MF135 transmission housing leak

[jleonardwv]

Bought this MF135 in May and used it a few times with a box blade. I knew it had some leaks when I bought it. I'm investigating the leaks now.

Leak #1. Someone drilled a hole in the bottom of the transmission housing? See photo. As I wiped the grime off the bottom of the transmission housing, I see a hole that seems to barely leak, maybe a drop every five minutes. So I curled up a piece of paper towel and stuck it in the hole to absorb. My thought was that perhaps it was formed as part of the housing and the moisture just got trapped in there over time, but when I stuck the paper towel piece up in there, it started gushing and clearly the hole goes all the way through!

Is that normal?

The fix I can think of is to put threads in the hole and plug it with a bolt. The photo shows fluid like motor oil dripping out, but the fluid seems to be a mix of transmission fluid and motor oil.

 

[Birdhunter1]

It is a weep hole, the clutch is inside that housing, it is a dry clutch and any fluid that gets in there needs to get out. It is a hole from the factory, it is not uncommon for fluid to leak into there, it is normal for it to drip out like that (at least on a tractor 50 years old or more).

 

[jleonardwv]

It is a weep hole, the clutch is inside that housing, it is a dry clutch and any fluid that gets in there needs to get out. It is a hole from the factory, it is not uncommon for fluid to leak into there, it is normal for it to drip out like that (at least on a tractor 50 years old or more).

So I don't plug the hole, but if it's dripping motor oil and transmission fluid does that mean something internally needs a new seal/gasket?

 

[Birdhunter1]

Yes. if you have a puddle overnight that looks like a dog peed then you might want to replace whatever seal is leaking, if it is a few drops overnight or there is a drop ready to fall off the belly of the machine almost all the time I wouldn't worry about it. To repair it will involve splitting the tractor in half and separating the halves to gain access to whatever seal will need replaced. If you can't do that yourself then get ready for a large labor bill. Your best bet will be to keep checking fluids and adding oil as needed.

 

[jleonardwv]

This seems like sound advice. The leak from the transmission housing is maybe a drop or two a day but I will monitor it some more.

Someone said it could be the gasket from the oil pan that is allowing this to leak. if so is it a hard job to replace that gasket? I'm getting ready to change the oil and filter anyway.

 

[murphy1244]

This seems like sound advice. The leak from the transmission housing is maybe a drop or two a day but I will monitor it some more.

Someone said it could be the gasket from the oil pan that is allowing this to leak. if so is it a hard job to replace that gasket? I'm getting ready to change the oil and filter anyway.

There is no oil pan. You should order a owners manual as it is full of good info.

 

[redman135]

If the oil is clear it is coming from the gearbox. If the oil is black it is coming from the engine.
A few drips are nothing to be concerned about. Just get in the habit of checking the dipstick( engine and trans') before using the tractor for peace of mind, and fill as required.
The engine oil culprint will be the rear crankshaft seal. It is a major job to replace this seal. Fitting the seal is tricky for first timers too. Been there, sloowly did that.Took several tries to compress seal to fit.

 

[PatrickS2222]

If the oil is clear it is coming from the gearbox. If the oil is black it is coming from the engine.
A few drips are nothing to be concerned about. Just get in the habit of checking the dipstick( engine and trans') before using the tractor for peace of mind, and fill as required.
The engine oil culprint will be the rear crankshaft seal. It is a major job to replace this seal. Fitting the seal is tricky for first timers too. Been there, sloowly did that.Took several tries to compress seal to fit.

For both seals ... Been There, done that too!
A little-known fact: In tractors with a dual-clutch, there are actually two front seals in the gearbox ... because there are two input seals! If you reckon the crankshaft seal is difficult to renew ... and they can be sometimes ... the best advice regarding the gearbox front seals, is don't take them on! The second input shaft is tubular, for the PTO and hydraulic pump drive, with a seal inside it sealing it to the main gearbox input shaft, and another seal outside it, sealing it to the gearbox casing. There are various ball-race bearings and needle-roller bearings to really complicate things! The design overall is very impressive and looks very strong. Bearings are all 6208-series, most are high-load, and last decades. I believe the same basic gearbox design is used in various other models, up to MF188s.
A small oil leak is nowhere near a problem in a 50y/o tractor - just ensure the vent hole is clear and the oil levels are kept correct.
Look after it and enjoy driving it. That's what I do with our 135 and 40.

 

[jleonardwv]

Thanks. That provides me peace of mind.