Hydraulic Oil Leak
A few weeks ago I noticed a drop of oil on the top of the righthand track about half way along and below the hydraulic and diesel tanks. I kept on using the digger but noticed it was getting worse and when I took the side panels off, the steel plate below the tanks was wet with oil and it seemed to be coming from somewhere behind the counterweight where 4 hydraulics pipes pass through a bulkhead and into the engine bay. These pipes are all connected to the hydraulic tank. 3 are 1/4inch lines going to the side of the tank and one connecting into the large line between the cooler and the top of the tank. The leak was not continuous and seemed to stop after a while. Probably letting out about a cup full of oil. It was impossible to get into this area as the counterweight was in the way so had to come off.
A Web search showed someone using a pallet mover to do this, I tried to borrow one without success so I put an advert on Gumtree and got a secondhand one. The ground below the digger was just earth and stones so I built a timber platform below the digger to get a flat surface to work from. I also made up a few timbers to get the height I needed and then used packers to get the lifting points just right. There are 4 nuts to remove to free the counterweight and once done I lifted it about 10mm and withdrew it backward. It all went very easily and was a great way to get it off the machine. The machine didn't lift up at all when I took the weight off. Forgot to say I put the digger arm out at full stretch with the bucket on the ground and the blade hard down on the floor
So now for the inspection. Nothing obvious leaking so I started the engine and checked again. Still no obvious leak.
Anyway to cut a long story short, the pipes in this area are low pressure lines and get oil at certain times when the machine is working. So you have to move the rams and slew motor back and forward to get oil to go into these lines. Having done this, the oil leak became obvious and it was on the larger 3/8 inch hose where it took the bend through the bulkhead. So the hose needed replacing.
The tank end was easy enough to get to but the other end went behind the engine in a channel along with the 3 other smaller hoses and the 3 cable bundles associated with the engine, (fuel pump, stop relay, glow plugs etc) and reappeared behind the hydraulic pump and then disappeared again forward and underneath the seat.
Underneath the foot well plate (I remove the rubber mat, mine had been cut on the blade control side) and removed the 4 bolts that hold the plate down, The two speed switch wires were disconnected with care. This revealed a mass of cable bundles and hoses.
So at this point I called in help from Jack Swales Plant Services and Ryan came out the next day to help. He knew his stuff and within a hour we had the old hose out and a new one made up and fitted. With him waggling the hose and me inside the cab seeing what moved we worked out the hose went to the top of the slew motor. Once disconnected, he attached an electrical wire to the end in the cab so that we had something to pull the new hose through with. Pulling on the other end and helping it round bends it came out ok. A new one was made up in his van and then fed through whilst I pulled on the cable in the cab. A bit of waggling and help in places got it pulled through. Ryan said the fittings were BSP.
The old hose had several cracks running round the hose circumference where it bent through the bulkhead. The bending strain over 25 years had taken its toll.