Radiator in BX2230 ruptured

[kkesler]

Tractor is a BX2230 with ~900 hours. Running a 42" bush hog yesterday, it was about 90 degrees and the temp gauge was almost at the red (where it usually is everytime I use it). Couple hours into the job I get steam everywhere (tractor had not been overheating, bubbling into the overflow, I was keeping the screen wiped off, etc.). Open the hood and on the top tank of the radiator directly across from the hose fitting is a hole big enough to poke my pinkie into. WTH? What would cause this? Don't want to put hundreds of dollars into a repair for it to just happen again if there is something that would cause this besides age.

 

[JJZ 109]

Here was one person's solution to an expensive Kubota replacement:
http://www.tractorbynet.com/forums/parts-repairs/290864-how-i-replaced-my-kubota.html

 

[Grandad4]

Sorry to hear of your problem. I have the same tractor with about 800 hours and the temp gauge has never gone above 1/2 way even on the hottest days. It sounds like yours has been running pretty hot for whatever reason.

A big issue with tractors that are used for mowing is keeping the radiator core clean. The screen catches most debris but over time a lot of fine stuff accumulates in the radiator vanes and needs to be gently washed out. I use soapy water and compressed air to clean it, typically once or twice a year. If you haven't been doing that, you will be amazed at how much crud accumulates in there the first time you clean it.

If that's not the issue, other things might be the thermostat, water pump, etc. Worst case is some engine damage causing loss of coolant.

 

[kkesler]

Here was one person's solution to an expensive Kubota replacement:
http://www.tractorbynet.com/forums/parts-repairs/290864-how-i-replaced-my-kubota.html

I'm asking around at some of these shops that do custom aluminum radiators for race cars and such, looks like for the same (or less) money I can have one made that isn't plastic.

Sorry to hear of your problem. I have the same tractor with about 800 hours and the temp gauge has never gone above 1/2 way even on the hottest days. It sounds like yours has been running pretty hot for whatever reason.

A big issue with tractors that are used for mowing is keeping the radiator core clean. The screen catches most debris but over time a lot of fine stuff accumulates in the radiator vanes and needs to be gently washed out. I use soapy water and compressed air to clean it, typically once or twice a year. If you haven't been doing that, you will be amazed at how much crud accumulates in there the first time you clean it.

If that's not the issue, other things might be the thermostat, water pump, etc. Worst case is some engine damage causing loss of coolant.

I keep the radiator cleaned out as well, wasn't that long ago I cleaned it. Mine has always run at the upper end of the scale <shrugs shoulders>. The tractor wasn't overheating when the radiator busted/fractured/exploded.

 

[radioman]

I only have one theory. corrosion. I am willing to bet where you stuck your finger in the hole if it metal it is more corroded inside then outside based on the paint . From the internet that explains it th best : When a radiator fails in a short amount of time, and you know the coolant was a recently installed name brand, check for electrolysis. Ground the negative lead of a digital voltmeter to the battery negative (ground) post or side terminal, then insert the positive lead into the coolant itself (making sure the tip doesn’t touch a metal neck or core of a radiator). If you get a reading of 0.3 volts or higher, that’s excessive electrolysis — bad news. Older cast-iron engines could tolerate that, but the modern engine with all its aluminum components cannot.

 

[kkesler]

I only have one theory. corrosion. I am willing to bet where you stuck your finger in the hole if it metal it is more corroded inside then outside based on the paint . From the internet that explains it th best : When a radiator fails in a short amount of time, and you know the coolant was a recently installed name brand, check for electrolysis. Ground the negative lead of a digital voltmeter to the battery negative (ground) post or side terminal, then insert the positive lead into the coolant itself (making sure the tip doesn’t touch a metal neck or core of a radiator). If you get a reading of 0.3 volts or higher, that’s excessive electrolysis — bad news. Older cast-iron engines could tolerate that, but the modern engine with all its aluminum components cannot.

Isn't the radiator on these plastic?

 

[JJZ 109]

Isn't the radiator on these plastic?

I'm not saying all by any means, but yes the tanks are very often plastic on these radiators. I don't know about your specific application.

 

[radioman]

Isn't the radiator on these plastic?

That was my thinking also until I realized it was a bx2200. I have not seen the BX2200 radiator in person and the op has not posted a pic, so that why i said it was only a theory. Its worth looking into.

 

[dodge man]

BX's are known for running near the red on the gauge, that has been discussed quite a bit on the forum. To the op, I'd say its just age, nothing you did wrong.

 

[kkesler]

Ok, got it apart. Weird thing is where the hole is the plastic is literally paper thin. The rest of the top tank feels solid but the area where it came apart is really soft.

