Hello all, I have a BX2200 I bought from my father 3 years ago. I have done oil changes yearly and changed the hydraulic oil once with super UDT. My problem is I now have oil in the radiator. I quickly popped the drain plug and have no water in the oil. I have no loss of power and it does not overheat. Can anyone diagnose what the problem may be?
Oil in radiator
- Thread starter 1st BX
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Don't live in the "wishful thinking" world, just because there's no water in the oil. That is not always a foolproof diagnostic. (And you won't really know for sure unless you have the oil tested, anyway.)
There is one possibility I can think of that isn't really bad: You have an oil cooler in the radiator, and it's leaking. IF that's the case (I don't know on your tractor), it needs to be addressed quickly before the contamination goes the other way and you trash some bearings. Antifreeze and babbit metal do not get along well!
If it's not that, it's worse. You have one of these:
You need to find out which it is, and the sooner the better.
There is one possibility I can think of that isn't really bad: You have an oil cooler in the radiator, and it's leaking. IF that's the case (I don't know on your tractor), it needs to be addressed quickly before the contamination goes the other way and you trash some bearings. Antifreeze and babbit metal do not get along well!
If it's not that, it's worse. You have one of these:
- Bad head gasket.
- Cracked head.
- Cracked block.
You need to find out which it is, and the sooner the better.
Might not hurt to run a test.
RCW
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BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
38 hours.... to do WHAT? Is he assuming it's a cracked head or block? Why is he assuming anything?
Somebody recently said they were quoted 60 hours to replace an engine.
Yeah, it seems excessive to me, but then, I"ve never pulled a tractor engine. But I can pull an older car (back before the engine compartments were like sardines) in a whole lot less than that! More like a day, and I"m no pro at it.
Before I paid out that money I'd want to invest in a few tools and do some testing. You need to pressure test the system, do a compression test, and a leak down test. You can learn a lot that way.
RCW
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BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
A decent redneck test. It’s not definitive of much, but take radiator cap off and start the engine.
If you see a lot of bubbles in the radiator, it can be an indication of a head or head gasket problem.
If you see a lot of bubbles in the radiator, it can be an indication of a head or head gasket problem.
whitetiger
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Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
There has never been an oil cooler in any BX series tractor radiator.
You most likely have a leaking head gasket.
You most likely have a leaking head gasket.
Anyone have a shop manual for head / head gasket replacement. I am a little better than average mechanically, so If I can figure what I need and have it on hand before I start I believe I should be able to do the work. looks like I can get a replacement head and gasket kit for between 6 an 7 bills.
Disclaimer: All my context is from working with 6BT Cummins motors. And, early Chrysler flatheads.
Without knowing anything about the engines in the B-series Kubotas, it sound like you're dealing with a head gasket issue. But, I would highly recommend getting the head magnafluxed, once you have it off and stripped. That will rule out a crack in the head. So, budget some time in your repair schedule for that.
Cummins engines are notorious for cracks between the exhaust and intake valve seats. You might be able to spot such a crack with the naked eye. May be repairable.
I used to drive a 1937 Plymouth P4 coupe with the flathead 6. I hopped up that engine by installing aluminum pistons and shaving a BUNCH off the head to increase the compression ratio from its original 6-something to one. The trick to getting the head gasket to stay sealed was to spray it with cheap spray paint, and install it while the paint was still tacky.
If you have the budget, plan for new head bolts. That will improve your chances of an effective head gasket seal.
Just some crazy Ol' School sh_t...
-Paul
PS, if you determine that the head gasket failed, DEFINITELY get the head planed to make it flat again. That's a non-negotiable.
Without knowing anything about the engines in the B-series Kubotas, it sound like you're dealing with a head gasket issue. But, I would highly recommend getting the head magnafluxed, once you have it off and stripped. That will rule out a crack in the head. So, budget some time in your repair schedule for that.
Cummins engines are notorious for cracks between the exhaust and intake valve seats. You might be able to spot such a crack with the naked eye. May be repairable.
I used to drive a 1937 Plymouth P4 coupe with the flathead 6. I hopped up that engine by installing aluminum pistons and shaving a BUNCH off the head to increase the compression ratio from its original 6-something to one. The trick to getting the head gasket to stay sealed was to spray it with cheap spray paint, and install it while the paint was still tacky.
If you have the budget, plan for new head bolts. That will improve your chances of an effective head gasket seal.
Just some crazy Ol' School sh_t...
-Paul
PS, if you determine that the head gasket failed, DEFINITELY get the head planed to make it flat again. That's a non-negotiable.
