.com/lis...equipment/manufacturer/caterpillar/model/977l
Thanks Old Magnet I’ll start making calls today
you'll also need the hardlines on the h-frame(loader boom),the hyd rotating unions that go on the 'firewall' behind the instrum panel,and the hardlines from the hydraulic resv/valves to the hyd unions..best to find a parts machine and scavenge EVERYTHING you need..even that is getting harder to do as a lot of these 77's have gone to scrap.
May be easier and possibly cheaper to find an intact donor machine...
I guess you could just swop over the hydraulic tank that has the 3rd valve in it and then use adapter fittings underneath and rubber hyd hose to go from there out to the bucket or forks..just to find a 977 let alone, a 3rd valve 977 machine being parted is hard to do today..best of luck..
There is an 11K at Montreal Tractor Inc. That they seem to breaking for parts. It is a very unusual piece it is plumbed about every way from Sunday. and I couldn't even guess what it's task was... however it is plumbed down the boom to what looks like it may be a side dump bucket. There are 4 pics of it and a contact name and number. Found it at Machinery trader 977L Dismantled machines
if its got a side dump then you might have a chance.From the pics it looks as tho it has the 3-valve tank as well with some extra return lines dumping to the tank thru the outside inspection port..Custom cab,looks like a late model cab front welded to the back of the original 977 cab. Bet that was fun. Might be an old listing,I think I remember that offering and emailing them back on it to no avail. Lots of dealers have listings and many of them don't update them often from what Ive found,just too busy or just forget to with lots going on. Best of luck.
I wanted to do the same thing,add a top clamp to a fork carriage on my 977,which is a two valve machine.The loader hyd pump output is like 80GPM or so with 1-1/4" hose with a Code 61/62 flange output..you could intercept the flow from the main pump,use a flow divider to feed the Cat tank and loader valving on one side and also a satellite valve to run your outboard implements,with a appropriately sized relief valve and secondary return line back to the Cat hyd tank. You're talking BIG valves,not easy to find,or for cheap.This is what appears to be done with the 977 in the photos of the Montreal Tractor unit you saw.Whether or not they used a relief valve back to the Cat hyd tank in addition to the secondary return or not is to be seen.I've seen a couple machines set up like this for oilfield work many years ago with multi-spool valves next to the operators station and custom outboard tools for pipeline work..Pressure doubling could develop between systems and make for a catastrophe when used under load without the appropriate relief valve..For the easiest route just get a Cat tank with the factory valves in it and plumb it from there.Best of luck.