 

[Grandad4]

Quite a hole! What is that "Z" shaped bead going from the hole to the core? Maybe it's from the failure of the plastic, but it almost looks like the result of some kind of repair or something. Can't really tell from the photo.

 

[kkesler]

Don't know. It peels off, whatever it is and there isn't a crack underneath it. Maybe some sort of adhesive they spilled on it?

 

[94BULLITT]

I would screw a mechanical gauge in the engine to be sure it is not over heating or use a IR thermometer to see how hot the top radiator hose is.

Flush the block out really good before you put it back together. Don't forget to used distilled water with the coolant.

 

[radioman]

ouch ! from the pic -- the hole looks like its been worn through from the inside. Its kinda like it was captivating or something .I never heard of this happening so I'd replace the whole rad. It would take you a step away from other problems the rad would have.

 

[BeezFun]

Could some kind of solvent have gotten on it, and over time degraded the plastic and made it soft? Have you ever used any kind of degreaser on the engine, or wiped it off with a solvent like acetone?

 

[kkesler]

No, never used anything but water under the hood. I spray it off with the hose before I service it, that's it (I'm not exactly what you call a clean freak ;D). The coolant looked fine, nice and green and I check it annually with the tester to be sure the antifreeze temp is still good. The radiator does look like it was worn from the inside but I don't see how, the coolant feels slightly slippery between the fingers like it should, no hint of anything abrasive in it. Maybe it was a manufacturing defect and the plastic was just thin right there. Who knows?

 

[Gator6x4]

Some anti freeze has a corrosive effect on plastic. Ask GM about that one. Anti-Freeze destroyed many of the plastic intakes on GM products. GM experienced plastic melting with Dex-cool anti freeze. Dex-Cool used to use 2-EHA and any other anti-freeze that still uses 2-EHA will cause melting problems with plastic.

Antifreeze

Organic Acid Technology or OAT's are coolants that are formulated without the use of silicates. Since silicates have a short life, removing them allows a longer service life. Typically, coolants advertised as 5 year, long life , extended life or Dex-cool are examples of OAT's. Common components to OAT coolants are Carboxylate, sebacate, and 2-ethylhexanoic acid (2-EHA), which are corrosion inhibitors, used instead of silicates. Depending on which manufacturer is filling the jug, the inhibitors may change. Dex-cool uses 2-EHA which among other things is a plasticizer which has the effect of softening plastic. GM intake manifolds are made of plastic........... If it is found that Dex-cool is dissolving the gasket material, it will validate what some folks have been saying for a long time: Dex-cool eats gaskets. We'll see. Prestone doesn't use 2-EHA in it's long life coolant, instead uses carboxylate.

 

[kkesler]

Some anti freeze has a corrosive effect on plastic. Ask GM about that one. Anti-Freeze destroyed many of the plastic intakes on GM products. GM experienced plastic melting with Dex-cool anti freeze. D

Well ain't that a heck of a note. That truck in my avatar had to have two intake gaskets before I switched it over to green, no problems since.

 

[ruffdog]

Is the melted hole area right where the hot coolant from the engine comes in the radiator and hits first? That goo you peal off near the hole might be melted plastic.??

 

[Recoveryhill]

BX's are known for running near the red on the gauge, that has been discussed quite a bit on the forum. To the op, I'd say its just age, nothing you did wrong.

If thats the case, glad I don't have a BX. My feelings however are that there must be a contributing factor. If I purchased a new BX and saw temp "running near the red on the gauge", it's trip back to the dealer would be a blur. If I had one with only 900 hours and saw the same thing, I'd be a blur headed to the shop to find out why. Small displacement Kubota diesels power reefers and generators and run well into tens of thousands of hours with proper maintenance, doing work.

My L model, 37HP, barely gets off the bottom of the temp reading, ever. At 900 hours, has the coolant been replaced, system flushed and how may years did it take to get to 900? Every 12 months I drain coolant, flush system and replace with proper pre-mix coolant. If you do this and keep the radiator and screen clean and have the proper level of coolant you have another mechanical problem.

There is no excuse for your tractor operating near the red line, as a normal condition. There's ample bitching about items like 3pt hitch jerks but small block Kubota diesel engines are among the world's most dependable.

Send a sample of your oil to Blackstone Labs and pay attention to wear indications in your results, go ahead and buy a new radiator, flush engine and replace coolant in the proper ratio with water and accept nothing less than proper coolant temperature.

Conclusion:

Clogged screen/radiator
Low coolant levels not monitored or corrected - evaporation is a *****
900 hours in ? years - stale coolant and or internal corrosion in radiator
Water Pump
Head Gasket
Clogged screen/radiator

Best of luck but well engineered diesel engines don't "just overheat" for no good reason. Trust me, there was a reason for your failure and when corrected you will no longer be operating at the red line.