MF 135 Hydraulic 3 Point Hitch Questions

[aczlan]

Found these which may be of interest to you:

Sorry I have been really busy and haven't had a chance (nor will I for several days) to work on it. I plan on removing the response control again and go through some of the steps from the manual and see what happens. I think I tightened that bolt up too much when I put it back together, I don't know. I will PM Hutch though. I need all the help I can get. Thanks

Just for reference, I snapped a couple pics of the pages from my manual that I was using.

Well, I don't know what it is I am doing wrong, but I have followed the instructions to the best of my ability and it seems that if the draft adjustment is right then the position adjustment is out and vise versa. So I thought I didn't care SO much about the draft if the position worked at this point. I adjusted the position out and re-installed the top cover. Now it's all out of adjustment, the 3 point will lift if the draft is as far back as it can go and you cycle the position lever a couple times. Anybody had any luck at adjusting these two points?

I did completely remove the top cover and invert it as the directions said. I thought everything else was as directed also, if I am mistaken please correct me...

Also: MF 135 hydraulic and pto problems - Massey Harris & Massey Ferguson

Aaron Z

 

[termyte14]

Got some decent weather today and no baseball tournament this weekend so I was able to hook the bush hog up again to test. Hooked it up as I normally would to the top link and removed the side cover. Got the tractor running a little over 900 RPMs. With the draft control lever all the way up, I started to raised the position control lever. When the position control lever gets to about the middle of the word "POSITION" stamped on the quadrant, the control valve retreats to neutral position and the lifting of the bush hog stops.



I was able to move the control valve lever toward the rear of the tractor and got desirable results (it lifted the bush hog all the way up). When I let go of it, it would stay in the fully raised position until I lowered the position control lever. When I lowered the position control lever and re-raised it, the bush hog again stopped raising when the lever got to the middle of the work "POSITION". I played with the knurled nut but was unable to get desirable results without manually controlling the pump. It would only raise the front of the bush hog off the ground about 3 - 3/4".

I guess I'll be digging into the draft control spring assembly next to readjust. Is this the correct next step?

Thanks again for all the help. Michael

 

[shona13]

G'Day termyte.
First of We got rain this morning ,first rain since september last year WoooHooo.

This all sounds good ,
I am not sure if you need help with adjusting the draft spring assembly but basically ,remove the toplink including the swivelling yoke, (two Allen headed Capscrews) then the big nut (undo the small locking grubscrew first).
(If the large dust boot needs replacing this is the time to do it).

I will mention that at this time If the internal adjustments have been carried out and the draft assembly was not properly adjusted prior it is/will have an affect on all other adjustments ,so lets see how lucky we are in this case .

With the draft spring assembly removed, If the spring has been tensioned properly you should be able to Rotate it by hand against the friction created by the spring being compressed remember if readjusting do not overtighten .

At this point
if the spring needs to be adjusted hook out the small 3/4 "rubber dust protector plug then knock out the small locking pin and adjust the rod as required, refit the unit to the tractor making sure the threads are clean and greased up this makes it easier to adjust the big nut, screw the big nut IN till all end play has been removed and Keep turning the nut till the draft link STARTS TO BECOME LOOSE AND RATTLE then undo the big nut again till everything is tight again start the tractor and try this ,you may have to put a little bit more tension on the spring ,Just a quarter turn at a time keep moving up and down till you are happy .

To test the draft sensing ,set the Position lever in the transport position and set the Draft lever BETWEEN the two Stamped Sector marks on the quadrant if all is good you should be able to go to the rearmost point of the Brushhog and raise and lower it by hand, if you find that it wont either raise or lower move the draft lever accordingly any movement away from the Draft reference lines indicates an out of adjustment ,this will not really matter so long as it is not to much out.

Happy days.
Hutch.

 

[The kid]

I have a few pictures of what Hutch is talking about. I have replaced some of those parts.

Here's the link in my thread.
Refurbishing my Z145 135 - Page 19
-kid

 

[termyte14]

I re-read the instructions for adjusting the draft control spring and I found some language that I missed the first time. Previously when tightening the plunger onto the clevis, I only tightened to the point of the end play being removed. It was quite easy to turn the spring on the plunger with this setup. I also had just barely tightened the larger nut that holds it all in place until the end play was just removed. With this information, I pulled the draft control spring and began to readjust.

I also found that I had put the big nut on backwards so I pulled it all apart and reassembled. I tightened the plunger up until I just could spin the spring by hand. Put it back in and tightened big nut until the end play was removed and then tightened some more.

Tried the position control lever and it lifted the bush hog off the ground and all the way up through the full range. However, if someone stands on the back of the bush hog, it will not lift the bush hog.

Do I now need to remove the lift cover again and readjust the draft and position adjustments again.

Hopefully someone will learn from my mistake here. Again, I appreciate all the help from this site.

Michael

 

[shona13]

g'day termyte 14.
Try adjusting the big nut ,say tighten one half turn.
Hutch.

 

[termyte14]

Okay, tightened the big nut another quarter turn before the end play came back. This helped a little but still won't lift the bush hog with 200 extra pounds standing on the back. It will lift the bush hog by itself. If I walk up on the bush hog while it is lifted with the tractor running, it leaks down after about 15 seconds. If I have the bush hog raised up and cut the tractor off, the hydraulics will support an extra 400 pounds on the rear of the bush hog and not leak down.

Did I maybe tighten up the yoke too much on the plunger bolt this time. The spring could be turned by hand but it was hard. It may have been more than snug as the manual stated. Once I get these adjustments close to right (with ya'lls help of course), I plan to remove the lift cover and carry out the internal adjustments again since this one was so far off. It's already much better than when I bought the tractor and much better than when I carried out the first adjustments after replacing the pump.

Any further advice on tweaking this draft control spring adjustment would be greatly appreciated.

Thanks, Michael

 

[shona13]

G'day termyte 14.
I did mention that you may /may not be lucky with this adjustment .

Before removing the liftcover try adjusting the fine tune wheel inside the gearbox , the one that runs in contact with the control valve roller apart from that you will have to remove the liftcover and redo the internal adjustments which if they are adjusted as per manual will give you :dance1:much happiness .
Regards.
Hutch.

 

[termyte14]

Ok so I took the lift cover off and readjusted the draft and position adjustments. I put the lift cover back on and reinstalled the roller. I feel the control arm is too close to the dashpot because after synchronizing control valve with the lift cover. With the position control lever in the transport position and the draft control lever between the quadrant marks, I cannot get the lift arms to begin to raise by screwing the knurled nut into the control arm. I have it screwed all the way in. I have been using a fish scale to pull 3 pounds on the control arm and setting the gap to 0, just where the control arm touches the dashpot plunger when fully extended. The lift control quadrants were double and triple checked to be in the correct position when making each adjustment. The lift arms were positioned by lining up the chisel marks I had made while the lift arms were in the transport position on the tractor.

Any thoughts? Could I have a slightly bent control arm? Can the adjustments be made using a lighter pull force? That would seem to put less tension toward the dashpot when the lift cover is installed. Again, any help would be greatly appreciated.

Thanks, Michael

 

[termyte14]

Forgot to ask a couple more questions. Is there a rule of thumb as to how many threads should be showing on the draft and position adjustment screws?

Thanks, Michael