Here is the situation I am running into. 2010 D6T, 8,700 hours. I am pushing sand and lots of it. all fluid levels ok. I bought the machine used and it came out from a fly ash operation. I have cleaned/lightly power washed the radiator multiple times and have removed a lot of fly ash chunks that were in between the radiator fins. the machine runs great for about two hours. Temp levels stay consistent. Then, after about 2.5 hours the machine temps get to the large tick on the gauges and then goes above them. If I’m pushing and running the machine they just keep going up. Temps are never in the red, but they also can’t bring themselves down unless I idle the machine for 15 minutes. I can run for about 20 minutes and up they go again. could this be due to more blockages from the ash or something else? thanks
Post your serial number of the machine. Have you checked anything yet other than what you have done with washing out the core?
KJL01125 I have not checked anything other than what I mentioned. I forgot to mention that both temps start to get hot, both engine and transmission.
When you say “idle the machine for 15 minutes” that is at low idle speed, correct.? Have you ever tried running the engine in neutral at about 1500rpm or so.? How fast do the temperatures come down then.? Also have you had the belly guards down and cleaned underneath the engine and transmission.? If that machine was operated in fly ash it probably is long overdue a clean downstairs.
The more I think about it the more I suspect that your problem could most likely be a lack of air flow through the cooling package, because not only do you have the radiator cores in there but also air-to-air coolers for the powertrain oil and the hydraulic system as well. If you have A/C the condenser is probably shoehorned in there somehwere as well. I can't help but think that at some point the hardnose will have to come off and the whole cooling package will need to be disassembled to clean it, but let's try every possible avenue short of doing that first.
I was referencing low idle when I said idle. I tried the 1500 rpm in neutral and it didn’t seem to help much. Do I have to remove the belly pan to clean in there or do I stick a power washer in there to try and clean it?
That seems to suggest a possible air flow (as in lack of) issue. Do you have access to an infra-red (non contact) thermometer.? I would remove them if it was mine because your tractor has sealed bottom guards. What you can do pressure washing down the side of the engine will be extremely limited. There are a total of 3 pieces that need to come down, from the front right the way back to the one under the rear gear case at the back end of the machine, and they will be heavy with accumulated dirt so you need to be VERY careful with them. The front two are pivoted on one side and can be tilted down using a lever puller hoist from above so they won't have to come right off to get them clean.
I looked into the belly pans through the space up front and they look clear and clean. I also took a video of a belt from the fan that goes over to some type of mechanism next to the oil filler tube. It seems as though the belt is slipping on this item. Would that be contributing to this issue at all? again, I apologize for my lack of knowledge, this is my first dozer.
Can you take some photos of the inside of the belly pan so we can all see.? Also please post a photo of the belt that you are referring to.
I can try and get photos of the pan tomorrow. I’ll try to attach a photo of the belt I’m referring to.
That’s the aircon compressor belt. It doesn’t drive the radiator fan. I think the main radiator fan is hydraulic drive, let me check.
The hydraulic temp never gets too hot. on the radiator itself, I see three different types. is the one in the engine compartment on the right side looking out the hydraulic radiator? That’s pretty clean. then if I look in the front grills, there’s one type of radiator on the left, is that the transmission? It’s maybe 12” wide or so. then in the middle and to the right of the front, is that the engine radiator? I thought I came across a cooling system picture on here, but it wasn’t exact to my machine.
It’s difficult to find a single drawing that shows all the elements of the cooling package unless it’s for training purposes and I don’t have that. Again if you post a photo I can annotate it for you. As I asked above do you have an infra-Red thermometer.?
Might check the temperature drop across the powertrain cooler, if it’s heat soaking the cooling system, it will have a hard time keeping up. If that turns out to be the case you will need to run the machine until the overheating begins and check torque converter inlet/outlet pressures along with transmission lube pressure. Certainly sounds like your powertrain is generating heat faster than your cooling system can get rid of it. Remember, the transmission temp on the dash is referring to the torque converter outlet temp. This is the temp of the oil entering the cooler.
Also, looking at the front of the tractor through the grille, the far left core is your aftercooler, all the ones to the right of it are radiator cores. On the inside by the fan guard is your hydraulic cooler, the powertrain cooler is mounted under the turbocharger on the right side of the engine block.
