oil in water kubota b6000

scoobynova

New member

Equipment
b6000
Oct 12, 2012
8
0
0
ireland
hi there could any body help me please i have recently done the head gasket in my kubota b6000 i got the head skimmed and pressure tested and fitted a genuine head gasket but now i have noticed thart there is water in the oil again would it be possible that there could be a cracked liner ?id be greatful for any help
 

Stumpy

New member

Equipment
L175
Dec 1, 2011
848
3
0
NE Ohio
A cracked liner wouldn't cause coolant in the oil. These engines use dry liners pressed into cast iron bores. It's possible you've got a crack somewhere in the block or head but there's no easy way to diagnose that without removing the head and doing a dye penetration test unless you know someone with an ultrasound crack detector. Another possibility is the freeze plug under the cam gear cover. It can pop out or loosen and let coolant drain into the crankcase from the jacket. Unfortunately it's not visible without removing the case and that's quite a bit of work. It's a shot mostly in the dark but it beats a cracked block or head.
 

scoobynova

New member

Equipment
b6000
Oct 12, 2012
8
0
0
ireland
Thanks very much for your reply matt im going to start striping the crankcase off it tonight , i wasnt sure if the liners wer wet or not so thanks for that it eliminates that for me any way , the guy that done the head for me pressure tested it so im pretty sure that the head is fine it never over heated on me so i was at a loss to figure out what is wrong would it be a strange place to put a plug at the back of a crankcase any way ?
 

Stumpy

New member

Equipment
L175
Dec 1, 2011
848
3
0
NE Ohio
Hold up before you do a bunch of work, it looks like I may be wrong. I'm leafing through the parts diagram for your machine. The diagram for my machine shows a plug under the gear cover while your's does not. I see 5 casting plugs in the parts diagrams, 4 on the head and 1 on the back side of the block, but that one is exposed. There is an oring that seals a water neck (passes coolant from the lower water neck to the block through the cam gear cover) under that cover that could be the culprit but I don't see the casting plug.

Does coolant leak without pressure in the cooling system? If so take off your oil pan and fill it up and watch where the coolant is coming from. If it's coming from the gear case you'll see it coming from the oil return ports in the front of the block. If I'm really wrong it'll be dripping from somewhere else.
 
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scoobynova

New member

Equipment
b6000
Oct 12, 2012
8
0
0
ireland
thanks guys i held off stripping it tonight i was driving it for an hour on saturday last and it was going very well i checked the oil and water and they wer perfect then i started it monday for a few minutes and checked it and the water level had droped and of course the oil was milky , this morning i topped up the rad again and checked it this evening and id say the water had droped maybe half a cup during the course of the day
 

scoobynova

New member

Equipment
b6000
Oct 12, 2012
8
0
0
ireland
ok i took the oil pan off the tractor tonight and pressurised the radiator and got underneath the tractor and i can see water droping between the liner and the block right at the bottom of the cylinder nearest the radiator would this mean a cracked block ?
 

lsmurphy

Active member

Equipment
B7001
Oct 19, 2012
1,197
5
36
Parrrottsville TN
ok i took the oil pan off the tractor tonight and pressurised the radiator and got underneath the tractor and i can see water droping between the liner and the block right at the bottom of the cylinder nearest the radiator would this mean a cracked block ?
Yep, I would think so.
 

Stumpy

New member

Equipment
L175
Dec 1, 2011
848
3
0
NE Ohio
Unfortunately yeah sounds like a cracked block. You can tear it apart and any good engine shop oughta be able to pull the liners out and repair it for you but if you can find a good engine or parts tractor with one that might be the way to go, depends on the new engine.
 

scoobynova

New member

Equipment
b6000
Oct 12, 2012
8
0
0
ireland
thanks for all your help guys im just in the middle of striping it down now i took the head off it this evening , it looks like there is wet liners in it to me ?? would i be lucky enough to pull the pistons up out of it and pull the liners up and is there some kind of copper gasket or o ring sealing it to the bottom of the block perhaps ??
 

Stumpy

New member

Equipment
L175
Dec 1, 2011
848
3
0
NE Ohio
My apologies it appears I may be wrong again. To the best of my knowledge Kubota uses dry liner construction in a majority of their engines, especially the older 70s vintage stuff, but looking at your parts diagrams again I see two protrusions from the liners labeled Packing, Cylinder Liner. Those could very well be the seals for a wet liner. Pull the liners and tell us what you find.
 

lsmurphy

Active member

Equipment
B7001
Oct 19, 2012
1,197
5
36
Parrrottsville TN
My apologies it appears I may be wrong again. To the best of my knowledge Kubota uses dry liner construction in a majority of their engines, especially the older 70s vintage stuff, but looking at your parts diagrams again I see two protrusions from the liners labeled Packing, Cylinder Liner. Those could very well be the seals for a wet liner. Pull the liners and tell us what you find.

I considered that as a possibility myself.......not looking at any reference materials...........

What if the block bore is out of round? cracked? eroded? May he be back to where he is after spending $1700 or so?
 

scoobynova

New member

Equipment
b6000
Oct 12, 2012
8
0
0
ireland
im going to pull the liner up tomorow guys to see whats the story my only fear is that maybe the block could be badly eroded which would make it difficult for the o ring or if its a copper gasket to seal properly again
 

Stumpy

New member

Equipment
L175
Dec 1, 2011
848
3
0
NE Ohio
I considered that as a possibility myself.......not looking at any reference materials...........
If you think I'm wrong speak up! :) No one is infallible though I seem to be making more of a fool of myself than usual. Again I had it in my head that dry liners were generally what Kubota used. Leafing through my I&T manual I see many of them are dry liners (L175-185, L225-235-245-275-285-295, L305-345-355 and the B5100-6100-7100), but there are a few wet liners (L210, L260) and that's just what my book covers. I should've checked first, twice in this case. My apologies again.

What if the block bore is out of round? cracked? eroded? May he be back to where he is after spending $1700 or so?
The guy who installed and honed the liners in my block he straight up told me he's never had a block in his shop he's had to scrap. He told me if it's cracked they've got an annealing furnace big enough for tractor trailer engines so they can preheat, weld them, and then normalize them. If the parent bore or liner seats are worn they can build it back up with welds and then rebore it to size. Now is that cost effective on something like this? Depends on the damage and the shop. There's no way of knowing till you've opened it up and looked inside and let the shop have a look at it. For the right price a whole engine swap might make sense but if it was only a little cheaper than a rebuild I'd take the known quantity over a used engine.
 

scoobynova

New member

Equipment
b6000
Oct 12, 2012
8
0
0
ireland
hi guys ok i stripped the engine any way pulled the pistons up out of it and pulled up the liner that is leaking , there is 2 o rings that are machined into the block at the bottom , but i found it 2 be quite rusty inside there i think the previous owner was just running it on water only , im going to give it a good clean down fit 2 new o rings and maybe some sealer aswell just to make sure it seals correctly , but im very happy theres no cracks in the block or liner this was a very difficult problem to diagnose i will fit new big end bearings etc now when its all open .
Id like to thank every one for your help with this