BX2360 overheating......still

[SDMauler]

Hey everyone. I have a 2009 BX2360 with a 60 inch MMM that is overheating when mowing- I posted earlier about this. The deck is fine, the blades are sharp, it's well greased and all of the bearings are good, including the idler/tensioner, so I don't think it's caused by the mower per se, but by the load it puts on the motor. It doesn't overheat if you sit in the driveway with the mower running, but as soon as you load it by cutting grass, it starts its climb to the top, within 1/8 inch from the red zone. It's never actually boiled over, but this can't be good for the MTBF of the engine. I've taken the radiator out and washed about 47 pounds of dirt and oil from a hydro leak out of the fins, and you can see right rough the entire radiator now. I checked the inside tubes, and they look good at the top. I also changed out the thermostat, which had no effect at all.

I used an IR thermometer to check the temp right at the sensor, and it showed 238 degrees F. I tried to get some readings on the top and bottom of the radiator, and came up with around a 40-50 degree temperature drop from bottom to top, which isn't bad considering it was 90 degrees at the time. I have a bit of mowing to do, so I will rerun the temp readings today. If you let it idle down for 10-15 minutes, it cools down to about mid-range on the gauge.

I noticed when I drained the radiator last time, there were several ( maybe 50) very small shiny metal particles in the bottom of the coolant pan. The only thing I can think this is from is the water pump (guess it could be from the factory, but I've changed the coolant a couple times since new).

Power seems fine, and the hydraulics are all working properly. Fuel consumption hasn't really changed any either. There's no water in the oil or vice-versa, no leaks anywhere, and the fuel system Works fine. I would think if it were fuel starved, the power would drop off considerably. The air filter is near new. I always run it pretty much WFO when mowing, minus a couple hundred RPM.

Should I just bite the bullet and pull the water pump for inspection? Has anyone had a similar issue they have fixed?

Thanks for sharing from the knowledge base out there.

 

[JackJ]

Sorry, no keen insights into what the cause of your overheating might be, but the shiny particles in your coolant sure sound like a symptom that might indicate your problem. Whether or not they're from the water pump, I wonder if particles might be creating a partial blockage somewhere.

With your mower affecting your engine temps so significantly, I'm also wondering if you've used your IR thermometer to see how the transmission temp is affected? No dash temp gauge or warning light there to raise concern, but while my engine hasn't shown signs of getting too hot, I've seen some pretty high readings pointing the temp gun at the back of my tractor after mowing. I'm trying to get a grasp of how a load at the PTO compares to the load when driving hills, and when giving the FEL a real workout.

 

[tinkerwitheverything]

First have you owned it from new .You mentioned that you changed the Anti Freeze a couple times since new. If you've owned it from new did this problem just started ? Metal shiny pieces sure doesn't sound good.I think your on the right track of a possible water pump problem. Now if it was me I'd be taking the water pump off just to make sure that its no flying apart ???

 

[North Idaho Wolfman]

Is there any smoke?

Pull the radiator cap run it get it warm and look for bubbles.
If you have bubbles, your looking at a blown head gasket.
If no bubbles look at circulation, if it looks low or week, I would pull the water pump.

 

[SDMauler]

Good points, all. The hydro system isn't that hot, around 170. I just took some more temp readings, and the differential between the top of the radiator and the bottom, as measured by removing the knee-banger panel and shooting the radiator next to the battery box is more like 15 degrees., and around 160 for the high.

I bought this tractor new. The first couple of years, no problems, but over the last 4 or so years, it's getting progressively worse. I only notice it in the summer, obviously.

Wolfman, no smoke at all. And no bubbles, but no good circulation either. When the temp gauge got to 90% full deflection, the water at the top of the radiator was only 136 degrees, just barely warm, and I didn't see a lot of coolant rushing by the cap neck, it just sort of shook around in there. The level did change a little when going from idle to full throttle, or vice-versa, but not enough to make it spill over. I'm definitely thinking either a vane broke off the pump and ground the rest down (that would also explain the tiny metal particles in the coolant) or its plugging a cooling passage somewhere. Sounds like a good reason for the wife to buy me a bore scope and a new water pump?

Thanks all. I'll let you know what I find. It will be next week, since I will be headed for the lake cabin this weekend.

