Hello everyone.
I’m having a strange problem with the engine in my T1600H, which I believe is a z482.
I have found a few posts here and elsewhere on the internet of people having the same problem with the same engine and other Kubota engines, but never any solutions or follow up.
I have not had it too long, bought last year but only started using this season.
Before I purchased the mower the engine had been rebuilt (bored, with oversized pistons), new gaskets, etc- I don’t have any real documentation, just receipts for the parts, the previous owner is a professional diesel mechanic, but not local so I can’t get him to look at it.
It starts easily, runs well, no smoke, plenty of power, doesn’t overheat, doesn’t use/lose coolant.
After running not very long and operating speed (5-10min maybe) it will suddenly spew a lot of oil out of the breather pipe, about a 1/3-1/2 litre, then it will stop loosing oil and continue to run normally, except that if I open the valve cover it is full of oil still, just no longer overflowing.
After this happens if I shut it down, the oil immediately leaves the valve cover and drains down as it should.
It’s about a 2.5l capacity system so there should be 1.5 +/- litres still in there, after it overflows it doesn’t register on the dipstick.
I have mowed with it a few time (I know that could be bad...), but it ran great, no overheating, no loss of power, didn’t run out of oil, just lost the 1/2ish litre once after starting out (I have the breather going to a catch can)
I have done an oil and filter change, checked and adjusted the valves, checked the breather filter (it was very clean), removed the push rods and checked all the passeges for obstructions, poured oil in each passage quickly to see if any of them drained slowly (they didn’t).
When I pull the dipstick while running oil spurts out, but not much different than my B6200 does, and the dipstick itself doesn’t ever pop out on its own, so there can’t be that much pressure built up in there.
I have run it with the valve cover removed, and it quickly fills the push rod passeges with oil after running for a bit at partial throttle, if I drop it to idle it drops down and doesn’t overflow, if I rev it up it will quickly rise again.
I haven’t done a compression test yet, (I have a compression tester, but none of the fittings are right for this engine, which I found out after removing the injectors), but I thought if the rings were bad or it was compression related it would be hard to start, and it starts easily hot or cold.
One suspicious thing I did find was foil from an oil jug in the valve cover, maybe something else could be in there blocking a deeper passage?
The guy I bought it from said he thought the ‘rings hadn’t seated yet’ and I should continue to use it, varying the speed and load, and to use oil additive due to ‘low ash content’ in modern oil- I don’t know anything about that.
There is no hour meter, but I estimate I’ve run it less than 10hours, and I don’t believe it was used much after the rebuild before I got it.
Does anyone have experience with something like that, or any advice as to what I can try?
Thanks
Ben
I’m having a strange problem with the engine in my T1600H, which I believe is a z482.
I have found a few posts here and elsewhere on the internet of people having the same problem with the same engine and other Kubota engines, but never any solutions or follow up.
I have not had it too long, bought last year but only started using this season.
Before I purchased the mower the engine had been rebuilt (bored, with oversized pistons), new gaskets, etc- I don’t have any real documentation, just receipts for the parts, the previous owner is a professional diesel mechanic, but not local so I can’t get him to look at it.
It starts easily, runs well, no smoke, plenty of power, doesn’t overheat, doesn’t use/lose coolant.
After running not very long and operating speed (5-10min maybe) it will suddenly spew a lot of oil out of the breather pipe, about a 1/3-1/2 litre, then it will stop loosing oil and continue to run normally, except that if I open the valve cover it is full of oil still, just no longer overflowing.
After this happens if I shut it down, the oil immediately leaves the valve cover and drains down as it should.
It’s about a 2.5l capacity system so there should be 1.5 +/- litres still in there, after it overflows it doesn’t register on the dipstick.
I have mowed with it a few time (I know that could be bad...), but it ran great, no overheating, no loss of power, didn’t run out of oil, just lost the 1/2ish litre once after starting out (I have the breather going to a catch can)
I have done an oil and filter change, checked and adjusted the valves, checked the breather filter (it was very clean), removed the push rods and checked all the passeges for obstructions, poured oil in each passage quickly to see if any of them drained slowly (they didn’t).
When I pull the dipstick while running oil spurts out, but not much different than my B6200 does, and the dipstick itself doesn’t ever pop out on its own, so there can’t be that much pressure built up in there.
I have run it with the valve cover removed, and it quickly fills the push rod passeges with oil after running for a bit at partial throttle, if I drop it to idle it drops down and doesn’t overflow, if I rev it up it will quickly rise again.
I haven’t done a compression test yet, (I have a compression tester, but none of the fittings are right for this engine, which I found out after removing the injectors), but I thought if the rings were bad or it was compression related it would be hard to start, and it starts easily hot or cold.
One suspicious thing I did find was foil from an oil jug in the valve cover, maybe something else could be in there blocking a deeper passage?
The guy I bought it from said he thought the ‘rings hadn’t seated yet’ and I should continue to use it, varying the speed and load, and to use oil additive due to ‘low ash content’ in modern oil- I don’t know anything about that.
There is no hour meter, but I estimate I’ve run it less than 10hours, and I don’t believe it was used much after the rebuild before I got it.
Does anyone have experience with something like that, or any advice as to what I can try?
Thanks
Ben
