I believe everyone should do this to know how hot your hyd oil is.

[m5040]

Since we have a new PT180 owner on the site I would like to bring up a topic that all of us could benefit from. I have mentioned it before but I think it is important, so here it goes again. The Power Trac tractor uses hydraulics to do a lot of things and each feature generates heat especially hyd drive implements. How do you know how hot your hydraulic oil is? How hot is too hot?
Hydraulic fluid temperatures above 180 DEG F damage most seal compounds and accelerate degradation of the oil. While the operation of any hydraulic system at temperatures above 180 DEG F should be avoided, fluid temperature is too high when viscosity falls below the optimum value for the hydraulic system's components. This can occur well below 180 deg F, depending on the fluid's viscosity grade.
It is probably obvious that you should drill, tap and install a gauge. But that is kind of difficult, so most owners wont do it. So I just ordered one of these for my 2nd tractor off of fleebay

BAKER INSTRUMENTS 312FC Thermometer,Magnetic Surface,F/C | eBay

If the link gets old, it is just a magnetic surface temperature gauge (0-250 deg F) that can be applied to your hyd reservoir at/below oil level for most accurate results. For $25 and no labor you can know how close you get to overheating your oil.
Be careful because if on the lower portion of tractor in heavy brush it might get knocked loose, I have almost lost mine (cracked glass). Since then I just stick it to the LOADER CONTROL VALVE, this has continuous oil flow through it but might register a slightly lower reading. You can see it from a normal seating position.
I STARTED OFF WITH A NEW PT180 OWNER BECAUSE IT IS THE ONLY PT MADE WITHOUT A OIL COOLER! AND IT WILL OVERHEAT IF USED FOR HEAVY MOWING FOR MORE THEN 1/2 HOUR IN HIGH AMBIENT TEMPERATURES.
It is better to drill and tap and conventional temp gauge, but if you want the next best choice, here you go...

 

[EddieWalker]

Interesting. I've never heard of anything like this.

 

[m5040]

Most people haven't. Inside tip from repair tech. Ignore it and run hot, then wonder why all your piston seals, valves etc start leaking. Blame the machine as junk.

 

[MossRoad]

I got the PT425 because I needed the higher HP to spin the larger mower. It has a hydraulic cooler and fan. Spinning the 60" hydraulic deck or the 48" hydraulic brush cutter causes a lot of heat to build up in the fluid. I've never put a thermometer on it, but have always been curious as to the actual temps. Maybe I'll do it this year.

 

[m5040]

If you have time do a on-line search for MAX HYDRAULIC OIL TEMP. Some of the stuff will scare you. Remember if you are getting 160 to 180 in the tank, what is it running through the motors before it dumps into the tank? A little good maintenance will extend your service life tremendously.

 

[PowerTracManiac]

Good idea. When first got my machine I was wondering where hydraulic fluid temp gauge was?
Just purchased one from your link and thnks for posting.
Mike

 

[TwinOaks9]

I second PowerTracManiac, just ordered one for myself, as heat seems to be a problem with my 425 w/Robbins.

 

[Ford850]

What oil/fluid is used in these? Can you use a better synthetic which usually drops the running temperature?
I just changed the fluid in one of my Grasshoppers which only takes 2.5 quarts. But it is $22 a quart so it would add up in a larger system. I know GH specs that fluid which has more additives than some other synthetics, but I read where some shops use Mobile 1 fluid as "almost as good but lower priced". I'm just curious what these P-T's use.

 

[k0ua]

How about one of these? I have one. Very useful for a lot of things.

Amazon.com: Etekcity Lasergrip 774 (Not for Human) Non-Contact Digital Laser Infrared Thermometer Temperature Gun-58℉~ 716℉ (-5℃ ~ 38℃), Standard Size, Yellow & Black: Kitchen & Dining

 

[ponytug]

These tractors use 15W40 oil for hydraulic fluid. Changing to synthetic does not help in this application. (I have done the experiment.)

My guess is that synthetic oil has a reputation for reducing running temperature by reducing metal to metal friction by better oil film integrity. I think in this application that the heat is generated by oil turbulence, wall drag, and only to a smaller amount by surface friction heating within the motor and pumps.

