Oil Leak

Makeer

New member

Equipment
B6100E
Feb 18, 2013
11
0
1
Kentucky
Just bought a B6100E. A lot of old oil on the Woods 438 belly mower just under where what I would call the bell housing mates up with the back of the engine. Somewhere just above where the orange sheet metal starts, on the left side, sitting on the tractor, there is black oil leaking. Doesn't appear to be leaking when it isn't running and oil level on dip stick didn't change noticeably after mowing for about 45 minutes, but it sure made a mess on the trailer when I first picked the tractor up from the previous owner. I think that came off captive area on the mower where it had collected over time, when I backed it up the tailgate onto the trailer.

Story from previous owner was it had set for about 3 years with little use. It has a growling if you depress clutch and leave it in gear while running. From what I've read on here that's an indication of oil on the clutch.

Took it by our local Kubota dealer and he says it's the rear main seal. Saw a reply on here from Vic? to a guy asking about an oil leak on a 175 that stated "In my shop I've never seen a Kubota engine of any variant with a bad or worn rear engine seal and have replaced them only in the course of engine rebuilding." (04-20-2012, 09:17 AM RE: 175 Oil leak)

Found a mechanic that used to work at that dealer and he's quoting a $250-$300 price (labor) to replace the rear main seal.

Gentlemen, I'm a carpenter and 54 years old, I don't mind paying a professional to do mechanic work. I've messed enough stuff up over the years to believe they are worth what they ask. I'd like to be a bit more sure of the problem before I commit to the repair. I was ready to take it to him until I read that reply about rear mains rarely leaking.

I cleaned all the old caked up oil off and the leak seems to be high up, and running down the bell housing at that joint mentioned above. If I have it replaced, must the clutch be replaced as well? Except for the growling with the clutch depressed and still in gear everything seemed to operate well while mowing.

I've worn out a lot of riding mowers over the years and I was really tickled after mowing with this thing yesterday. Just like I've heard, it's a little tank!

Any advice would be most appreciated,

Lucky in Kentucky
 

Big Kahuna

Member

Equipment
Kubota 2000 L3010 HST with Loader ,1992 B7100HST , 1979 B6100E & 2007 F2880
Dec 23, 2011
368
9
18
Homer City, Pa.
Welcome, First thing I'd do is give her a good pressure washing if you can and clean her up, my 6100E dribbles oil onto the mower deck frame work for at least 15 years, it's really not as bad as it sounds. I pressure wash in the fall when I put it away and we are all clean again, why go looking for trouble over a little oil, it mows great all summer and I never add any oil.
As for the clutch, when you store for long periods Kubota supplied you with a wooden block to keep the clutch pedal down, I think your tractor just needs run and used and the growling will go away.
Yes they are tanks, that little 6100 has amazed me more times than I can remember, excellent tractor!:D
 

Stumpy

New member

Equipment
L175
Dec 1, 2011
848
7
0
NE Ohio
2nd the pressure washing, hard to tell where it's coming from under all that oil. $300 labor isn't bad considering he's got to split the tractor and yes the clutch the throwout bearing should be replaced anytime you've got the machine split. The labor of splitting the tractor is the expensive part of that job.

That said describe where you think it's coming from again. You say it's coming from higher up and running down the outside of the bell housing? The oil pressure switch is above the bell housing on the left side of the block (left from the seat) and I seem to recall someone else having a problem with that leaking. You can also tell if it's the rear main seal pretty easily. Right side of the bell housing there's a flywheel inspection plate\plug, remove that and see if the flywheel is oily. If not then the rear main is fine. There may also be a drain plug on the bottom of the bell housing.
 

hodge

Well-known member
Lifetime Member

Equipment
John Deere 790 John Deere 310 backhoe Bobcat 743
Nov 19, 2010
2,945
509
113
Love, VA
2nd the pressure washing, hard to tell where it's coming from under all that oil. $300 labor isn't bad considering he's got to split the tractor and yes the clutch the throwout bearing should be replaced anytime you've got the machine split. The labor of splitting the tractor is the expensive part of that job.

That said describe where you think it's coming from again. You say it's coming from higher up and running down the outside of the bell housing? The oil pressure switch is above the bell housing on the left side of the block (left from the seat) and I seem to recall someone else having a problem with that leaking. You can also tell if it's the rear main seal pretty easily. Right side of the bell housing there's a flywheel inspection plate\plug, remove that and see if the flywheel is oily. If not then the rear main is fine. There may also be a drain plug on the bottom of the bell housing.
I third cleaning it up real well, to better determine where the oil is coming from. If it is any higher than the centerline of the housing, then I doubt that it's the rear main. I would look for another source.
 

