Zetor 3011 new gearwheel

[Renze]

some photos of my recently bought 3011:
After i took it home, i found that the 4th gear made a noise like flick-flick-flick
Closer inspection showed that a teeth of the 4th gear is missing.
I need to pull it apart in 3 to remove the gear from the transmission layshaft.

Photo 1 shows the first split, between engine and clutch. You can see the dual steering rods that are taken off, and the dual clutch setup.

Photo 2 shows the tractor split in 3, with my brand new 2 ton shop lifter. I bought it for this job and i love it. The more because it was only 115 Euro

Photo 3 shows the pinion shaft sticking out of the rear axle. When i pulled the tranny off, the gearwheel of the reduction gear slipped off this shaft and was loose inside the transmission.

Photo 4 shows the loose reduction gear, when the pinion shaft is pulled out through the hole.
This is the back end of the gearbox, where the hi/low reduction gears are.
Maybe you can see a splined piece of shaft sticking out the back of the transmission, which can be seen through the upper shaft hole: Its for the ground speed PTO, to connect the PTO shaft to the reduction gear layshaft.

 

[MJPetersen]

Renze,

How is your project going? Are you getting it back together now? That is a major surgery. I am curious how it is going. Are parts hard to find for the Zetor? Nice shop lift -- I am thinking of making myself one, but have not yet. Other things are taking priority.

Mike

 

[Renze]

Mike,

For 115 Euro you cant build one yourself. If you buy the steel, the paint, the wheels and the hydraulic jack in different stores, the fuel you need to collect the parts would be more than the profit margin of the chinese companies that make these lifts

Zetor parts are very easy to find, even for this 1967 model: most parts are still produced, or the parts from newer models can be exchanged. Over the years they produced more than a million of these, and there are lots of aftermarket parts.
In India, they still build these models under license.
Our dealer bought an old cheese factory across the road, rebuilt it into a large facility with storage, workshops, farm warehouse and showroom.
Their old premises is loaded with a couple of dozens of tractors waiting for wreckage, their old workshop is full of parts and their old showroom is full of restored tractors.


.....I was just going to upload some more pictures: Last weeks i was too tired to do anything, because my daily job is so stressfull these days: The trailer business is so busy that there is a market shortage: We need to do miracles to get axles and tires on time, commercial customers could understand that but private customers think of buying a trailer as it was ordering a Happy Meal.... they dont understand that the axles simply arent there.. When you explain that, they ask, then why dont you take another supplier ?? Usually i dont take the time to explain that different axles arent in our type approval, that this would need individual brake calculations etcetera, etcetera...

Point is that they make everyone crazy, i spend 80% of the day making phone calls trying to buy axles from other manufacturers unused stock and get barked at when i have to inform customers that the axles for their trailers have been delayed for 8 weeks....

Anyways, the pictures:

picture 2 shows the internals of the clutch bellhousing:

picture 3 shows it after the clutch shaft, and throwout bearing have been taken out. I had to go to the hardware store first, to buy some pliers to take off the lock rings (Seeger rings)

picture 4 shows the internals behind the figure 8 shaped bearing carrier plate.
The main PTO gearwheel is already loose in the transmission because i pulled out the long PTO shaft with endpiece, from behind. Behind that plate i found inbus (inner hex) screws, which meant that i headed to town once more, to buy inner hex sockets, because these bolts couldnt be reached with normal inner hex wrenches.

picture 6 shows the first compartment (PTO gears) completely disassembled. The PTO gear is loose, and it can be taken out from above, after i take out all the shift forks at once.


All shafts and bearings came out easy, after some taps with a light hammer.

Next step will be machining a special gear puller to take out the high and low range layshaft from behind. the shop manual has a picture of a special tool, but i cannot get it through my trade contacts.
Which means i have to machine it myself.

The dealer said that in 90% of the cases, a broken gearwheel happens at 30 to 40 year old tractors, when the shift mechanism gets worn and they are put in 2 gears at the same time at full speed, which winds up the transmission. the forces that occur from an instant stop, have to go somewhere and usually result in a gear tooth that breaks off.
The other 9.99% of the broken gears is due to a bolt of the gear selector mechanism that isnt secured with the locking sheet, and drops between the gears.

 

[Renze]

I have some updates:

this afternoon i was at the point that i couldnt go on without special tools:
I drove around at some companies in the neighbourhood, where i normally can use the workshop in exchange for a crate of beer for the saturday evening company drink.
I couldnt use a lathe, so i decided to fiddle something with 3 different sizes of pipes.


First picture shows the expanding shaft puller: I used some pipe that fitted tightly over an M16 threaded rod. Over the end, i welded an extension piece of the next size of a 2 or 3 inch long. On the end, i welded a ring of another piece of pipe.
In the mid pipe i drilled 4 holes, then used the hand saw to make slots from the end into the drilled holes.
I put the assembly over the M16 threaded rod, put a wheel nut with its cone side towards the saw cuts and locked the last nut by a tack weld.
When i tighten the nuts, it presses the pipe over the cone side of the wheel nut, expanding the ring into a groove inside the shaft.


picture 2 shows the shaft expander inside the reduction gear layshaft, and also the other tool i made: Its just a piece of C-channel, drilled in the center, and with some supports welded at the ends.
When i tighten the nut against the C-channel, i can pull my expander puller, together with the layshaft assembly, out of the gearbox.


picture 3 shows 2 filler pieces, because i had to pull the bearing and the big gearwheel off the shaft while they were inside the transmission: you need to remove the shaft, bearing and small gear through the back plate, but the big gearwheel through the upper opening.
This required quite some force, and whilst tightening the puller nut, i allmost rolled the gearbox off its supports.


Picture 4 shows the complete puller assembly, still expanded into the rear of the reduction gear layshaft.

... Its like a photo of the calf that lies directly behind the cow after a tough birth...

 

[Renze]

Are parts hard to find for the Zetor?

I just ordered a brand new gear... they are still available, no Indian fake, but OEM Zetor quality...

 

[Renze]

When attempting reassembly, after cleaning the parts, i found that one bearing was suspicious.
After i requested a price quotation from my trade contact in Slovakia, who sells right off factory (no middle men, dealer and importer) i ordered ALL NEW transmission bearings, for about 150 Euro incl 40 euro mail cost. The gear wheels were also available.

 

[Renze]

Update on this one:
Its nearly 2.5 years later, i have had engine liners, pistons etcetera in the cabinet for a couple of months, but this summer i took the next stage in making this tractor brand new:
I put in the new liners and pistons, bearing wear was less than 0.05mm so i keep those, and now i'm waiting for a new rear engine cover (of the later models, with gufero seal instead of screw type, dust-eating and sweating "seal" ) so i can put my crankcase together, hang the flywheel and clutch behind it and build it back into the tractor.

I had the valve seats re-ground at a classic car repair shop, and have also ordered brand new valves. The brake cylinder also failed, so i ordered cylinders, brake lines, brake shoes and parking brake bands too.

...If those guys at the classic car repair shop arent too expensive with sheetmetal rolling, i'll order them to do the mudguards too... All i can find are Ursus or HMT mudguards, those will fit too, but because i am rebuilding it from the ground up, i dont want to waste it with imitation mudguards...