Regardless, there is significant heat build up in the oil, especially during mowing, which is at wide open throttle for long durations. The added engine heat from WOT reduces the oil cooling ability of the oil radiator. My do list has included an auxiliary fan for years, and I really should get on to that project. Sigh.

Stay safe,

Peter

 

[MossRoad]

How about one of these? I have one. Very useful for a lot of things.

Amazon.com: Etekcity Lasergrip 774 (Not for Human) Non-Contact Digital Laser Infrared Thermometer Temperature Gun-58℉~ 716℉ (-5?℃ ~ 38?℃), Standard Size, Yellow & Black: Kitchen & Dining

Yep. Those tend to read a little different than a calibrated contact thermometer, but they are consistent and give you a good baseline. Very handy for other things as well. We use them to check air temps coming out of vents and will temps in rooms in buildings. :thumbsup:

 

[m5040]

I used a non-contact thermometer for a few months, but you actually have to keep it with you or in a toolbox, then take it out and use it. With the magnetic one, you just have to look at it. If it is easier, it will be done more.

 

[dragoneggs]

Keep in mind the distance to the surface you are measuring is important. If like mine, you need to be pretty close to get a good reading if there is much of a temperature gradient on the surface you are measuring. This is because the area measured is a function of the distance to your target.

 

[SpringHollow]

Quite a while ago, I tapped my tank cover for a long stem thermometer. I find it very handy. That is how I usually discover my fan has died or the connector came off.

Ken

 

[James23]

So I was in a hurry mowing the lawn this weekend and decided to see how hot it would get without a break (approx 1 acre of lawn, little over an hour of mowing). The magnet temp gauge mounted to the loader control value of my pt-180 just about registered 200 degrees. It came back down to ~180 within a minute or two of shutting the PTO valve off, but I'm really not happy to see that high of temps.

Clearly that is a problem. I even have a fan blowing across the internals of the engine. Guess I will be installing the oil cooler before the warranty is up .

What hydraulic temps do you guys that have a hydraulic oil cooler get?

Is there a write-up anywhere on adding the oil cooler? Mostly what lines to tap and what sizes they are ?

 

[MossRoad]

I've never checked mine in 19 years and I'm scared to. Why? Because it's ridiculously hot and I'd probably figure I should do something about it and mess up a good thing. So, I just run my cooling fan all the time and hope for the best.

 

[MossRoad]

I also keep the cooler fins clean with compressed air, soap and water if needed.

 

[m5040]

On my 1430 the hyd oil cooling fan comes on at 100 deg F. It is rare for the temp measured at the loader control valve to exceed 150 deg. I cut the job short if it gets to 160 deg. Depending on what job it is doing, I can tell that the wheel motor oil is very hot because it gets sluggish and needs a lot of treadle for the machine to climb over objects.
You may want to consider changing your hyd oil. Does it smell different? You have a great HD small machine, but have to work within its limitations or you will have a lot of problems.
To add an oil cooler, I put it in series with the return from the loader control valve. In theory it is very simple, you just take the line off that has the returning oil to the hyd tank and put a fan forced air cooler in-between. The only real difficult part is finding which line it is.

 

[ponytug]

Not trying to be contrarian, and just to offer an alternative view; but for what it is worth, the hydraulic cooler on my 1445 is plumbed on the return to tank portion of the PTO flow. This has the advantage of higher oil flow, and thus the opportunity to remove larger amounts of heat. It does mean little or no cooling for FEL operation. For my uses, that works well for me since I rarely have the throttle up much for FEL work, so there isn't a lot of heat being generated. YMMV.

All the best,

Peter

 

[MossRoad]

My PT425 FEL/AUX PTO circuit is always pumping no matter what. So is my MAIN PTO circuit. Neither ever shut off. The MAIN PTO flows 8GPM. I think the FEL/AUX pumps something like 4 or 4.5GPM, but I can't recall exactly. I don't know where my cooler circuit is plumbed. I'll have to look some time.