Blowing Oil Out The Top End Vent Tube

[chieffan]

Got the 7100 out today. First time it really ran much since I rebuilt the injectors and worked on sealing a crack in the block. Ran it up the road for 1/4 mile and back and noticed it was spitting oil out the vent tube, along with some smoke/fumes. Mrs. took it up and back and by the time she got back is had quit spitting out the oil but still had the smoke.
Being completely new to Kubota and diesels in general is this something to be concerned about? Possibly overfilled the oil? I know it is natural for gas engines to emit some fumes out the breather pipe so figure diesels were the same. Would over filling the oil cause this to happen? I put 4 quarts of 10-W40 in when it was changed.

 

[85Hokie]

How many hours on the ol girl....not the Mrs........the tractor
But seriously - did this EVER do this before?
and what does the dipstick read now, now that it burped some out?

I would let it cool off good and then fire it up again .....see if it repeats the same problem. My 7100 barfs some smoke on startup and if the light is right I can see fumes all the time.

 

[chieffan]

How many hours on the ol girl....not the Mrs........the tractor
But seriously - did this EVER do this before?
and what does the dipstick read now, now that it burped some out?

I would let it cool off good and then fire it up again .....see if it repeats the same problem. My 7100 barfs some smoke on startup and if the light is right I can see fumes all the time.

750 on the hours. Just getting it running after setting 2 years with a small crack in the block - little water in the oil but I think I have the issue taken care of. Between the owners manual and service manual there is about a quart difference in the amount recommended. One says 3.3 l the other says 4 quarts. I put in 4 quarts.

 

[coachgeo]

If it keeps happening then you may have another crack allowing compression to get into the valve cover...... or a valve issue.

How much engine refresh did you do along with the correction of the crack you mention.

 

[North Idaho Wolfman]

Pull off the valve cover and start it up, and see where the excess smoke is coming from. Betting both out of the valve guides and out of the oil return holes (bottom of the engine, hence rings).

Not to be Debbie Downer, but I'm pretty sure that you keep throwing cups of water on a forest fire!
A cracked block in a Kubota diesel can't be fixed by a little sealer in the radiator.
These engines have such tight tolerances, a crack throws everything off.

If you have a crack that's between the cylinder wall and the cylinder sleeve, every time it heats up and cools down it will move.

Get either a new Block or a a completely new motor!

 

[chieffan]

I knew when I bought the tractor that it had a crack in the block. I figured I would have to replace the block at some time. Also figured it don't hurt to try a less expensive fix first. If it don't work only out a few bucks and a little time. New is out of the question as I would have as much in the new block as the whole tractor and deck is worth. It's real easy to tell someone 'you have to have new' when they are not writing the check. Thanks for the info. With 750 hours I doubt the valves or guides are the problem. From what I have seen these engines will run a lot longer than that before anything needs rebuilt.

 

[Tooljunkie]

What does oil level on dipstick read?
May need to drain a little out.

Sea foam in fuel may help with sticky rings.
A little blow is normal. An engine that has been sitting
Will exibit this sort of thing.

 

[chieffan]

Thanks Tooljunkie. I was thinking possibly the rings could be stuck fro sitting for that 2+years. Yesterday was the first time I got it good and warm since getting it running. The plug on the dip. stick was loose also so went by the manual and put 4 quarts in and adjusted the plug and fixed it in that position. Oil was full before I started and coolant at the same level as when it was parked over a month ago.Will let it sit for a few days and check the oil again. Might drain a 1/2 qt. out and see what happens. Thanks for the info. I appreciate it.

 

[North Idaho Wolfman]

When I said new I meant new to you!

 

[chieffan]

Thanks Wolf Man. That does make a BIG difference. Been trying to locate a used one but no luck yet. Is the d750a the only engine that will fit in that tractor? I know the 4 cyl are to long, and the 2 cyl are probably short on power for the 5' deck. To get a short block and use my parts with new rings is pushing the total value of the unit but might be doable.

 

[skeets]

You could start to look here and go from there,, lots of places on line, and I think there are several other motors you can replace it with ,,wolfman would know for sure

https://countrysalesandservice.com/industry/agricultural/

 

[D2Cat]

Last summer I was looking for a similar engine just in case I needed to replace the one in my B7100 that I got with the head off, radiator missing and I did not know the condition of the engine.

I found some from a shop who imported them from Japan. They were low hours engines out of rice combines. He was located South and East of here, like Memphis. But I didn't need one. Cost was $1000 (I think).

If you can't find something, or would like, I can go through my notes and probably find a number.

 

[chieffan]

Checked the oil yesterday morning. Showed down about 1/2 way between full and add so going to see what it does when I use it next time. I have run into that before that an engine likes to run 1/2 - 1 quart low. Change oil and right away it starts smoking till it is down to the level it likes and stays there. Time will tell.