hydraulics stalling engine

Mustache · Feb 3, 2015

Hi everyone, my Massey Ferguson 1560 has a problem where the hydraulics stalling the engine.

To be more precise, running the PTO will stall the engine after a while if it runs without load and the fluid gets hot. Front loader hydraulics will stall the engine as well. After the hydraulic fluid gets hot enough, I can't even drive it any more than 10 feet or the engine stalls as well.

Just before this issue started I got a new snowblower with 2 hydraulic functions. Well, an old blower, so I am wondering if dirt in the lines may have screwed up the pump? I already changed the hydraulic fluid and filter (not many metal pieces on the filter magnets, so no issues there I think).

I wonder if its worth it taking the pump off / apart (I have to learn this first) or am I completely off track here?

Any advice appreciated!
Thanks folks!

J_J · Feb 3, 2015

Check your relief pressure with a hyd gauge.

Mustache · Feb 4, 2015

Not sure how to do that or even where to get the gage. Regardless of that, what should the gage read and depending on that, what could be wrong with it?
Thank you!

jix · Feb 4, 2015

I wonder if you have a dead-headed hydraulic circuit somewhere. That will make troubled for the pump, if so.

oosik · Feb 4, 2015

Exactly - a dead ended/completely blocked off hydraulic line and J_J's pressure gauge should show almost instant high pressure. In the absence of a pressure gauge - disconnect the lines used for the newly acquired snowblower and see if the problem is corrected. If it does - you have isolated the area of the problem.

Mustache · Feb 4, 2015

I did run it without the blower, but running the front loader. No PTO engaged either. I still had the same problem of the engine bogging down. Not sure if I said before that after a while even driving bogs down the engine. The hydraulic fluid is also the transmission fluid.

I'm reading through my service tech manual and there is only the main filter, no other screens. It technically could be any one of the valves too I guess? There are 2 outlets, 1 PTO valve, the loader valve and it looks like there is a shifter valve too. And of course main and sub pump.

I'm inclined to see if I can take the pump of and have it tested somewhere. If that's possible at all.

J_J · Feb 4, 2015

In open center hyd systems, with all valves in neutral, the pump flow passes through all valve to tank.

If your engine is stalling caused by the hyd, then you have something connected wrong. Perhaps your snow blower valve.

Are you sure all valves are in neutral?

Are all valves open center?

Xfaxman · Feb 4, 2015

Mustache said:
Not sure how to do that or even where to get the gage. Regardless of that, what should the gage read and depending on that, what could be wrong with it?
Thank you!

Here is one place, Surplus Center:
3000 PSI 2.5" LF LM GAUGE

kennyd · Feb 4, 2015

I don't think you have a pressure problem so a gauge won't help much, (and I sell them by the way) obviously the pump is creating enough pressure to eventually stall the engine.

What I belive you have is a flow problem, in that it's blocked. You say this started when you added a snowblower with two controls? My guess is that the valve on this blower might be closed center and its blocking the flow, causing the relief valve to open, and then overheat the fluid (that's probably burnt now and needs to be replaced when you get this issue sorted out)

Can you tell us more about this blower? Maybe show some pics of how its hooked up?