Last edited:
RCW
Well-known member
Lifetime Member
Equipment
BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
cummins is not kubota and kubota is not cummins
they share nothing in common, except on the M8 series tractor which uses a cummins engine but the M8 is pretty good sized compared to the BX
BX is kubota built engine. It doesn't have an oil cooler at all.
take the radiator cap off and top off the coolant. Water is fine if it's just a little low. Make SURE the engine is cold! Now go start the engine and idle it up to about, oh, 2200 should do it. Now look into the radiator with the cap off. Bubbles mean leaking head gasket or possibly cracked head. Or both. Seen that a bunch of times.
I can change all 3 connecting rods in a BX in about 5 hours, give or take....that's removing the engine, setting it on a bench, disassembly and reassembly. 30 hours?? Find another dealer. But I ASSUME they are esimating and dealers almost all estimate high. I can normally do a cylinder head R&R in about 2 1/2 hours, give or take. Pretty easy on a bx. Had a dealer quote a cyl head R&R on a ZD326 a while back, the owner is a friend and asked me for council. They quoted him 5.5 hours to remove it and inspect. I told him I can have it off in about 30 minutes. Then of course it shows up at the house....like I have time to work on yet another project. But we eventually got it done without issue and it's been great ever since.
oftentimes a leaking cyl head gasket will allow oil to slowly get into the coolant. It's cumulative and people don't often check the coolant so it builds and builds with run time and that once every two year coolant check, you find evidence of oil/fuel/exhaust gases in the coolant and then OMG what happened? "I just checked it". And by the way yes I'm guilty.
they share nothing in common, except on the M8 series tractor which uses a cummins engine but the M8 is pretty good sized compared to the BX
BX is kubota built engine. It doesn't have an oil cooler at all.
take the radiator cap off and top off the coolant. Water is fine if it's just a little low. Make SURE the engine is cold! Now go start the engine and idle it up to about, oh, 2200 should do it. Now look into the radiator with the cap off. Bubbles mean leaking head gasket or possibly cracked head. Or both. Seen that a bunch of times.
I can change all 3 connecting rods in a BX in about 5 hours, give or take....that's removing the engine, setting it on a bench, disassembly and reassembly. 30 hours?? Find another dealer. But I ASSUME they are esimating and dealers almost all estimate high. I can normally do a cylinder head R&R in about 2 1/2 hours, give or take. Pretty easy on a bx. Had a dealer quote a cyl head R&R on a ZD326 a while back, the owner is a friend and asked me for council. They quoted him 5.5 hours to remove it and inspect. I told him I can have it off in about 30 minutes. Then of course it shows up at the house....like I have time to work on yet another project. But we eventually got it done without issue and it's been great ever since.
oftentimes a leaking cyl head gasket will allow oil to slowly get into the coolant. It's cumulative and people don't often check the coolant so it builds and builds with run time and that once every two year coolant check, you find evidence of oil/fuel/exhaust gases in the coolant and then OMG what happened? "I just checked it". And by the way yes I'm guilty.
...except that they're both high-compression, valve-in-head engines. The problems we're suspecting here are certainly not exclusive to one brand. All internal combustion engines are more or less susceptible to them.
Just curious, lugbolt, how often did you determine that the sealing surfaces for the head gasket were untrue? I would suggest that this is a very common reason for head gasket failure. Or, do Kubota heads not warp? How common is head gasket failure in small Kubota diesels?
lugbolt, I truly appreciate the perspective you bring to this forum. Would be great if you could bring some perspective to the causes of water-in-oil problem that are specific to the small Kubota diesels. And, how susceptible Kubota diesels are to the insults that result in those problems, relative to other brands.
Thanks,
-Paul
I appreciate everyone's help here. I was thinking it would be one of the 3 original "Bad" issues, but was hoping there was something in this engine that could cause the same same issue and not be as "bad". I really am very vigilant on checking ALL fluids before each use, so I know the oil was not in the cooling system the week prior when I tilled the garden, and am about 1/2 a quart low on oil now. the tractor sat for a week before I found the oil in the radiator, and when I pulled the drain plug I did not get any water out and the oil is not milky; so hoping there is no water in the oil. I have downloaded the workshop manual, Looks like I will need to pull the engine to replace the head. and I will need to find a resource to tell me how to set the valve lash. Probably need head bolts and exhaust manifold studs to be safe.
Update, i replaced the head gasket, head bolts, exaust studs and all other gaskets I needed. Relaced all ruber fuel lines from tank to return. Starts and runs out perfecrly. Retorqued head bolts after 30 min heat cycle. Has 15 hours on it so far after repairs, runs strong and cooler than it has since i bought it in 2019. Thanks for all the input and advice.