We flushed the radiator last weekend but haven't been able to get back to it to see if the oil is getting to the radiator still. You said the oil has to be under pressure, but isn't there a frost plug behind the gear cover that could be the culprit. The gears there are just splash lubed aren't they? Or am I just totally off? Will a pressure test show me anything here?
Oil in coolant and coolant in oil
- Thread starter Mx5000
- Start date
BAP
Well-known member
Lifetime Member
Equipment
2012 Kubota 2920, 60MMM, FEL, BH65 48" Bush Hog, 60"Backblade, B2782B Snowblower
Usually in an engine, you have coolant running around 12-15 psi. The oil runs at least 30-60 psi. Therefore, usually if there is a problem with coolant and oil mixing, the oil pressure pushes it into the coolant. Now this isn’t always 100% the way it happens, but gives you a start on tracking down the problem.
Let's talk about the oil cooler with the two male barbs.
Hose up that guy to an air compressor. In between put in a gauge and a shutoff valve (gauge on the oil cooler side). Pressure it up to about 40 psi and turn the shutoff valve.
Give it some time and see if the pressure goes down.
If you were working on this for someone else, you would try to minimize the parts changing. Since this machine has a known problem, and you are working on it for yourself, I would take the savings from buying a known dud and invest my time and money making sure that all has been done to bring this to a functional machine. There is a good chance that this machine has been overheated. When you get the head off, you can not only look for cracks but also the condition of the piston heads and valves. That may seem like extra work but the machine sale was discounted to cover that.
Hose up that guy to an air compressor. In between put in a gauge and a shutoff valve (gauge on the oil cooler side). Pressure it up to about 40 psi and turn the shutoff valve.
Give it some time and see if the pressure goes down.
If you were working on this for someone else, you would try to minimize the parts changing. Since this machine has a known problem, and you are working on it for yourself, I would take the savings from buying a known dud and invest my time and money making sure that all has been done to bring this to a functional machine. There is a good chance that this machine has been overheated. When you get the head off, you can not only look for cracks but also the condition of the piston heads and valves. That may seem like extra work but the machine sale was discounted to cover that.
North Idaho Wolfman
Moderator
Staff member
Lifetime Member
Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
I'm sorry this is a REALLY BAD suggestion, the input and output (two male barbs), on this system under normal working conditions would only see 15PSI max, it's just water.
If the unit was bad it would be pumping oil out of it as that would be much greater potential than the water side of it.
I'm figuring that the oil cooler is a simple heat exchanger with metal between the two medias.
Why the two barbs are floating without being hooked up is a mystery.
I would think that you are correct that if there is a leak between the two media then it would be leaking out the barbs.
If 40 psi is too high, then drop to 15 psi. My opinion is that the pressure will not drop once the shutoff valve is set to a closed system, there is not a leak in the heat exchanger. But it can easily be proved one way or the other.
And then move on to the more likely gasket and cylinder head.
Why the two barbs are floating without being hooked up is a mystery.
I would think that you are correct that if there is a leak between the two media then it would be leaking out the barbs.
If 40 psi is too high, then drop to 15 psi. My opinion is that the pressure will not drop once the shutoff valve is set to a closed system, there is not a leak in the heat exchanger. But it can easily be proved one way or the other.
And then move on to the more likely gasket and cylinder head.
Don't even know if this applies here; but a long time ago I was working on an old Ford 3910 and the heat/cooling system for the cab turned out to be the culprit. Easy fix because there was an isolator valve. Generally we don't need heat or cold here and the system had not been used for years and had rusted through.
Not sure but I think the owner before me bypassed the oil cooler to check to seel if it was the culprit
Does oil spewing out from a removed dipstick during engine operation indicate a frost plug. I read on the forum labeled "found oil in your coolant" and it says during a cooling system pressure test if the dipstick is removed and oil gushes out the frost plug is the culprit
It's with the engine off and pressure pump at the radiator cap, coolant would be displaced if it had a place to go through, which could be a missing or dislodged freeze plug. And if it were in a place where coolant and oil were close and the plug were between them, the coolant would push against the oil causing oil to move out the fill tube.
If the oil is pressured by exhaust gas from a bad gasket or cracked cylinder head would that give the symptom of oil spewing?
Did the previous owner ever use only water and not antifreeze?
Was there ever a prolonged period of subfreezing temperature?
Most of the freeze plugs are on the cylinder head. I don't know if on your model there is a freeze plug back around the water pump. However, getting access to the cylinder head will let you inspect those freeze plugs. And if you have any question as to their integrity, the cylinder head can be taken to a shop to have them pressure test the head.
If the oil is pressured by exhaust gas from a bad gasket or cracked cylinder head would that give the symptom of oil spewing?
Did the previous owner ever use only water and not antifreeze?
Was there ever a prolonged period of subfreezing temperature?
Most of the freeze plugs are on the cylinder head. I don't know if on your model there is a freeze plug back around the water pump. However, getting access to the cylinder head will let you inspect those freeze plugs. And if you have any question as to their integrity, the cylinder head can be taken to a shop to have them pressure test the head.
As of right now we are no longer getting water in the oil. Just oil in the coolant. Did a pressure test. Had an extremely slow leak, probably 1 psi every 2 minutes. When cranked the presume did build up about as slowly. I am assuming this means that I am starting with the head and working to the block.
update: finally got some time to work on the tractor. Got the head off and plugged off the oil port to the valves. Then pressurized the oil port and watched the beautiful bubbles come out of the water jacket holes. Did a quick check of the block by pouring water in the water jacket and putting air back into the oil port nozzle and nothing. Bad head it is. Really glad it was not the block. Thanks for all the help