Orange Tractors

Member

Equipment
L175 w/Woods L59, Allis Chalmers WD
Jul 19, 2009
323
4
18
Butler, MO
I'll add a fourth to the pressure washing idea. It will be a lot easier to see just where the oil is coming from.

The oil pressure switch on my L175 leaked for years, a drip or two at a time, until it finally started really leaking. Something like $23.00 for a new switch and it doesn't leak anymore.

IF that is what is leaking, all it takes to replace it is screwing the old one out and the new one in. It does have British pipe threads not american or metric, so the chances of finding one at the local auto parts store are slim.

Robert
 

Makeer

New member

Equipment
B6100E
Feb 18, 2013
11
0
1
Kentucky
Thanks for all the advice and information. Finally had enough time and warm enough temperature to wash all the grease off the bottom half of the engine, just can’t bring myself to shoot a pressure washer onto the top and sides of the engine. I’ve not had good results doing that with gas engines in the past.

Is it OK to open the hood, cover the top and sides of the engine with cleaner and hose off a Kubota diesel?
Used cleaner and rags to clean up around the oil pressure switch at the back of the engine as recommended and that’s where it’s leaking, oh what a relief it is!!!

Local Kubota dealer couldn’t find a part number for the switch Saturday morning, but said they’d call someone Monday and get back to me. I downloaded the parts manual and couldn’t find it either but found a place online called Country Sales and Service that has one that supposedly fits a Kubota, doesn’t say if it fits one as old as a 6100. The part # is 15841-39010, $14.85 plus $13.00 shipping. Can anyone confirm that part number for a B6100 oil pressure switch?

I’m a little concerned about buying it off the net and something not fitting. I’ve been reading about British pipe threads in the block where the switch threads in.

Another interesting side bar. Read about adding a pressure gauge. There’s a place for it on the dash. But what will it take, part wise to accomplish this? Since the low pressure warning light is electrical wouldn’t the gauge take an oil sending unit at the block instead of a switch? If anyone has names and part numbers of what it would take I’d like to try it instead of just repairing the switch and light. To re-cap,.......

1. Advice on cleaning top and sides of engine.
2. Where to get proper part number for switch and light if I go back with
original configuration.
3. Comments, parts and numbers to add pressure gauge to dash. ( gauge,
sending unit, tubing???)

Having knowledgeable people that are so willing to help sure is a wonderful thing to those of us less mechanically inclined. Thank you, thank you, thank you!
Lucky in Kentucky
 
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Orange Tractors

Member

Equipment
L175 w/Woods L59, Allis Chalmers WD
Jul 19, 2009
323
4
18
Butler, MO
To clean the top of a Kubota, I would get some of the spray enginge degreaser and apply it to a warm, not hot, engine. Then spray it off. If your local car wash has an engine degreasing setting, the green colored stuf that comes out does pretty well.

I would cover the air intake with a plastic bag, no sense getting water inside.

Your part number came up as the correct one at http://www.colemanequip.com/ Their price was $17.61, and I don't know how much shipping and taxes would be.

Someone on here has teed in a fitting to run both the idiot light and a gage, but I don't remember who it was. The hardest part is finding the British to American or metric adapter; other than that, one of the oil pressure gage kits from an auto parts store will work.

Robert
 

tmessenger

New member

Equipment
B7100D P
Feb 17, 2013
40
0
0
Fairfield, IA
I just bough a 1979 B7100D the rear main seal was leaking (753 hrs on engine) the seal was blown out of the housing. This engine has almost no blow by and the crank vent is clear. The seal felt somewhat dried out but it is 34 years old. I'm replacing both the front and rear seals while I'm at it. I'm also replacing the clutch disk. I read on hear you never have to adjust the valves on these engines but I check mine and 5 of the valves were out (2) at .010 (3) at .009 the inside of the engine was spotless and it runs and starts perfect so best to check stuff out.

Tim
 
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Russell King

Well-known member
Lifetime Member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
6,112
1,865
113
Austin, Texas
Swagelok has adapters that are male straight thread (BSP) to screw in the block to a female NPT in the adapter to screw a fitting into. You can probably order them from McMaster Carr or Graingers. Don't forget that you will need a sealing washer (they are called Dowty washers in general)

http://www.swagelok.com/downloads/WebCatalogs/EN/MS-01-147.PDF

I have used a cleaner called Purple Power that works well but verify it won't harm the paint.
 

Makeer

New member

Equipment
B6100E
Feb 18, 2013
11
0
1
Kentucky
Finally warmed up enough to replace the oil pressure switch. Solved the leak! Many thank to all that replied. Haven't run it hard and long yet but just putting around and idling,... stays dry. Hurray!