Hi folks, I have a Terex PT110 Forestry that's sometimes getting high hydraulic fluid temps. Does anyone know what the fan RPM is supposed to be? I'm wondering if maybe the fan isn't doing what it's supposed to be doing. Does it change with hydraulic / engine temps? Thanks.
Have you cleaned the oil cooler and radiator lately ? The complete maintenance manual is here → http://constructionsupport.terex.co...rex Tier IV/US Terex PT-110 O&M (2-25-13).pdf
Thank you! Yes the cooler is clean. New fluid and filters too. The manual only goes into the reverse interval. I'm wondering what RPM the fan is supposed to be spinning. It seems to be kind of slow. Like maybe 300 rpm. I might have an indication / sensor problem also. High hydraulic fluid temps can cause derate, thats the PITA part with this problem.
How is the powered ? Belt or electric ? Are the blades clean and undamaged ?
It's hydraulic and variable between about 250 and 2500 rpm. The core of the question is more about what controls the fan motor. Is it engine RPM, is it fluid temp? Is there a solenoid valve somewhere that's not working? Is the heat exchanger working? What fluid temps should I be seeing coming out of the heat exchanger? I don't know, and the shop manual doesn't mention, as far as I can see. The O/M doesn't either, of course. Unfortunately, this isn't a "horse sense" issue. It's going to take someone who actually knows this machine. My shop book doesn't even have hydraulic schematics in it. It just has a troubleshooting section that mentions stuff like "clean the heat exchanger" and "make sure hydraulic fluid is topped off" and "don't run until you figure this out" and some other worthless bits of crap. Every time I run into a Terex, I run into stuff like this. I'm a fairly decent mechanic, but without reasonably good documentation, I'm just going to be throwing parts at it until it works. Sorry I blabbed a bit there. I'm frustrated because I'm not a dealer, just a loner independent. Thank you for trying!
Trace the hydraulic hoses from the fan motor to wherever /whatever is supplying the oil to it. It might have a valve controlled by oil temperature very close to the hydraulic pump, IMHO. Don't discount the possibility of a failing fan motor.
Many times the parts books are your best source of the parts arraignments ! Hopefully there is info in the service manual for #18 ---Manifold Fan Control. It appears to have an adjustment on it. Go here for further details of the fan circuit. https://www.trackloaderparts.com/terex-pt110-forestry-09-a-radiator-and-oil-cooler-assembly/ Click on the image I posted to enlarge it.
Like car owner manuals these days. No real help just ..."See the dealer" every page. A waste of paper!
I just took another look at the piping and noticed #15 goes to a charge filter. You may want to change it.
And here is the manifold drawing clearly showing the electrical connection above #7 that most likely goes to a sensor.
And here is where the temperature sensor (#32) is located. I have no idea how you check it for a malfunction. Maybe the service manual has something in it along with the electrical schematic.