One more time...

[marrt]

Ok, let's talk UTF once again. At least for the Bondioli & Pavesi NT10 pump used in the 425. This pump is optimized for a hydraulic viscosity range of 15 - 35 cSt (mm2/s). Of course, you cannot talk about viscosity without talking about the associated temperature. Most viscosity ratings are given at 40C and 100C. Our "normal" operating temperature is probably something closer to 150F (that's a guess... I need to measure it) or roughly 65C. So, for simplicity, let's choose a midpoint between 40C and 100C, or 70C. Also, the change in viscosity between two different temperatures is not perfectly linear, but probably close enough for this exercise.

Now, take a look at this table (Viscosity Charts - Bob is the Oil Guy - Bob is the Oil Guy). Let's assume we are going for the mid-point range for the pump, or 25 cSt. At 70C, the target cSt is 17.5 for a SAE right between 40 weight and 50 weight engine oil. Even the maximum recommendation of 35 cSt is well within range of 50 weight engine oil.
What does all this mean?

1. The guys at Power Trac probably know what they are doing specifying a multi-weight engine oil. If this was an application in a temperature controlled factory, then you could easily specify a fixed weight hydraulic oil. However, because Power Trac's must be able to function in low temperature conditions, a multi-weight oil is required.

2. Using a standard ISO hydraulic oil or even a Universal Tractor Fluid hydraulic oil (with the usual narrow viscosity range of 10w-20 or so) will probably not work well for a Power Trac. These oils would be too thin to stay with the optimized viscosity range for the NT10 when the tractor is "warmed up" while still being able to allow the tractor to start at freezing temps. This is unfortunate because these oils have many superior characteristics when used in a hydraulic application.

3. Changing to wide range synthetic motor oil such as a 10w-50 would appear to offer the best option to hit the target viscosity range for the NT10. However, the wider the viscosity range, the poorer the sheer characteristics over time. Therefore, Power Trac's choice of 10w-40 makes a lot of sense for dino oils.

 

[cqaigy2]

I think even i was able to follow that.

Thanks!

 

[Gale Hawkins]

We find UTF does seem to shear over time and using Lucas Hydraulic Oil Booster and stop leaks helps restore the function. Not a Lucas user but for this one product after a neighbor got me to try it and it worked well.

 

[cqaigy2]

So the Lucas Hydraulic Oil Booster improve the viscosity and shear stability of the UTF?

 

[marrt]

Hmm...this Lucas Oil Booster looks interesting. At the recommended dosage (10% - 20% of the hydraulic reservoir), it would significantly increase the overall viscosity. Further, they mention anti-foaming and anti-rust additives. Perhaps they have anti-wear additives too (e.g., Zinc).

I seem to recall CASE using motor oil in some of their equipment. They separately sold an additives package to improve performance.

 

[Gale Hawkins]

Amazon.com: Customer Reviews: Lucas Oil 10018 Hydraulic Oil Booster with Stop Leak. Gallon

It was Joe Andersen's 17 Jan 2013 review concerning his old road grader that was leaking 10 gallons a day dropped to 1/2 gallon per day on the second day.

My first dig this year was a large hole in the bank so the neighbor could get them to deliver his storm shelter. I was getting some serious dripping out of the stick cylinder and good seeps out of others on the hoe. Two-three years ago I changed the filters twice and changed out a couple times by accident and when back with Premium line from TSC but this spring it was doing some serious leaking.

As noted I was moving some dirt using the FEL and after it got hot I added most of the gallon jug then used it for another hour or so before starting to use the hoe to clear ground. There was no dripping when I started to use the hoe.

The hoe was not in used when I was hauling dirt for a quarter mile (made 8 round trips) so it could not have done much to swell seals in that short period of time. It did add some viscosity however. It is my 'guess' that shearing was a factor.

Basically I am anti Lucas but my welder (pasted recently from a heart attach) sold me on this Lucas product when he was rebuilding both buckets and mounted my thumb about three years. He had a Ford 555 was was a major leaker.

One gallon gave me about a 5% ratio and I was going to 10% but now I think we can work it hard this year. If it goes to leaking bad again I will just take it to the recommended 10% ratio with 20% being max usage.

Marrt I have heard of some companies that worked in mild climates used straight 30 weight motor oil. Having grown put used STP in our worn out engines I got away from its usage and had pigeon holed Lucas in the same box. I do not know about their other products I will buy more of this at $30 a gallon at TSC.

 

[ponytug]

Marrt,

This is some of the same data that I used to convince me that 10/15W50 synthetic was the way to go. In practice, I can't see any difference from the 10w40 DELO that came out, but we'll see. My worry about additives in the 14XX and 18XX series are the wet brakes.

Thanks for sharing. I really like Bob's data.

All the best,

Peter

Ok, let's talk UTF once again. At least for the Bondioli & Pavesi NT10 pump used in the 425. This pump is optimized for a hydraulic viscosity range of 15 - 35 cSt (mm2/s). Of course, you cannot talk about viscosity without talking about the associated temperature. Most viscosity ratings are given at 40C and 100C. Our "normal" operating temperature is probably something closer to 150F (that's a guess... I need to measure it) or roughly 65C. So, for simplicity, let's choose a midpoint between 40C and 100C, or 70C. Also, the change in viscosity between two different temperatures is not perfectly linear, but probably close enough for this exercise.

Now, take a look at this table (Viscosity Charts - Bob is the Oil Guy - Bob is the Oil Guy). Let's assume we are going for the mid-point range for the pump, or 25 cSt. At 70C, the target cSt is 17.5 for a SAE right between 40 weight and 50 weight engine oil. Even the maximum recommendation of 35 cSt is well within range of 50 weight engine oil.
What does all this mean?

1. The guys at Power Trac probably know what they are doing specifying a multi-weight engine oil. If this was an application in a temperature controlled factory, then you could easily specify a fixed weight hydraulic oil. However, because Power Trac's must be able to function in low temperature conditions, a multi-weight oil is required.

2. Using a standard ISO hydraulic oil or even a Universal Tractor Fluid hydraulic oil (with the usual narrow viscosity range of 10w-20 or so) will probably not work well for a Power Trac. These oils would be too thin to stay with the optimized viscosity range for the NT10 when the tractor is "warmed up" while still being able to allow the tractor to start at freezing temps. This is unfortunate because these oils have many superior characteristics when used in a hydraulic application.

3. Changing to wide range synthetic motor oil such as a 10w-50 would appear to offer the best option to hit the target viscosity range for the NT10. However, the wider the viscosity range, the poorer the sheer characteristics over time. Therefore, Power Trac's choice of 10w-40 makes a lot of sense for dino oils.