Changing MMM Lift Shaft 2010 GC2400

[Dmacleo]

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1:first of all remove the long arm from frame to adjust link both sides, then remove adjust links.

2: remove the pin bolts on both ends of the lift shaft to allow pulling the lift link off. on Left side you will have to pull the 3pt lift arm I just pulled the 2 nuts on end (measured thread distance first for install reference) and loosened the link that way, when lift link off can just rotate and slide off.
Here's where the fun starts. if both will pull off (may have to put vise grips on shaft to hold) them rock link back and forth with hammer if needed. do NOT hammer against the wide portions (eg from under tractor to outside of tractor) as the link WILL bend. if they both come off...GREAT. course my left side stuck on. tried heating with torch, no good, just as my diff lock cable started to burn I ran out of acetylene. Just as well I guess.
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At that point its sawzall and metal cutting blades. its a *****. have to do a sideways cut from back end towards front and watch for fan interference. A 20V Max dewalt would not handle it, battery overheat. used 7amp corded. broke 5 blades, you will only be using 1 3/4 in of tip of blade with tip 1/8" out at worst point.
but anyways got that off and that side out, took to local garage put the stub end of shaft in vise heated the lift arm and spun it off.
then just remove the bronze bushings on each end.

3: ok that's out of the way. next up pull one bolt on rt side of tractor underneath holding the valve body in place. then pull the 1 bolt to that bracket (most stuff is 12mm thru this) under the floor mat going down. then pull the top bolt on hose end bracket where FEL connections are. this allows moving valve body down and inch and back about 2 inches this allows lift shaft to protrude enough w/o binding on the hyd lines to valve body.

4: pull the frame cross shaft in front of fan, 2 19mm bolts each end. use vise grips on rt side to prevent spinning while remove bolts. I used rt side as it prevented anything from hitting fan. also disconnect any wire looks there and one right where cables come down from engine area. this allows you to above that cross bar fwd about 3 inches and move the lines near fan down a bit to allow the lift limit pawl to clear fan and lines.

5: pull the limit adjust threaded rod out, there is cotter pin below the insert that sits in the shaft pawl.

6: pull front driveshaft (4wd) off rear, I used a wedge inside the split to widen then pry bar to pry off splines.

7: pull shaft out. insert new one. when inserting the limiter needs to face slightly fwd then once past fan rotated back a bit.

8: put everything back together making sure to tie the cables/etc back where fan wont interfere.

I am at step 8 now taking break, figured would post this while fresh in my mind.
cutting that one side took me better part of 3 hours due to blade damage/etc.
Have fun

 

[Dmacleo]

addendum: do yourself a HUGE favor.
sand the paint off the ends of new shaft BEFORE you put it in place and use a brake hone on the old lift arm links.
doing this before install will save you the ton of hassle I am dealing with now.

 

[Dmacleo]

thats a lot better. now all 4 casters touch down evenly, raise lifts both sides at same time (turnbuckles all the way up now) and arms both sit same distance from frame when up. rt side does carry little lower (approx 3/4") when all way up due to extra weight/length that side. but thats better than 1 3/4" difference left to right.

 

[kenmbz]

Thanks , this will be good reference material for others.

 

[hube2]

This is for my own future reference - should I have the problem and find this thread in the future.

Why you were changing this - What have you done with/to your GC Series 2300, 2400, 1700 Tractor TODAY

 

[Dmacleo]

This is for my own future reference - should I have the problem and find this thread in the future.

Why you were changing this - What have you done with/to your GC Series 2300, 2400, 1700 Tractor TODAY

with both turnbuckles set as high as possible end of lift rod (where it hooks to mower pins) set almost 1 3/4 inch lower than left side. when looking across ar pins that hold lift arms to lift shaft you can tell shaft was twisted.
no damage underneath so I don't think something bound up under causing the twist, I think just over time with the heavier right side sticking out further just wore it.
now my arms sit exactly the same, may drop left side 1/4 to 1/2" (using the adjustment) just to compensate for the heavier right side and make sure it always lowers/lifts exactly even. did notice right side casters (esp when front is rotated back) leaves the left front about 1/4" off ground.
thats a 2 minute job.

 

[hube2]

While I don't know for sure, riding an uneven surface my also twist it. The deck, like the 3PH floats down, upward pressure pushes the lift up. If you are running on the guide wheels and you get a lot more upward pressure on one side than the other, I think this could also cause that rod to twist.

On the other hand, in another 10 years I might be in no condition to be doing anything about it. I have a hard time crawling under my tractor to grease and change the oil as it is. But if I'm able I'd prefer to do it myself if I can.

 

[Dmacleo]

While I don't know for sure, riding an uneven surface my also twist it. The deck, like the 3PH floats down, upward pressure pushes the lift up. If you are running on the guide wheels and you get a lot more upward pressure on one side than the other, I think this could also cause that rod to twist.

On the other hand, in another 10 years I might be in no condition to be doing anything about it. I have a hard time crawling under my tractor to grease and change the oil as it is. But if I'm able I'd prefer to do it myself if I can.

I had thought about that, but the elongated slot hole on turnbuckle end allows quite a bit of up/down movement for each side.
plus the left side matched left side of new, the right side pin hole was quite a bit off.
meaning something forced DOWNWARDS on that right side.
I immediately thought a rock or something had gotten onto deck and hyd was strong enough during lift to twist rod, but there is zero evidence under tractor of it binding and the bushing was in great shape.

hell, I technically am in bad enough shape (thats a post for another time, I'll just say I got many VA drs who will call me after hours or on weekends) that I should not have done this.
just cannot afford to pay anyone to do it.

 

[hube2]

Don't mind me, I think a lot. Not saying you did anything wrong or did not do anything that I would not do. But I was thinking of things that could cause that shaft to twist.

If you use the deck locking knob to lock the deck all the way up for some reason, like you're using an implement on the 3PT and don't want the deck going up and down. Even without using the 3PH the hydraulics will eventually bleed down. Some people also mow without running on the guide wheels, depending on the height control knob for mower height. Any of these things would put all the weight of the deck on the locking mechanism on the left side of that shaft.

Now imagine bouncing though a field with the weight of the deck on that single point.

 

[Dmacleo]

nah you're thinking was right on .
and was first thing I looked towards,
key is when deck off, on a surface where your arms will be at same height, measure there.
if off by as much as mine was, shaft twisted.
deck up on NEW/GOOD shaft will always have rt side lower than left due to weight on rt side being more and the built in "slop" of the lift links allowing weight on rt to offset weight on left.
I verified this yesterday, lift links at same (w/i 1/8") height no deck on same surface (left to right) yet with deck on rt side sits little lower.
you can see the rt side sits heavy on the link elongated holes while the left side will easily sit close to middle of that hole.
thats all fine, simple adjust levels it.
problem for me was the OLD shaft had the whole arm sitting off a lot. I had to adjust my left side down TON to get a level lift/lower/sit etc