Multi-Viscosity Hydraulic Oil

[drawthree]

Anyone have any thoughts on using multi-viscosity hydraulic oil in a 1 ton chinese mini-x? I fired mine up in 15 degree fahrenheit weather recently and the high pressure bypass valve sounded really angry until the oil warmed up. The only well known brand I've found offering it so far is Amsoil:

https://www.amsoil.com/p/amsoil-iso-46-100-synthetic-multi-viscosity-hydraulic-oil-hvi/

 

[bmaverick]

Anyone have any thoughts on using multi-viscosity hydraulic oil in a 1 ton chinese mini-x? I fired mine up in 15 degree fahrenheit weather recently and the high pressure bypass valve sounded really angry until the oil warmed up. The only well known brand I've found offering it so far is Amsoil:

https://www.amsoil.com/p/amsoil-iso-46-100-synthetic-multi-viscosity-hydraulic-oil-hvi/

Knowing the Chinese diesel engines are somewhat like Yanmar and Kubota, the Yanmars use TF500A (J20C) it's a synthetic multi-viscosity. In fact J20C is a John Deere spec. for Hy-Gard. And J20C is also CAT T0-2 for Caterpillar and Kubota UDT. Now, if you need the machine to work below 10F, there is the J20D for low viscosity as well. Most of these tractor hydraulic oils have 10W30 as it's base oil.

You can buy J20C as a store brand long as the jug states 'meets' J20C or 'meets' CAT T0-2.

 

[drawthree]

Thanks for all that information!

 

[oldnslo]

Was the noise you where hearing at start up with no functions operating or when trying to operate a function?

I believe Deere Hygard, Case IH hytran, Kubota UDT are all multigrade fluids but are not labeled like engine oils.

 

[drawthree]

Was the noise you where hearing at start up with no functions operating or when trying to operate a function?

I believe Deere Hygard, Case IH hytran, Kubota UDT are all multigrade fluids but are not labeled like engine oils.

It was with no functions operating. It was really cold and I had the engine choked to keep it going until it warmed a little. If I killed the choke or raised the throttle it was dying out. I took a video of it and just uploaded it here:

 

[Advil]

Or Mobil Delvac Tractor Hydraulic Fluid. It's also J20C.

 

[oldnslo]

If this is a gear pump there should be minimal pressure with no functions active so I would suggest investing in a pressure gauge to monitor what the pressure is at start up.

My hearing is bad but cold starts can also cause pump to cavitate which is another reason to try and verify pressure.

 

[drawthree]

If this is a gear pump there should be minimal pressure with no functions active so I would suggest investing in a pressure gauge to monitor what the pressure is at start up.

My hearing is bad but cold starts can also cause pump to cavitate which is another reason to try and verify pressure.

I think it is a gear pump but I thought it would be high pressure all the time regardless of if there is a function active or not. My understanding of the system is that the pump is just direct drive from the engine and it is always pumping high pressure up to the manifold which is directly under/tied to the control sticks on my machine. Then on the manifold there is a high pressure bypass so when there are no functions active that valve will open when the pressure is high enough and allow the fluid to return to the tank.

The sound I was hearing seemed to be coming from the manifold so I thought what was happening was that with the engine running so slow the pressure was not constantly high enough for the bypass to be open all the time, but when it did get high enough I was thinking the noise was the cold fluid forcing its way past that bypass valve.

 

[oldnslo]

Draw3,
Yes the gear pump will be turning whenever the engine is running. the oil should flow freely from the pump through the system back to tank at minimal pressure With no functions being used.

Can you safely touch the lines from the pump to the valve or manifold? Same question for the return lines from the valve going to the filter, or cooler or reservoir.

If yes is one of return lines getting significantly faster than the others?

If yes that indicate where the flow is going and provide a little guidance on what the restriction is being caused by.