Can I upgrade my hydraulic pump?

[fatjay]

I have a strong running Oliver backhoe. It痴 a great matching but the hoe is a bit on the slow side. The hydraulic pump is mounted on the front and swapping should be fairly easy, I would like to find a higher flow pump to speed it up, especially when I move 2 cylinders at the same time. When I move one it痴 not quick but when I move 2 it almost doesn稚 move at all.

 

[mopardude318]

What kind of Oliver? Got a picture?

 

[fatjay]

It’s an Oliver 77 industrial, very old. The loader and hoe were made by Ware, and possibly the pump as well. I’ll see if I can get a picture in a bit but it’s driven by a pto shaft out of the front of the engine.

 

[fatjay]

 

[oldnslo]

A few things to consider when attempting to increase pump flow.

What is the displacement or flow of the pump you currently have?

1) inlet line size recommended max velocity in suction lines is 4 feet per second

2) valve size: will it handle higher flow without excessive pressure drop

3) will the tractors drive shaft handle The increased torque

4) reservoir, filter, relief, etc. will these work with increases flow?

 

[dfkrug]

That is a good project, if you are somewhat handy.

Since your Oliver is from 1953, I suspect the engine is powerful enough to handle a bigger pump, and possibly more pressure. You can make an adapter housing for a lot of new inexpensive pumps. 2 things to determine first are the rotation direction and the displacement. You can determine displacement by taking the pump apart and measuring, if you can not decode the maker mark. I would also upgrade the low-pressure fitting on your pump's outlet.

I have bought numerous good and inexpensive hyd pumps from SurplusCenter, and made them work. I would hesitate to buy anything used because often they are dirty or worn inside, and you just don't know in advance.

 

[ptsg]

If you can't figure out what displacement the original pump has, Surplus Center has a really nice calculator that helps you figure out the displacement.

Here is the link: Surplus Center

 

[ericm979]

Could there be restrictors in the valve stack or the connections to it? Or the pump is worn? It doesn't seem like a manufacturer would make it that way on purpose.

 

[fatjay]

All very good questions, to which i have almost no answers. The engine is out of a super 88, a strait 6 3.5 liter 55hp engine. I know many things about engines, just not about hydraluics aside from their basic principals of operation. My pump looks new on the inside though. Once upon a time I sheered all the splines out of the shaft. I drilled it and put a spring pin in it and it's been fine, except when i sheered it yesterday, but it was an easy fix.

 

[dfkrug]

Could there be restrictors in the valve stack or the connections to it? Or the pump is worn? It doesn't seem like a manufacturer would make it that way on purpose.

A lot of older tractors had plenty of power, but wimpy hyd pumps. OTOH, the B8200 is only 18-19hp, and its wimpy pump is all it can handle.