Hydraulic fluid in my crankcase. Help please.

[Marlowe]

Hi folks.

My new to me little tractor, a Mitusbishi 1801, let me down today. The wife and I were trying out the bush hog and it needed a few adjustments. While I was trying to figure out what to do the engine started smoking, sputtering, and such, so I shut it down. Prior to that the engine ran fine, but the front end loader had progressively become slower and slower. I wondered if the two problems were related.

After a bit of head scratching, I decided to check the oil level.
When I pulled the dip stick, oil ran out. I'm smart enough to know that's not a good thing, so I checked to find where the excess oil may have come from. The only thing I could find low was the hydraulic fluid.

Now the fun began. I couldn't run the engine like it was, and I needed to put in back on the trailer to take it home. Of course it was pointed in the wrong direction and the land isn't cleared enough for me to get the trailer in front of it. We had to turn the little guy around by hand with a front end loader attached, and a bush hog. Then I loaded it with a come along. I think my wife now hates my tractor, and I'm not sure how she feels about me.

Now for the questions. I found the pump mounted on the left side of the engine. I assume it has some gear drive mechanism off the engine to power the pump. There must be a seal of some kind to keep the engine oil separated from the hydraulic oil. I had over two gallons of hydraulic oil in the crankcase, so whatever seal there is, isn't working. If I have guessed right so far, is there anyone still with me that knows what to look for? A gasket, or a seal? Or am I way off base here?

By the way; it was nearly ninety degrees today and the lot I'm clearing has no shade to speak of. My redheaded wife is now seeing red. I need to get this little issue straightened out quick.

Thanks folks.

Tom

 

[strokerduster]

you're on the right track. usually an oring seal from the crankcase. probably a reseal kit to repair pump.

 

[bobbyjak]

Are you sure it's not diesel fuel?..I had this problem on a large Case tractor where the glow plug unit got hung open and was dumping too much diesel into the cylinders and the excess was going into the oil case..The engine was running terrible..Could wash your rings out if you try to run it much in that condition..

 

[Soundguy]

Do check the diesel issue.. but the hydro pump dumping oil into the crankcase is not a new thing...very common failure mode when the shaft seal goes.

Soundguy

 

[SkyPup]

If it is diesel fuel contaminating the crankcase oil, you will be able to smell it very easily and distinctly.

 

[Marlowe]

I first suspected the diesel fuel issue, but I was not missing any from the fuel tank. I had about two gallons of extra fluid in my crankcase. I also had a chemical expert on hand; I let my wife smell the mix, then smell the hydraulic fluid alone. She assured me it was hydraulic fluid, not diesel. I never argue with the wife.

Thanks for the replies. I'll look into the pump this evening and report back. Someone else may find my findings interesting future reference.

 

[leslie428]

Understand your wife issue, mine is like that, she runs hot and cold on the tractor, loves it when it does her gardening, hates it when I use it for other things. Let us know how your hydraulic oil got into the crankcase. Very interesting!

 

[Jstpssng]

My Kubota had the same problem... it was a $5.oo seal in the hydraulic pump that cost me $150 in labor. Not a big deal though for a good mechanic. (He also wouldn't touch it until I bought a service manual.)

 

[Marlowe]

Okay folks, I found the problem. It was indeed a bad seal on the input shaft to the pump. Now to find one and put it all back together. The pump itself turns out to be a fairly simple gear type with bushings on each side of the gears. It appears to have been a recently installed two lipped seal that went bad. It looks like the inside lip was snagged on the shaft and cut during installation. It's amazing that such a small thing can cause such a big problem, but when I come to think of it, there are so many small things that any piece of machinery depends on to function as it should it's amazing that they work so dependably. Beats the heck out of a shovel.

Thanks again,

Tom

 

[mygoatboy]

I had the same problem with a Ford 3000 but it was the power steering pump. It ended up being a $20 shaft seal, not an o-ring. The seal was easy to do.