MF 135 Hydraulic 3 Point Hitch Questions

[termyte14]

Well it's been a while again. First was waiting on a few replacement parts, then decided to strip and paint areas that would be difficult to get to later (behind the draft response panel, underside of the draft control housing, etc.).

With respect to the position control cam, here is a photo of the cam installed the correct way.



This was quite an easy fix with the cover off and the cams exposed. I confirmed Big Dean's statement quoted above. In fact, with the quadrants removed, you have to rotate the rod that controls the position cam outside of its normal range to get it back in place. This was very easy and it actually happened a second time after I replaced the roller but I knew what had happened and in less than a minute, had it corrected. You just have to see and feel it in the right place.

Anyway, finally got the lift cover adjusted using the I & T manual and reinstalled. Then did the final adjustments through the draft response panel. The oil tube that comes up from the pump to the lift cover was rather difficult to get installed but I believe that was due to the tight machining in the pump. Hooked up a 7' light duty blade today and dragged the driveway. Seemed to work great, hadn't used the blade before as the bushhog was hooked up when I bought it but it lifted all the way up. At least until my neighbor came by and stood on the rear of the blade. It would not lift the blade with his additional weight (approximately 200 pounds). He got off and it would lift it fine. I'm guessing it won't do well with the bushhog or a recently acquired Ford 201 flex-o-hitch disk.

I am open to any suggestions as to how to get the three point hitch to lift more weight. I contacted the dealer about adjusting the lift cover and making the final adjustments and was told it would be time and material at $85/hour. He also said it could take 2 - 6 hours. Any thoughts on this?

Thanks, Michael

 

[termyte14]

Forgot to post a picture of the new vs. old hydraulic linkage pivot shaft. It actually is a two piece pin but there is a sort of brass snap ring that holds them together. The old one had a lot of slop in it.

 

[shona13]

G'day termyte14.
To complete the internal and external hydraulic adjustments requires that before beginning to adjust it is important that the Draft Spring is adjusted and functioning properly, read the it manual ,this will give you the necessary information.

To check the hydraulics , fit a heavy implement to the tractor then bypass the toplink that is install a chain or a load rated sling in place of the toplink and instead of connecting where it would normally fit ,connect it to the long pin just below,by doing this you are temporarily removing the draft control spring from the system, Repeat be very carefull ,if the tractor lifts the implement you will have to remove the draft assembly and adjust as per manual, most often this will require replacement of the parts inside ,you will know what i mean by the time you have finished.
happy Days.
Hutch.

 

[termyte14]

Thanks for the input Hutch. I had completely pulled down the draft control spring and adjusted per the manual. I will try hooking up an implement and connecting to the pin you refer to. I have a few questions though. You say to be very careful, what specifically do I need to be cautious about? If the tractor lifts the implement in this scenario, are you saying I will need to probably replace the parts within the draft control spring assembly or parts on the underneath of the cover? Hopefully I will have a chance to look into this issue this weekend.

Thanks again for the input.

Michael

 

[shona13]

G'day termyte.
As always I ask that when doing your own repairs that you be mindfull of all danger including that which may happen as a result of in this case the Temporary Chain or Sling breaking under load, keep children and adults well away from the posssible danger.

The draft spring adjustment:
Step one is to install a Hydraulic Pressure gauge , this will help you diagnose and locate the hydraulic problem .
The gauge can be fitted either into the front left hand side of the lift cover, remove the three eighth" npt allen headed grub screw and fit the gauge.
The gauge should be good for Three thousand PSI to be safe.

The draft spring if incorrectly adjusted will have an influence on the operation or otherwise of the Three point linkage ,to test with an implement attached ,one that will put a bit of weight on the toplink .

Remove the sideplate to give you access to the hydraulic control lever.

Set the Draft Lever in the UP position and for the moment leave it there.

Set The engine speed at about 900 to 1000 rpm then using the Position control lever slowly raise the implement and at the same time watch the draft spring and note the amount it "Stretches", pulls out,if adjusted correctly it should pull out about half an inch at most ,and lift the linkage all the way into the TRANSPORT Position if not, still with the Position control lever in the Transport position Look inside then Slowly move the position control lever Up and down watching what the control valve is doing, if you see the control valve moving Forward ,into the Neutral position BEFORE IT ACTUALLY REACHES THE TRANSPORT POSITION on the linkage ,Carefully with your fingers push the lever gently to the rear Forcing the control valve if you like ,if this gives you a favourable result you may if lucky ,be able to adjust the fine tune Knurled nut on the control lever if not let me know what results you get.
Happy Days.
Hutch.

 

[termyte14]

OK, I definitely understand the cautionary note. I'm going to have to try to find a gauge though. I'm hoping a local farmer may have one I can borrow.

Once I find a gauge, do I connect the implement as I would normally, or do I still bypass the top link?

I am familiar with the control lever and knurled nut you are referring to so I just have to find a gauge now.

Thanks again, Michael

 

[shona13]

G'Day termyte .
Yes ,try the hydraulics with the linkage hooked up as you would normally ,then do the same again with the temporary chain/sling and compare the results .
Regards.
Hutch.

 

[termyte14]

Ok, I got a 3000 psi gauge from Northern Tool. Got it installed today and did some testing. I have not drained any oil or removed the side inspection plate but here are my results.

I first checked the gauge without an implement attached to the three point hitch. The draft control lever is in the full up position and the position control is moved through the full range stopping at the transport position. The gauge reads 0 psi through the full range of motion. When the position lever is placed into the constant pumping position, you hear the relief valve begin to sound and the gauge jumped to about 2800 psi. I didn't get a picture because I didn't want to leave the system in this situation that long. Here's a picture of the set up.



Next I connected a bush hog as you normally would through the top link. The levers were operated in the same manner and the front of the bush hog wouldn't even come off the ground. The gauge barely came off 0 psi. Here's a couple pics:



Last I removed the top link connection and attached a chain from the top link connection of the bush hog to a bolt below the top link connection on the tractor. I operated the levers in the same manner and it raised the bush hog through the full range of motion. The gauge read about 700 psi with the draft control lever in the full up position and the position control lever in the transport position. Here are some pics:



Based on the above information, what is my next move? Any guidance would be greatly appreciated.

Thanks, Michael

 

[shona13]

G'Day termyte.
Excellent photographs.
So now we know the pump is o.k although the pressure is a bit high , should be around 2500 <>psi.

Remove the sideplate as suggested and with the toplink in the Normal operating position that is attached to the draft link , and again the draft lever all the way up, slowly raise /move the Position control lever towards and stop at the transport position watching what the control valve is doing ,if you find that the control lever is returning the control valve to neutral before the linkage reaches the transport position gently assist the control linkage and move the control valve to allow the pump to raise the implement, if this has the desired effect you will have to remove the draft link assembly ,the one with the big spring inside, remove complete and readjust when you are happy all is good with this part ,thoroughly clean out the housing and make sure the sensing rod inside is properly located ,that is it should be sticking out about 1/4 inch if all good reassemble and test ,you may have to adjust the compression on the spring to fine tune the controls, this is done by Tightening the big NUT behind the dust boot ,adjust say 1/4 turn at a time and test till you get a satifactory result.
Let me know the results and we can go from there.

Happy Days.
Hutch.

 

[aczlan]

What happened when you placed the lever in constant pumping with bush hog on the upper 3 point position (draft control)?

I agree that your pump is fine, you just have maladjusted linkage.

Aaron Z

 

[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