I know we had all sorts of issues with our D6Ts keeping the radiators clean. What can look clean from the front of the tractor looking through the grille or from the engine compartment looking forward was not the whole story. The areas behind the baffle indicated by the 4 arrows were favourite spots to get full of material that severely restricted airflow through the radiator.
I don’t have a thermal temp gauge. It I can get one. should I take the temps in different places? Any temp I’m looking for?
Would it be ok if I ran the dozer until it got hot, then idle it down to cool, and hop in the excavator to use that for a couple hours. Then hop back in the dozer for an hour or two? that’s until I can get it fixed. We’re under a time crunch and can’t get the dozer in the shop at the moment. what damage am I possibly doing if I take it up to hotter temp but don’t run it there?
Take the temps of the hoses connected to those two big tubes shown coming out of the bottom of the radiator in the illustration above. The one on the left side of the tractor is the inlet, the one on the right is the outlet..
This Tractor looks like it could do with a Good Service and all the panels and grill plates stripping then steaming out, your fuel filter looks to be full of puss, if you cannot see light through the cooler fins then wind off the fan is not removing any heat, the dirt pegging is near always greatest on the lower right hand side looking in through the side doors, a temp gun is handy but if the rad is pegged a bit of rag used as a flag waved about with the fan running at 3/4 speed will tell you a lot on air movement, the low idle cooling better than at half speed is not the common thing so this needs checking for more detail, if you have a heat gun the top to bottom of the radiators can be checked all points of a compass with often an 8 -10 deg change, washing out with a steam cleaner often gets the best results but guards etc need to be stripped off first, to pull off the nose group you will need metric bolts to draw the nose pins. tctractors
I’ve had a little experience with fly ash. It sets hard in fins.It also acts as insulation to the sump. My thoughts are a major clean up operation is needed. All belly plates off and possibly nose cone as you simply won’t clean anything more that 50% of the radiator(and that’s the bits that don’t block up).
There speaks the voice of experience..............
I bought an IR temp gun, what temps should I be looking for off those hoses into and out of the radiator?
Look for the difference between the two temperatures, not the temperatures themselves. This will give an indication of how well the radiator is cooling.
The left inlet hose was around 135° and the outlet on the right was about 122°-125°. Both temps bounced a couple degrees but it is close.
Was that with the engine running at low idle.?
Yes at low idle. Both the trans oil and engine oil were at the higher/thick tick mark, running hot, but not in the red. I ran the dozer until that point, idled down and checked the temps.
In that case I would say that the radiator cooling performance is borderline at best. That style of radiator there should be an 18-20 Deg temperature drop between inlet and outlet, not the 10-12 Deg that you measured. These temperature readings point to the outside of the radiator being nowhere near as clean as you think it is. As Nicky68a pointed out above fly ash has a habit of bonding itself to metal surfaces. This may have happened in your case. Have you closely inspected the fan blades for wear on the tips.? Can you post some photos.? That may provide another clue. EDIT: Hang on a minute. You are talking 135 DegF inlet and 122-125 DegF outlet, right.? That is waaaaay off what "Hot" should be on the gauge. I would imagine an inlet temp to the radiator somewhere around 190 DegF would be classed as hot. Something does not add up here.
Follow the lines from the radiator inlet (right side) back to the engine and you will find the thermostat (water temperature regulator) housing. Take the temp of that point and of the radiator inlet and compare the temperatures of those two points. If you can run the engine coolant temp just up to the red on the gauge that would be good.
I see 230° on that housing.
That's more like it. So why I wonder would you only see 135 on the radiator inlet.? I know you said before that you are on a tight schedule work-wise but do you have time to replace the water temperature regulator aka thermostat.?
Is 230° ok? Does that point to that thermostat is faulty? I have a week and a half to run it and then I have time to make repairs.
The inlet I am taking temp of the hose. Should I take the temp of the radiator itself?
I see 190° on the lower portion of the pipe that is leading to the water housing.
230 on the housing compared to 135 on the inlet hose (that's a good enough place to measure it) like you originally said would put the temp regulator under suspicion. Even 230 vs 190 is suspicious. 230 at the housing vs something like 220 at the radiator inlet would be somewhat more "normal". If you don't have time to get into the cooling system until you finish the current job then best continue as you have been switching between the dozer and the excavator. That's all I can suggest. When you do finally get into it you may be up for changing (or at least disassemblnig) far more than just a thermostat.