MF 12 baler plunger bearing change: how to do it please!

richardlc

New User
I can't find anyone to explain how to change the plunger bearing on a MF12 baler! Is there a simple trick to it? It is difficult to get the baler to a workshop in this remote area.
 

The one on the plunger? You have to remove the plunger head out of the back of the baler.
 
(quoted from post at 03:38:18 02/02/18)
The one on the plunger? You have to remove the plunger head out of the back of the baler.
Many thanks: no the bearing is the one on the main crank assembly: it connects the crank to the front end of the connecting rod of the plunger. In the Massey parts manual it is called the connecting rod bearing. It is apparently easy to remove. I have bought a replacement bearing but can't figure out the easy way to change it with the old one. As MF design is so good there must be a fairly quick way for this routine service/repair job when that bearing fails or wears out, which it can do with fairly catastrophic effect, according to a now deceased friend! I have already undone the bearing block and am now figuring out the next step. I miss being able to yarn with him about the old machine!
 
(quoted from post at 03:38:18 02/02/18)
The one on the plunger? You have to remove the plunger head out of the back of the baler.
Many thanks: no the bearing is the one on the main crank assembly: it connects the crank to the front end of the connecting rod of the plunger. In the Massey parts manual it is called the connecting rod bearing. It is apparently easy to remove. I have bought a replacement bearing but can't figure out the easy way to change it with the old one. As MF design is so good there must be a fairly quick way for this routine service/repair job when that bearing fails or wears out, which it can do with fairly catastrophic effect, according to a now deceased friend! I have already undone the bearing block and am now figuring out the next step. I miss being able to yarn with him about the old machine!
 
The service manual does not have a specific section about that bearing. Between looking at mine, the parts manual and the service manual I think you would need to do the following.

1. Main drive gear: remove plug and drain oil.
2. Turn plunger crank arm, on end of main drive gear, to its extreme down position. Remove nuts and bolts clamping the arm onto the main drive gear shaft.
3. Remove the cap screws securing the main drive housing outer cover, remove cover and shim pack.
4. withdraw ring gear carrier, with ring gear (riveted to carrier). The carrier has the spline shaft that the crank arm is clamped on.
5. After removing the retainer clip, you should be able to remove the crank arm from the bearing.
 
Thank you very much! Yes I found the same instructions in my service manual, for servicing the gear box, and wondered whether there is a simpler solution, such as taking off the chain cog and shifting its axle inward to then tilt it off the axle: it has a curious looking slot on the end that may allow it to be tilted in this way. (I haven't checked all the clearances yet.) I was hoping that there might be a way of avoiding the heavy operation of shifting the gear box. I remember that the mechanic who changed my old friend's bearing did it in the field: sadly I couldn't stay to watch! Many thanks again for taking the trouble to reply. If I solve it simply I shall post the result.
 

Many thanks for the query: I have managed to do it and took photos of all stages. I shall post the solution shortly!
 
(quoted from post at 17:29:55 04/09/18)
Many thanks for the query: I have managed to do it and took photos of all stages. I shall post the solutin shortly!

Just checking, i need to replace the bearing, just curious if can post the pictures, or how to do, thank you for any information you can provide.
 
(reply to post at 05:04:54 04/13/18)
have now finished the description and will try to post photos but will have to check file sizes for photos and find out how to do so. Please let me know if there any problems. Unfortunately my post was not allowed because illegal symbols were included. I deleted all spaces etc but still not allowed so will try another way of copying it from the word processor which is Libre Office Writer. The photos I am not sure can be uploaded.
 
Here is another try at the description.
?Massey Ferguson 12 Baler plunger connecting rod crank bearing change.

1) Place Pick-Up in transport position to allow easy access to main chain sprocket.
2) Rotate flywheel anti-clockwise while facing front of baler, until main plunger crank is in full down position.
3) Make sure packer forks are supported in position to stop rotation of packer crank when main chain sprocket is removed.
4) Unbolt connecting rod bearing block from connecting rod assembly.
5) Loosen main drive chain assembly idler bolt and tap upwards to slacken main chain.
6) Scribe or mark main chain sprocket, cap screws and main chain in at least two places to ensure correct timing on replacing sprocket and chain. Remove cap screws, sprocket and chain from right end of machine drive crank assembly. On my MF12 baler there is a sprocket plate/hub here unlike the parts manual for the MF10 model which has a sprocket hub and coupling set up.
7) Remove cotter pin and washer from crank assembly.
8) Remove 4 bolts from machine drive crank bearing housing assembly.
9) Tap or press machine drive crank assembly to the right until it is free of the main plunger crank.
( A Home made press was made from one and a half inch galvanised nipple and socket fittings placed between the two cranks with a hardwood spacer, and expanded by unscrewing.) Remove washer from journal of crank assembly.
10) Rotate flywheel anti-clockwise to bring main plunger crank to vertical position.
11) Remove snap ring bearing retainer from connecting rod assembly: pull or tap connecting rod bearing and its bearing block from main plunger crank assembly.
12) Rotate old bearing in bearing block and slide bearing out of bearing block groove. Slide new bearing into position in bearing block, and push onto crank journal. Side old bearing between the new bearing and the press to help support new bearing in correct alignment.
13) Rotate flywheel anti-clockwise so that plunger crank is parallel to the ground, facing forward.
A home-made bearing press was made from two sets of fittings used in (9) above, the thread of the left socket was ground down to fit the journal. Place home-made bearing press in position, between right wall of baler chamber and bearing, with a hardwood spacer as necessary, and press bearing home on journal by unscrewing the socket from the nipple and vice versa as needed to lengthen the fitting and push the bearing onto the journal.
Old bearing is removed. Replace snap ring bearing retainer. Replace washer.
14) 4 bolts (7/16 x 2”) hardened steel are screwed through machine drive crank bearing housing assembly, ( see (8) above) to engage with bolt hole threads in the plate inside wall of bale chamber. These are screwed in evenly to pull machine drive crank bearing housing assembly back to the left and in to place, making sure that the rectangular hole in the machine drive crank assembly is aligned to connect with main drive crank journal. The long bolts are removed and replaced with original short (7/16 x 1 – 1/8” ) bolts which were removed in (8) above.
15) Replace washer and cotter pin on crank journal.
16) Fly wheel is rotated anti-clockwise so that crank is vertically down and bearing block bolted in place on the plunger connecting rod end.
17) Main chain and sprocket are bolted back in place making sure timing scribe marks match with original positions.
18) Tap idler sprocket assembly back in to position to tighten main chain as per handbook.
19) Check and adjust timing of plunger and packers, following manual instructions.
 
