Kubota L4150 - Water in Crankcase, Please help

[gwill26]

Hello,
I have a newly acquired L4150 with the 5 cylinder engine. The tractor is in rough shape cosmetically, but it was running great, so I decided to clean it up. I had no issues with smoke or steam when I ran it, it ran great. I had taken the radiator off and backflushed the cooling system with a garden hose. When I checked the oil, the crankcase had been filled with water. If I put air pressure in the cooling system now, I get oil (and water) out of the dipstick hole. It doesen't seem like a crack, too much airflow. The parts diagram shows what looks like a freeze plug behind the gearcase on the front of the block. Could this be my problem or do you guys think that this is as bad as I think it is? Are there any suggestions as to any other issues that would cause this condition? And lastly, can I get the gearcas off without pulling the motor?
Thanks in advance for any help,
Greg

 

[brain55]

Yes, it does sound like it could be the freeze plug behind the front cover, but it could also be one of the ones in the cylinder head. I would certainly pull the valve cover off first. I have seen the ones in the head pop out more often than the one behind the front cover.

Brian

 

[gwill26]

Thanks for the fast reply. Would the plugs to which you refer be visible when the valve cover is removed?
Thanks, Greg

 

[brain55]

Yes they are visible, the view might be a little obscured by the rocker arm shaft though.

Brian

 

[repete]

Curiosity, what was the process you used for the backflush? A garden hose can have as much as 100 PSI and if it cannot free flow through the system then the system can come well beyond the 14 PSI of pressure the cooling system normally operates under.

Did you connect the garden hose to the lower radiator hose then charge against a closed thermostat?

 

[gwill26]

Thank you Brian, you were correct. I had one plug popped in the head. It appears, looking at the rocker shaft, that this has been popped for quite some time. When I put the water to it, it certainly showed, filling the crankcase. I had not run the tractor much until this time, therefore it was not obvious to me. I assume that I should replace all of the plugs in the head at this time?
Thank you, you made my life easier.
Greg

 

[gwill26]

Repete,
When I backflushed, I put the hose into both top and bottom hoses with no clamp, just inserted, leaving flow out of the feed hose as well. In hindsight, I probably should not have done that. I believe, after pulling the valve cover, that this issue had been occuring for awhile, I just amplified it. That being said, do you think that I may have done further damage with the process that I used?
Thank you for the reply,
Greg

 

[brain55]

I have always just replaced the one freeze plug, and have never had one come back with another one blown out.

As far as causing any additional damage with what you did back flushing it, I doubt it. The most I would probably do is change the oil, get the machine up to operating temp for awhile and then change the oil again.

Brian

 

[gwill26]

Thanks Brian, if you weren't 3,000 miles away, I'd buy you a beer.

 

[brain55]

Glad I could help, I knew those twelve years working for Kubota dealers would pay off, lol.