MF35 Locked up (z134)

[shaeff]

Ugh.

So here's the scenario-

I was using the flail mower to cut down some tall grass, cut some paths through my field. Was running the machine for maybe 1.5-2hrs. Temp gauge never moved, oil pressure good, radiator full, and clear of debris, oil is full.

I noticed it was starting to feel low on power, like when I'd get into tall grass it would bog down and the governor wouldn't pull the RPM back up. I disengaged the flail and was just going to bring it back up to the house. As I'm moving up a small grade in 3rd low, it started to bog even for that. I shut it off immediately at that location out in my field. The machine sat there overnight. I went out the next morning to fire it up, it turned a tiny bit and just stopped. The starter still works fine, but when it engages the flywheel it binds up tight.

Here's the information to know:
- it's not the starter
- I can normally spin this motor (z134) by hand off the fan when in neutral. I cannot.
- I tried to spin it over by the crank pulley. I cannot
- I tried to bar it over off the flywheel. It's stuck, It won't move.
- I tried a huge adjustable wrench off the PTO shaft on the flail with the PTO engaged, it will not move.
- The plugs look great, it was running beautifully prior to this
- No oil or coolant in the cylinders
- I can't see anything concerning in the cylinders with an inspection camera, but the camera I'm using isn't that great.
- I removed the front mounted hydraulic pump (MF35 Utility with a loader on it), the pump spins freely
- I can spin the PTO by hand when it's disengaged
- The machine tows fine in neutral, rear wheels spin freely.

Is my next step to pull the head? Any other suggestions before I go that route? It *could* use a valve job, so I'm not opposed to pulling the head. I already have the hood and gas tank removed for better access.

The thing that gets me, it was running when I shut it down. Now it's stuck. I'd think that it would at least turn by hand. The motor didn't feel hot either.

Open to suggestions. Hoping it won't need an in-frame kit, but if it does, I'll do it.

Thanks

 

[MTGreen]

I think a key piece of information here is that you can't get the PTO to move which leads me to believe that it may not necessarily be the engine, especially when you know it's not hydrolocked because you looked in the cylinders and chances are low that your pistons rod and crank bearings are seized if the engine didn't get hot and the oil doesn't smell burnt. I'm wondering if there's something to do with the clutch locking up to the engine or something else in the drivetrain. You could try seeing if there's an inspection plate in the clutch housing and have somebody actuate it while you look with your camera to see if the clutch is functioning correctly. You could also pull the tractor in neutral with another piece of equipment and see if the rear tires turn or skid

 

[shaeff]

I think a key piece of information here is that you can't get the PTO to move which leads me to believe that it may not necessarily be the engine, especially when you know it's not hydrolocked because you looked in the cylinders and chances are low that your pistons rod and crank bearings are seized if the engine didn't get hot and the oil doesn't smell burnt. I'm wondering if there's something to do with the clutch locking up to the engine or something else in the drivetrain. You could try seeing if there's an inspection plate in the clutch housing and have somebody actuate it while you look with your camera to see if the clutch is functioning correctly. You could also pull the tractor in neutral with another piece of equipment and see if the rear tires turn or skid

Edited the first post to include more info:

I can get the PTO to move if it's disengaged. It spins freely by hand just like normal. The clutch disengages normally, I did check that under the inspection plate. The machine also tows fine in neutral, I just had a buddy of mine steer it out of the field while I towed it and the rear wheels spin freely with no binding. I'm fairly certain the issue is engine related.

It's been suggested on another forum that maybe it spun a rod bearing and when I shut it down it just stuck.

 

[MTGreen]

Edited the first post to include more info:

I can get the PTO to move if it's disengaged. It spins freely by hand just like normal. The clutch disengages normally, I did check that under the inspection plate. The machine also tows fine in neutral, I just had a buddy of mine steer it out of the field while I towed it and the rear wheels spin freely with no binding. I'm fairly certain the issue is engine related.

It's been suggested on another forum that maybe it spun a rod bearing and when I shut it down it just stuck.

Makes sense. Good luck!

 

[redman135]

hmmm that sounds familier.
Did the engine sound clatter just before you turned it off?
When you tried to start the next day, did the engine screech then sieze?
It sounds like you may have run a bearing shell.

If you have run a bearing shell, then by turning the engine off you may have saved your self a big bill. It is still a major job as you will need to remove the engine (WEDGE the front axle so it does not flop over) and pull the crank (tractor sumps are VERY HEAVY, mind your toes) Best case you only need to polish the crank and replace the bearing shells.

I had this problem on my MF135. The extra metal on the crankshaft came from the bearing and the crankshaft itself was undamaged, just a polish job I was told.
Since you have to split the tractor check the clutch and espesially the pilot bearing as well.

Reassembly tip to mate engine and gearbox, (for 6 and 8 sp gearbox) engage pto and as you bring the 2 halves togather, have an assistant rotate the pto to line up the splines with the clutch, and it goes in easily (does not work with multipower gearbox).