(reply to post at 05:04:54 04/13/18)
ere is another try at the description.
?Massey Ferguson 12 Baler plunger connecting rod crank bearing change.

1) Place Pick-Up in transport position to allow easy access to main chain sprocket.
2) Rotate flywheel anti-clockwise while facing front of baler, until main plunger crank is in full down position.
3) Make sure packer forks are supported in position to stop rotation of packer crank when main chain sprocket is removed.
4) Unbolt connecting rod bearing block from connecting rod assembly.
5) Loosen main drive chain assembly idler bolt and tap upwards to slacken main chain.
6) Scribe or mark main chain sprocket, cap screws and main chain in at least two places to ensure correct timing on replacing sprocket and chain. Remove cap screws, sprocket and chain from right end of machine drive crank assembly. On my MF12 baler there is a sprocket plate/hub here unlike the parts manual for the MF10 model which has a sprocket hub and coupling set up.
7) Remove cotter pin and washer from crank assembly.
8) Remove 4 bolts from machine drive crank bearing housing assembly.
9) Tap or press machine drive crank assembly to the right until it is free of the main plunger crank.
( A Home made press was made from one and a half inch galvanised nipple and socket fittings placed between the two cranks with a hardwood spacer, and expanded by unscrewing.) Remove washer from journal of crank assembly.
10) Rotate flywheel anti-clockwise to bring main plunger crank to vertical position.
11) Remove snap ring bearing retainer from connecting rod assembly: pull or tap connecting rod bearing and its bearing block from main plunger crank assembly.
12) Rotate old bearing in bearing block and slide bearing out of bearing block groove. Slide new bearing into position in bearing block, and push onto crank journal. Side old bearing between the new bearing and the press to help support new bearing in correct alignment.
13) Rotate flywheel anti-clockwise so that plunger crank is parallel to the ground, facing forward.
A home-made bearing press was made from two sets of fittings used in (9) above, the thread of the left socket was ground down to fit the journal. Place home-made bearing press in position, between right wall of baler chamber and bearing, with a hardwood spacer as necessary, and press bearing home on journal by unscrewing the socket from the nipple and vice versa as needed to lengthen the fitting and push the bearing onto the journal.
Old bearing is removed. Replace snap ring bearing retainer. Replace washer.
14) 4 bolts (7/16 x 2”) hardened steel are screwed through machine drive crank bearing housing assembly, ( see (8) above) to engage with bolt hole threads in the plate inside wall of bale chamber. These are screwed in evenly to pull machine drive crank bearing housing assembly back to the left and in to place, making sure that the rectangular hole in the machine drive crank assembly is aligned to connect with main drive crank journal. The long bolts are removed and replaced with original short (7/16 x 1 – 1/8” ) bolts which were removed in (8) above.
15) Replace washer and cotter pin on crank journal.
16) Fly wheel is rotated anti-clockwise so that crank is vertically down and bearing block bolted in place on the plunger connecting rod end.
17) Main chain and sprocket are bolted back in place making sure timing scribe marks match with original positions.
18) Tap idler sprocket assembly back in to position to tighten main chain as per handbook.
19) Check and adjust timing of plunger and packers, following manual instructions.
 
(quoted from post at 04:16:55 04/28/18) Here is another try at the description. This did not work either:sorry about that!
It worked twice despite being rejected, sorry about that. I shall upload one image of the bearing case being pulled back into place as a test. I that works a photo of the home made bearing press in use.
15630.jpg
15631.jpg
 
I am not sure whether you were helped by my solution. I am trying to upload here a diagram from the parts manual that shows at the arrow labelled "E" where the bolts are that need to be undone to shift the bearing housing labelled "2" to the right so as to free up the crank labelled "1" from the plunger bearing pinion.



mvphoto21658.jpg
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top