Defeated by the Master Control Spring

fixt

Member
Massey Model 65 Diesel UNDM 704769

So how does this master control spring retainer nut come out?
No blue wrench available, plus I'm unwilling to cut something I don't have a replacement part in hand.

I removed the grub screw at 3 o'clock, the "special" cap screws, and the control spring retainer nut refuses to move after a couple of mighty whacks with a 4 lb hammer and a punch, and I let it soak for a while in penetrant as well. I'l have a new boot for it that I can't install. Such is life... maybe someday.
I don't think the pin spanner would hold up the beating on the wrench to get it loose. 54 years of rust says NO.

The play in the master control spring is about 3/16, maybe a little less. Considering I'm only going to bush hog and scrape the driveway, I'll just let it ride the way it is.

Its not gonna hurt anything is it?

Attacched spanner picture courtesy of DavidP,South Wales.
I blew it up a little and tried to sharpen it so you could read the dimensions better. It was way too small before.

mvphoto11932.jpg
 
Hello, my fame is spreading!!!! Removal of
the control spring nut can be a right pain
in the proverbial. If you have the peg
spanner or are able to make one you will
have to exercise caution in using a hammer
on it. Have you tried giving it a whack on
the rear face to loosen it? It is possible
to hit the inner splines with a punch to
start it moving. If you fail to move it it
is possible to drill several 1/4" holes at
an accessible point to weaken the nut and
then close it a little to loosen it. There
should be no problem obtaining non-genuine
parts as needed. Once you have removed the
spring that is the first part of the
problem. The second is seperation of the
yoke and plunger rod. This will probably
require heat. If you can get movement LEAVE
IT AT THAT until it is cold. It has a very
fine thread which will 'pick-up' and jam.
Work a penetrating fluid into the threads.
Don't forget to remove the groove pin
first. This must be seperated to renew the
boot and reset the spring pressure. When
the end-float increases the 3-point will
lift less and less. The play will tell the
control valve to stay close to 'neutral'.
Patience is the word to do the job.
DavidP,South Wales
 
OK, thank you. I did find one on flea bay... from India. The only ones there are from India, from 2 weeks to a month out.
I never thought about drilling on it to weaken the thingy. It looks like some pretty long holes to drill. It appears to be pretty robust thickness wise, though a fairly soft steel

I did pound on it with several rather severe whacks and a heavy punch; it never moved and began to deform, so I stopped before I regretted something.
 
Type in ...Massey ferguson 35 draft control lock nut removal - YouTube

Massey ferguson 35 draft control lock nut removal - YouTube

Pretty brutal.....however watch... Massey ferguson 35 draft control lock nut removal - YouTube


Bob....
 

I tried. All I get is a black screen with audio. I did hear the part where they cut the yoke off though, I presume to weld a tube of some sort on the nut. They did say all the internal parts were pretty much junk. Mine (at least as far as I know) are not, yet.
It sounds brutal too, what they were doing.

Maybe try some heat around the periphery and apply some penetrant. I've got some cold off penetrant stuff that seems to work decently. Maybe if I do that for a few days along with the drilling to weaken the nut before I start whacking on it
 
I've had to heat the outside of where the nut is, then while its hot go after the nut with a punch, and hammer. If the nut starts moving don't stop, once it gets easy to turn with the punch/hammer put the spanner wrench on it, and keep on going until its out.
 
That's kinda what I had in mind.
I'm going to heat the outside a few times and spray it with penetrant.
Then I'm going to heat the outside and spray the nut inside with freeze out and go at it with a 4 lb hammer and a big chisel/punch.

I've resigned myself to pretty much replacing most internals which are not as expensive as I thought. I'll be re using the spring, LOL. I think I'll cut the clevis off to get it out of the way while I'm banging away at it.
YT had all the parts I needed.
 
(quoted from post at 01:26:15 03/03/18) Hi, very unlikely as you will not have room
to turn it. It needs to be offset.
DavidP

I don't think I understand.
What do you mean by "needs to be offset"?
 
I've fought with those things until I was blue in the face, and with several quite red knuckles!

And after getting them out and several tries to save the plunger rod, said to hell with it and cut it midway so the back half can be held
more securely to get the back nut off with minimal damage to the threads.

As you've observed, those parts are relatively cheap.

On reassembly with the new rod and boot, I lube all threads with heavy grease and pack the back of the plunger rod hole with heavy grease
to make it easier for the next chap to replace the boot 40 years from now!! I think there used to be a rubber plug in that hole.
 

It's out!
I drilled a hole next to the spline that effectively cut the nut and didn't hit any threads. Applied heat around the outside, just enough for expansion so not a lot, and hit the nut with freeze off.
I started framming on it with a 4 lb and a big flat punch. It started turning and per ptfarmer I did not stop until it was out.
I cut the control spring plunger to recover the spring. Its soaking in diesel right now. There was lots of rust encountered in this evolution.

I never did see the small groove pin, or where it went. Unable to recover that. Probably have to make one of those out of a grade 5 bolt or something similar.

I still haven't been able to get the stop disc out. I can see the pin that goes through it and I tried a magnet but no luck. Been spraying brake cleaner in that bore and mopping it out.
[b:b1bd2727bc]Any suggestions on retrieving this thing? What is that pin for?[/b:b1bd2727bc]
 
Hi, the disc is only resting in place so
will come out easily if clean but it
probably has a build-up of rust around it.
The rod protruding through it is the Draft
rod. When adjusted correctly it transmits
compressive force signals to the internal
linkage to tell the pump to raise or lower
the 3-point if ploughing for example.
DavidP
 
You can actually see the stop disc from the linkage side of the disc. With the top inverted look at the draft control rod going out the back. there is a aproximately a 1 inch hole and you will see the back of the disc. I took a punch and knocked mine loose from there. As was said already it just sits there so it doesn't take much to knock it loose.
Did you cut the yoke off or not? I was able to reuse the one on my 65 but the one on my 50 was soo hard to get off that I ruined the threads on jt and had to get a new one. Not too bad price wise as well.I think if I ever had to do it again I think I would save the spring and the cup on the bottom and just replace the rest.

Steven
 

Thanks again tractor guru DavidP. My pin appears to be slightly mushroomed, but I can always file dress it a little. I'll check it for freedom of movement. I couldn't figure just what it did from the drawing

Hi Steven-Id
Thanks for that info.
I've been reviewing the parts assembly to how to get it out from the draft pin linkage side, but I didn't know the hole was that large.
That will make it pretty easy to knock loose.
I'm going to make a long extension for a small wire brush to get down in there to knock that muck loose and may hit it with some evap o rust. Plenty of grease on everything going back together and never seize where applicable.

I cut the yoke off so I could get a punch in there to get the retainer nut loose. I ordered a new clevis, spring cup, plunger, and stop disc from YT. They did not have the retainer nut so I'm stuck waiting on that from India, coming by a diseased yak I suppose.
I did get the clevis bushings out for reuse. Those things are really in there.
 
Don't forget about the boot too. If yours is like mine it never came with one and easy to assume there shouldn't be one.
 

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