Nufield 425 / British Leyland 154 / BMC Mini 9/16

[KevinW]

I have a Nufield 425 (AKA: Leyland 154 and BMC Mini 9/16). Anyhow the hydraulics don't work properly. When you first start it up, the 3pt hitch will raise the implement. The more you use it and the warmer the tractor gets, the 3pt hitch won't raise. Is this a fluid issue or a hydraulic pump issue? The pump is on top of the engine and is belt driven. When hot and you flip the lever to raise the 3pt hitch, the engine just revs up real high and nothing happens.

http://angloamericanservices.com/leyland.html
http://www.newenglandtractor.com/usedtractor/leyland%20154%20info.htm

The Leyland 154 was the same as the Nuffield 4/25 apart from the change in color and three bars added to the front grill. In 1969 the retail price of the 154 De-lux was £680.

http://www.ytmag.com/articles/artint78.htm

Thanks,
Kevin

 

[mark777]

KevinW,

It sounds as though there might be a restriction in the return line, as in a filter, or filter screen partially clogged. Not positive on your model. When was the last time the filter and the hydraulic fluid was replaced? It may be that simple.

Generally, (IMO) belt or gear driven pumps either work or they don't . If it squeals loudly then it is a fluid flow problem, or plumbed wrong.

Good luck, Mark