Lift Problems

Ok here is my problem. when I try to raise my lift it is very weak I have to give it a lot of gas to raise a 4 foot bush hog off the ground.I have checked the linkage to the pump it moves it in and out good. it is full of fluid. and I forgot to mention when I let off the gas it will drop back down even with the lever in the up position. any info would be greatly appreciated. It is a TO30.

Hello,

Your problem is not too bad to fix. It is simply a leak somewhere.

If this problem has come over time my first bet would be very worn piston rings. If it came rather suddenly I would say it is a gasket leak.
In worst case it can be a broken hydraulic cylinder.

In both cases you need to remove something, but I suggest you find a small mirror first, and a torch.

Hang something in the 3 point linkage, such that you need to use more than idle to lift it.

Open the inspection cover on the right side of the tractor, but first tilt the tractor over to the left side so the oil level gets under the inspection cover. (the cover with the transmission dip stick in)

When you have it open, you start the engine, and try to lift the implement. Then you hold the mirror just inside the hole, and use the torch to give you some light. Direct the mirror so you see up to the hydraulic cylinder that is on the underside of the hydraulic cover, (under the seat), and see if some hydraulic oil comes out the end of the cylinder. Then you turn the mirror so you can see the rest of the cylinder to see if it is cracked, and oil coming out of the crack.

Then you have to check the gasket between the hydraulic sylinder and the hydraulic cover. You will see 4 nuts under the seat, on top of the hydraulic cover, (not the ones holding the cover in place) and between the 2 nuts in front of the hydraulic cover there is a gasket (on the underside of the cover) and you will see if the oil come out between the cover and the sylinder when you hold the mirror checking the cylinder itself.

After this you have to turn the mirror so you can see in front of the hydraulic cover on the right side of the tractor. There is 2 plugs on the hydraulic cover on each side. On the right side of the tractor just under the plug there is a pipe going down to the pump (in the casting), and on the inside you can see if there is streaming out oil. That is the second place a gasket can be blown out and cause that big leak.

If you see no oil coming out on the place I have mentioned, there is only one more place it can be a leak, and that is the gasket between the pump and the centerhousing. You can not see this leak as it will leak into the oil, and I can not imagine you will see this, unless the rear end is almost empty for oil, and you have the engine running at top rpm and the implement is too heavy to lift. Maybe you can see a stream into the oil then.... But, there is no other place it can leak as far as I can see... unless you have a crack in the pipe I mentioned earlier or a crack in the pumphousing somewhere.

If it is a gasket leak, the repair will be cheap. If it is piston rings it will be a little more expensive, but not too bad.

If it is piston rings, remember to hone the cylinder, either with a hone, or abrasive cloth on a cardboard roll on a steel pin you can turn with your drill. Once honed and new rings, you will have very little drop in your link arms.

Let us hope it is no cracks somewhere, because that is a more expensive fix.

Will be nice if you come back with the solution so we can hear what it was.


Bill

Thanks Bill for the info. Good thing I didnt tear it down yet. I will let you know what I have found. Thanks

Well Bill I looked for the leaks on in inside with the mirror,and didnt find any so I tore it down. what I found was the rings in the jack had deep gashes in them.so I honed the cylinder and put new rings in. next I took a look at the pump it pretty scared up around the brass bushings so I ordered a rebuild kit and rebuilt it. It was a pretty simple task all the parts were just heavy for one person to move around. after I got it back together I filled it with GL-1 90W oil and it worked like a new. Like I said it was pretty simple. I didnt need a book just payed attention to how I took it apart and put it back together the same way I took it apart. but as for as the pump I think it was the pressure valve leaking. anyway thanks for all the info this is a great web site.