 

[shaeff]

Engine sounded fine before shutting it down. No odd noises or anything. In fact, it was idling perfectly fine too.

When I went to crank it over a good 18hrs later, it sounded like it turned a tiny bit and stopped. Another forum I'm on (YT) one of the guys there suggested the same- spun bearing. I was hoping to avoid all that, but if it needs a rebuild, there's no better time than this winter to tear it down. The key is to get the motor in my basement and on an engine stand before the snow flies. I'm aware of the potential for the front to flop over without the axle wedged, but thanks for the reminder. If I end up having to pull it all apart, I'll be replacing the leaky rear main seal, checking the clutch for oil exposure from that leaky seal, tidying up everything that needs it.

Thanks for the tip on the PTO trick, that'll be helpful.

 

[Jerry/MT]

Ugh.

So here's the scenario-

I was using the flail mower to cut down some tall grass, cut some paths through my field. Was running the machine for maybe 1.5-2hrs. Temp gauge never moved, oil pressure good, radiator full, and clear of debris, oil is full.

I noticed it was starting to feel low on power, like when I'd get into tall grass it would bog down and the governor wouldn't pull the RPM back up. I disengaged the flail and was just going to bring it back up to the house. As I'm moving up a small grade in 3rd low, it started to bog even for that. I shut it off immediately at that location out in my field. The machine sat there overnight. I went out the next morning to fire it up, it turned a tiny bit and just stopped. The starter still works fine, but when it engages the flywheel it binds up tight.

Here's the information to know:
- it's not the starter
- I can normally spin this motor (z134) by hand off the fan when in neutral. I cannot.
- I tried to spin it over by the crank pulley. I cannot
- I tried to bar it over off the flywheel. It's stuck, It won't move.
- I tried a huge adjustable wrench off the PTO shaft on the flail with the PTO engaged, it will not move.
- The plugs look great, it was running beautifully prior to this
- No oil or coolant in the cylinders
- I can't see anything concerning in the cylinders with an inspection camera, but the camera I'm using isn't that great.
- I removed the front mounted hydraulic pump (MF35 Utility with a loader on it), the pump spins freely
- I can spin the PTO by hand when it's disengaged
- The machine tows fine in neutral, rear wheels spin freely.

Is my next step to pull the head? Any other suggestions before I go that route? It *could* use a valve job, so I'm not opposed to pulling the head. I already have the hood and gas tank removed for better access.

The thing that gets me, it was running when I shut it down. Now it's stuck. I'd think that it would at least turn by hand. The motor didn't feel hot either.

Open to suggestions. Hoping it won't need an in-frame kit, but if it does, I'll do it.

Thanks

I had a ring gear come off my TO-30 and wedge between the flywheel and the bell housing and it locked the engine up. The engine was a Z129 and it turned out someone put a flywheel from an early production TO-20/Z120 engine on it. It turns out the early TO20's had the ring gear sweated on from the rear. Every time the starter drive hit the ring gear it was trying to push it off the flywheel and it eventually would.
Ferguson changed the design by sweating it on from the front and machining a ring at the back to prevent the starter from knocking it off the fly wheel. I still have the ring gear and the old flywheel and the ring gear was tack welded on to the flywheel. the tack welds were not strong enough.
The other issue is that the electrical system was converted to 12V and the original 6 V starter was used. The addition torque of the starter contributed to the problem.

The fix was to find a re-designed flywheel (which I did) and install that. No more problems.

That's a long way to tell you to remove the starter and look at the ring gear to make sure it is still on flywheel.

 

[shaeff]

I had a ring gear come off my TO-30 and wedge between the flywheel and the bell housing and it locked the engine up. The engine was a Z129 and it turned out someone put a flywheel from an early production TO-20/Z120 engine on it. It turns out the early TO20's had the ring gear sweated on from the rear. Every time the starter drive hit the ring gear it was trying to push it off the flywheel and it eventually would.
Ferguson changed the design by sweating it on from the front and machining a ring at the back to prevent the starter from knocking it off the fly wheel. I still have the ring gear and the old flywheel and the ring gear was tack welded on to the flywheel. the tack welds were not strong enough.
The other issue is that the electrical system was converted to 12V and the original 6 V starter was used. The addition torque of the starter contributed to the problem.

The fix was to find a re-designed flywheel (which I did) and install that. No more problems.

That's a long way to tell you to remove the starter and look at the ring gear to make sure it is still on flywheel.

That’s pretty wild! I did get around to pulling the clutch inspection plate. The ring gear is still on the flywheel. Can’t spin it from there either.

 

[Jerry/MT]

That’s pretty wild! I did get around to pulling the clutch inspection plate. The ring gear is still on the flywheel. Can’t spin it from there either.

You might want to look from the starter end. As I recall I had to look pretty hard to find that the ring gear was "out of plane".

 

[5030]

Sounds like a dropped valve to me.