MF135 - Rearend Noise?

[dustyz]

Tractor newb here... so please be considerate. ;-)

My wife and I just picked up a nice chunk of land, and I needed something to bushhog about 5-10 acres, grade the driveway, and plow/till the garden when needed. I found this 3 cylinder gas MF135 on craigslist for a good price, comparatively:



I have a relative who also has a a 135, and he said this one is in much better shape than his, and he paid more for it. I couldn't go wrong... I thought.

It starts great. It runs fine too, when it warms up. It's a little hesitant when giving it more throttle or putting it under a quick load, it likes to cut out. A quick pull on the choke will get the RPM's back up. It's either a carb or fuel quality issue, since it sat for a while before I bought it.

The real problem is the "clank" noise I hear in the rearend. It only happens when I'm in a higher gear, 2 or 3, in high range... and when the tractor is twisting one direction. Strange, I know. If I'm in 2nd H, and turning left, the rearend will clank maybe once every rotation of the tire. I can almost feel it in the seat, so I'm pretty sure its internal. If I go over an incline that twists the front end a little, it will do it to. Turning right, or keeping the tractor in Low gears does not have the same results.

Any immediate things to check? Thanks! (I've already pulled the manuals, thanks to those who shared!)

 

[ch1ch2]

No ideas here.
But they are easy to work on. Don't be scared to try it your self.

 

[Jerry/MT]

Tractor newb here... so please be considerate. ;-)

My wife and I just picked up a nice chunk of land, and I needed something to bushhog about 5-10 acres, grade the driveway, and plow/till the garden when needed. I found this 3 cylinder gas MF135 on craigslist for a good price, comparatively:

View attachment 465628

I have a relative who also has a a 135, and he said this one is in much better shape than his, and he paid more for it. I couldn't go wrong... I thought.

It starts great. It runs fine too, when it warms up. It's a little hesitant when giving it more throttle or putting it under a quick load, it likes to cut out. A quick pull on the choke will get the RPM's back up. It's either a carb or fuel quality issue, since it sat for a while before I bought it.

The real problem is the "clank" noise I hear in the rearend. It only happens when I'm in a higher gear, 2 or 3, in high range... and when the tractor is twisting one direction. Strange, I know. If I'm in 2nd H, and turning left, the rearend will clank maybe once every rotation of the tire. I can almost feel it in the seat, so I'm pretty sure its internal. If I go over an incline that twists the front end a little, it will do it to. Turning right, or keeping the tractor in Low gears does not have the same results.

Any immediate things to check? Thanks! (I've already pulled the manuals, thanks to those who shared!)

Sounds like a problem with the differential if it happens only when you turn in one direction. The inside wheel on the turn move slower than outside wheel so there may be a bad bearing in the differential. Open the side access panel, jack it up, block the left wheel so it can't turn, start it up and put it in gear and observe the differential action. BE CAREFUL THAT THE TRACTOR DOESN"T SLIP OFF THE JACK! GET ANOTHER PERSON TO SIT ON THE TRACTOR TO SHUT IT OFF IN CASE IT DOES.

 

[BobG_in_VA]

This may sound funny, but check the tightness of the lugnuts on the rear wheels. If one is loose every time it goes around it will "clunck". Jack up the rear and put it in neutral...spin the wheels and see if you get the noise. Take an impact/lugwrench and torque down on the lugs...hopefully, the sound will go away. PS: if you can feel it in the seat, it can also be a lug nut... BobG in VA

 

[TomSeller]

Differential lock pedal releasing okay?

 

[dustyz]

Latest first, Tom, I'm pretty sure my 135 doesn't have a diff lock. There's no sign of it, and I've had a few local farmers look it over too. They said it probably doesn't. I helped pull another tractor out of a creek a few weeks ago, and I had to play the brakes to keep traction. (I wish it did have it.)

Bob, the lug check will be easy enough. I will check those this weekend.

Jerry, that sounds a little in-depth. I might grab a local to help with that process. Is there a panel or plate that could easily be removed to inspect the rearend?

I've been a little nervous using it with the noise, but I've had several people tell me it's fine. Since I won't be using 2-High range, which is when the popping happens, it likely won't cause any problems. Still, I'd like to identify the problem before taking the risk.

Thanks for the help!

 

[Arc weld]

I know if the bushing is worn on the front axle will cause the fan to hit the shroud if a front wheel drops in a hole and/or the tractor twists a bit. Once every revoltion of the wheel? Could you have the PTO in ground speed and it's causing the noise? The PTO has ground speed, neutral and engine speeds. Ground speed PTO turns once for every 20 inches of forward travel. How do the brakes work?

 

[dustyz]

I know if the bushing is worn on the front axle will cause the fan to hit the shroud if a front wheel drops in a hole and/or the tractor twists a bit. Once every revoltion of the wheel? Could you have the PTO in ground speed and it's causing the noise? The PTO has ground speed, neutral and engine speeds. Ground speed PTO turns once for every 20 inches of forward travel. How do the brakes work?

The brakes work really really well. They are solid, and stop it on a dime. The noise doesn't sound like a fan, it sounds like something big and heavy. I initially thought the width adjustments on the rear wheels were loose, and as it was in a bind they'd slip a little and cause it to pop. It's that kinda noise.

I'll check the PTO, but I think that would make the noise all the time, and not just when turning or twisting the tractor. Thanks for the info, more for me to inspect.

 

[Arc weld]

Maybe it is the power adjust wheels? The brakes might cause it if they were adjusted tight or something. Most older 135's don't have the greatest brakes.

 

[redman135]

Hello Dustyz, Diff-lock pedal, look on the right side foot plate at the back, there will be a 3rd pedal there if you have a diff-lock. In your photo the right brake pedal is in the way. I have never seen a 135 without diff-lock before.
Also check the PAVT rim bolts. My father had a 178 that would go clunk intermittantly when a bolt worked loose(not the hub).