Howdy, Just bought a 76 3c mkIII jcb backhoe

[chris_davis]

Howdy all, my name is Chris and I live in Texas, states.
Great forum.
I bought a jcb backhoe about a week ago, managed to move it so far and change the oil.
But so far that's about it, work is kickin my butt.
It's one neat backhoe. It's built like a tank compared to the new ones. So far it appears it has a Leyland 4.98 motor and I haven't had a chance to figure out the exact transmission yet. It also appears that it uses mostly heavy duty grade/light motor oils for most of the lubricants. Which isn't that odd, most of the farm equipment from 50's-60's seemed to use oil as the lubricants. Have a manual for it but mostly specs mobil oils that haven't been made for 20 years. It was painted couple years ago and I have managed to straighten out some dings and touch up some paint here and there. Replaced some grease zerks on it and started greasing it yesterday. Was sad to see that almost all the zerks had paint covering them and just touching it with the nozzle knocked off the paint. So obviously this old boy hasn't been serviced or maintenanced for years. I am running it only to adjust access to different parts, till I can get all the fluids changed and get it fully serviced.
I could use some help on identifying the torque converter/transmission and what filter it uses. Thanks to Mark for providing those part numbers. I'm trying to cross it over to something I can get but no luck so far.
Attached is a picture sorry it's so bad, I was in a hurry and didn't look at the picture till later, when I figured out my lense was dirty.
I'll get some more soon.

[derby]

I can't help with your Maintenance issues, but nice machine!

[Jeremy Rowland]

Hi and welcome Chris I am sure somebody on here can point you in the right direction; hope that you enjoy this forum.

Jeremy

[TullyveeryClassicJCB]

That's a nice hoe you have there!

[chris_davis]

Hey thanks for the compliments.
I think I have narrowed it down. The torque converter calls for the same oil as the engine and the filter canisters appear to be the same.
I still have the old oil filter so when I pull the torque converter filter I will compare but fairly sure it's the same. The hydraulic oil they were using is a universal 303 so I think it will be ok. My gear box oil was milky which is bad, got water in it. Any ideas on reconditioning without pulling it all apart would be appreciated.
I have all my filters ordered and most of my oils. Will start changing them out tomorrow. Try to get some better pictures.
Get all this lubrication done and I can start working on brakes, since being able to stop is a nice bonus in my book.
Chris

[essexpete]

Are you sure the torque convertor uses the same as the engine? I would have thought a dedicated ATF/convertor oil would be more the order of day. Hydraulic ought to be hydraulic and perhaps a UTTO in the gearbox. Is the gearbox and back axle all one for oil on the Leyland skid?

[chris_davis]

I am fairly sure Essexpete, on the torque convertor, it wasn't uncommon even in to the late 70's. ATF's are actually a new oil considering, they don't really get released till the 80's, and were needed because vehicles ran with a higher normal temp.
I could probably switch out to an atf, if I could find a non detergent, non foam one that had light weight, since it's a sling send and has no pump.
My bad on the gearbox I never mentioned it's speced for an hd 90 weight, and usually the rear end is the same.
It does appear to be all one for oil, the manual is showing that I should drain the box and both the nuts on left and right of the axle next to the brakes. Has me kind of worried about adjusting brakes, which are basicly non working at this time.
Could use any advice I did try a little adjusting and still not acceptable on the brakes. I haven't figured out yet if this is wet or dry brakes.

[essexpete]

Dry brakes which are always a bit questionable. Someone here may be able to help. They may not be completely worn out but the internal mechanisms, so I understand, can become caked up with brake dust and stop the ramp effect working properly. They can be ineffective and suddenly grab. The parking brake on our old Sanderson is a similar design. The Leyland/Nuffield tractor forum might be of help to you as well.

[plessey]

Hi Chris
I had a 1979 jcb3 mk111 , she was torch and had a 4 speed transmission , there was a lever near the steering wheel that you could move either forward or back in any gear ,,, the oil I put in it was atf in the torch and 90 gear oil in the rear axle
,,, the brakes were dry brakes and you had to lift the floor of the cab to replace them, the brake system is a little odd in that there is discs inside a autuator which stuck a lot due to dust and also there was big ball bearings that ran on tapered slots that applyed pressure on the discs to apply the brakes ,, if the discs are worn out they are useless and can even stick ,,, it wasn't recommendedat the time but when I changed mine I lightly greased the ball bearings to keep them free ,,, if you are a heavy user of brakes dot do this because the dust will stick badly to the grease !!! But to be fair these machines don't go that fast !!! Built like a tank though and has huge digging and pushing power,,, had mine for 15 years and I never had a lot of problems ,, great digger,,,,

[chris_davis]

Wow thanks Essexpete and Plessey, really good info.
I haven't done a thing since last post. A cold front came throu and it got down to freezing. Then ofcourse Thanksgiving.
Heading out today to start on it.
Really good info on the brakes and how to get to them.
Thanks,
Chris