 

[67Truckin]

Have you also checked the fan belt to make sure its tight enough to not slip when turning the fan and waterpump pulley? Is your dash temp gauge working properly? Has the coolant temp sensor gone bad?

 

[Valley Viking]

Have you cleaned the radiator screen? The screen quickly gets plugged up with grass clippings. I clean the screen on my BX regularly. I have a G1900S that has the same motor configuration as the BX's do. The G1900S has gotten hot on me a couple of times when I neglected the screen.

 

[SDMauler]

I clean the screen several times a day, and flush the radiator fins with a water wand at least once a week. Nothing changes after I do either. I double checked the gauge reading with my IR thermometer, taking a reading on the sensor itself, which was around 238 degrees. I'm going to pull the water pump when I get home. Anyone have a picture of a new pump? Messicks doesn't have one. Or, maybe I'll go ahead and order one with a new gasket, and compare them.

 

[plumbcut]

I clean the screen several times a day, and flush the radiator fins with a water wand at least once a week. Nothing changes after I do either. I double checked the gauge reading with my IR thermometer, taking a reading on the sensor itself, which was around 238 degrees. I'm going to pull the water pump when I get home. Anyone have a picture of a new pump? Messicks doesn't have one. Or, maybe I'll go ahead and order one with a new gasket, and compare them.

Im guessing water pump too. Maybe the impeller is slipping on the shaft.

You could remove the t-stat and see if that makes any difference. And while you're there, after removing the t-stat, remove the top radiator hose from the radiator and run the engine and see how much coolant is actually being moved. You could do this by just keeping the radiator full with the garden hose. Harder to do with the t-stat installed because the cold water keeps it shut...

 

[85Hokie]

I clean the screen several times a day, and flush the radiator fins with a water wand at least once a week. Nothing changes after I do either. I double checked the gauge reading with my IR thermometer, taking a reading on the sensor itself, which was around 238 degrees. I'm going to pull the water pump when I get home. Anyone have a picture of a new pump? Messicks doesn't have one. Or, maybe I'll go ahead and order one with a new gasket, and compare them.

238 is high .......

first check the thermostat as mentioned - you can throw it in boiling water just as a double check as you run it without.......the IR will allow you to track down the problem too!


http://www.messicks.com/part/1g470-73034/assy-pump-water

http://www.ebay.com/itm/Water-Pump-...50D-BX2360-hub-gasket-Free-Ship-/171797827654

http://www.kumarbrosusa.com/kubota/water-pump-d902.html

 

[MadMax31]

From working on boilers for many years, Im guessing your water pump impeller is worn out. Sounds like the mmm is the toughest load and the diminished flow is causing the higher temps. Ive seen solder bits and sand get into impellers and just sand blast em tell their useless.

 

[85Hokie]

"Sounds like the mmm is the toughest load"

My B7100 runs 30 degrees hotter when the MMM is in use @ 90% WOT
Tractor stays at 210F cutting grass, 180 when not.

 

[67Truckin]

My BX1800 with a 60" MMM runs about 1/4 gauge mowing grass. Sounds like you may need to take a look at that waterpump.

 

[Pap]

If you are getting no flow replace the thermostat first! If it won't open the coolant can't flow. If no flow after that then move on to the WP.

 

[Tooljunkie]

Easiest flow test is to pull thermostat and run it.
It needs a proper operating thermostat to regulate engine temp. Not only to keep it at operating temp, but by cycling it slows coolant flow in rad allowing it time to scrub off some heat.
Depending on rad design and inlet /outlets, flow may not appear as if much coolant is flowing.

I just purchased a cooling system test kit,made by uview. It is a test to determine if combustion gases are entering cooling system. I do not believe this is the case,as even the smallest leak will cause issues at higher rpms if not under load.

Maybe drop a few coins on a new temp sender, could be as simple as that.

 

[Bulldog]

My L3000 would get right at the red while mowing when it was new. After I switched it to Amsoil I've never had another problem.

 

[SDMauler]

All: thanks for all the valuable input. I will pull the t-stat and boil test it. I'm sure it will be fine, as it acted the same on the old t-stat. Then I'm going to pull the water pump. I'll let you know what I find.