I have a komatsu pc40 great machine in the mini ex. range just one problem they over heat in the summer on 85 degree days. They just dont move enough air. My machine has around 4000 hrs on it but I have two friends with the same make and size one of them just a year old and another with a new deere 50 same problem. Im thinking of putting an electric fan with a thermostat control on mine any ideas out thier or with the same problem. ATCO give me your thoughts you seem sharp with a lot of experiance thanks guys.:
Well, thankfully, we're going into the time of year that you have the rest of the winter to figure something out. It's interesting that you note of other machines that you know of that have the same problem. I haven't worked on many of the mini-ex units. I kinda like your idea of installing and electric fan. Have you got room to fit one?
electric fan may help maybe an aftermarket bigger radiator, if available... water pump could be shot ... blades worn, not moving enough coolant.. thermostat stuck open, coolant moving to fast thru the radiator to cool it. Have you tried steam cleaning the radiators and cooling coils. Make sure the fan belt is tight if thats what drives the fan. fan shrouds in place... radiator cap is good...good coolant mix ....does it have a water filter...
The biggest problems with these that I have seen is that debris gets between the hydraulic oil cooler and the radiator blocking the air. Many times there is a plate under the space between the radiator and cooler that you have to remove to let the debris fall out. You might check that before going to any more expensive repairs or retrofits. I never used a pressure washer or steam cleaner to wash out the fins on the coolers. Instead I drilled a one sixteenth hole in a pipe plug, put the plug in a length of half inch pipe and put a ball valve on the other end. I hook that up to my compressor and blow the radiator and cooler out at least once a week. Good Luck!
check all the basics, does your fan have a thermostatic hub? (a failed hub will not allow fan to move at full speed) does your fan suck through the rad or blow through the rad?? (a blow fan will cool better) Is your fan the proper depth in the shroud? Is your A/C running during overheating?? (ac loads engine more + produces more heat)
There may very well be something wrong with his machine causing his problem, but the thing that interests me is that he said he had two other friends with the same make and model having the same problem as well as another friend with a new Deere 50 having the problem as well. I don't have a great deal of experience with mini/midi ex machines, but what I do know is there ain't a whole lot of room in there for nothing. Everything is crammed in so tight they're a PITA to work on. I seem to recall seeing other threads in the past reporting this problem on these size machines. And I for sure recall seeing threads of these machines that don't have A/C that works worth a flip when the temp gets above the 85 / 90 range. I'm curious if it's just a common problem with these small ex's. Very tight space to put an engine with all the goodies and still have enough room to have a radiator and air flow large enough to cool engine efficiently. I don't have a clue...but find it curious.
They brought a hotsy out the jobsite once after hose blew on a hydraulic fan motor , and push all the hydraulic oil thru the radiators and such.... while it was there... they cleaned about half a dozen other pieces while there... not for show.. engine area and radiators
Wolfman, I also have a pc-40r8 and had cooling issues last summer. a 90 deg day and I was almost afraid to run it, it would run so hot. I ended up pulling the antifreeze radiator out and it was totally plugged with debris. tried to clean it with out removing it from the machine, but there just isn't enough room to get in there.. I figured it was time to change out the antifreeze anyways. It ran a lot cooler this summer. Jim
Make sure all the foam insulation is around the radiator. If there are any gaps it will not cool properly either.
Look inside the radiator neck also most all excavators use a radiator with very small tubes in them and they will plug up. Also if you have to replace the radiator make sure you install the same type with the same number of cores we have had to replace several at our dealership where somone just went and got a radiator the recored and the tubes were not the same and then they could not figure out why it still overheated
We have never had a problem with our Hitachi/John Deeres, but we have a Cat mini that will do the same overheating. I have to remove the hyd cooler, clean the radiator-I use a water hose, wash it out, wash out the hyd cooler fins and bolt the cooler back up. Cat was gracious enough to have enough slack in the hyd lines to allow me to unbolt it and swing out of the way without unhooking the lines. The amount of dirt and dust in the radiator is amazing. Once I wash it out it will run fine for another month or two, before I have to do it again. I realize that this is just a routine maintenance issue, but I have never cleaned out the Hitachi/Deeres , they never run hot and don't appear to accumulate dirt and dust the way the Cat does.
Well, there's another with a clogged radiator. Amazing. wolfman...have you checked yours yet?
:usaWolfman....hmmmm many good ideas...i have one that will take just a few mins. to do and it has bn a issue for Komatsu for awhile..install pressure gauge on top of control valve and check unload presuure at neutral...your PC valve could have blown o rings since you have 4000 hrs. on your unit...if unload is more than 22kg's then you have leakage and overheating will result:usa.
+1, We had a PC 40-6 that would overheat. Replaced foam with sheetmetal and a rubber gasket around the outside edge where it touches the hood and problem was solved. Machine was actually a Bobcat 116, which was a repainted PC-40.
I have a Volvo EC 45 and one day this past Summer it also ran hot but it was about 100 degrees. One thing that seemed to cause me problems was I was loading a dump trailer which took about 4 minutes then letting it idle while I drumped the trailer (which took about 2 or 3 minutes). It seemed letting it idle cause it to run hot as I soon learned to let it run about 1500 rpms while dumping the loaded trailer and it did not not run hot. This machine has no ac. Only God's breeze and now my fan. I normally don't run at full rpms but about 200 lower. On a tractor found out clogged air filter will also cause engine to run hot and on same tractor found out just a layer dust in radiator vents did also. Did find a leaf blower was good to clean both.
hydraulics will make an engine generate heat, maybe a louvered door or pump access, will help.
Or could you open the hood to the engine to let more air in/out, or luvers with a fan if cleaning didn't work
I just bought a couple of 24vdc 850cfm blowers from this place for $15 each. https://www.surpluscenter.com/electric.asp?UID=2009103014460485&catname=electric Don't see them listed currently, but something may turn up that will fit your needs. I was having minor overheating problems with my Kobelco, but I think destroying the rad with some metallic debris will eventually solve the problem. Pulling the damaged rad uncovered a pile of garbage wedged between the rad and hydraulic cooler. We had used a pressure washer on the radiator previously and thought we had a clean system, but all the trash buildup between the two was restricting the airflow.
Old thread but I'll weigh in. My PC40-7 seems fine, I keep it reasonably clean. I ran it hard all day in early September for a couple of days and no problems at all. It has about 3300 hrs. It does have a weak swing motor however and if anybody has any knowledge on that problem please let me know.
Is the slew low on power or speed?
Plenty fast, just a little weak.
Old thread but FWIW our TB070 can't run in the summer w/o the hood wide open. Screen's clean, rad is flushed, coolent checks out, just runs hot and the hood gets opened as soon as I go thru the warm-up routine May-Oct. Just a livable quirk.