Gc1710 mow deck / 3PH adjust linkage

[Rgwitt]

Hi all, new here looking for help. 60” MMM dive over. When I lose the deck the right side goes down about an inch or more before the left side moves . I tried adjusting the link and it changes somewhat but not enough. The manual says adjust upper link and under link. I can only find one adjustment at the lift bar. The diagram in the manual is too small and unusable. Looking for advice on how to adjust.
Thank you

 

[Dmacleo]

if the ends of the lift shaft (shaft goes side to side in frame and is PAIN to replace and runs around 180$) are even then no worries. rt side of deck is little heavier and as it starts to lower left side tilts up a touch on the slots in lift linkage.
plus on GC2400 the actual lift linkage is on left side running from the lift assy of rear 3ph to the mid mount lift shaft. not sure if 1710 same.
I had a bent lift shaft, rt side of shaft was noticeable degrees different then left side. with deck fully up rt side sat inches lower than left. so replace the arm. a real pain.
now right side lowers first, left side lifts first but at most only 1 inch difference. as right side wheels hit ground left side wheels 1 inch high. I prob could adjust the lift connectors to even it out but no real need, gauge wheels follow terrain as needed and deck is level when on wheels.

yeah 1710 is similar

 

[Rgwitt]

Thank you. It looks like the lift shaft has some play at the pins but is straight. Thought maybe that was the issue, but what you describe that your deck does after replacement I think I’m okay there. I looked at the shaft and can see the difficulty. I’ve got the TLB and the framework for that would need to come off. I was dreading that .

 

[coldsteelva]

I'm not sure of the geometry of yours specifically, but on my GC1720 with the 2326 60-inch drive over, I just replaced that threaded lift link after 7 years of use/abuse. From day one at delivery, approximately 1/3 of the threads were visible ABOVE the threaded hole. 1/3 in the thread engagement and 1/3 below. Try pulling the pin and threading the link in more.

 

[Rgwitt]

OK , thanks. Mine was situated the same 1/3 . I adjusted mine in about 1/2 of the threads . It made a positive change but didn’t get the deck get all that a need

 

[coldsteelva]

What position is your mower height dial in? If you have the dial in Position 1 (lowest/scalping) setting, then you should have nothing preventing the deck casters from reaching the floor. Just beyond the highest setting (5) is the LOCK setting which prevents movement of the mid-mount arms down when the 3PH is being used.

Remember that the 3PH and the mid-mount are connected via linkage as there is only a single source for hydraulic lift. It's possible that if you adjusted the threaded linkage with the dial above Position 1 that you aren't getting appropriate range.

And to get this out of the way: officially the 2326 Heavy Duty MMM height adjustment is supposed to be set only by the caster pin settings on the deck itself and you're not technically supposed to use the MMM suspension system on the tractor to maintain the height of the much heavier 60-inch drive over deck. Your supposed to just have the dial set to 1 and operate the 2326 with all weight on the casters and none on the suspension. I will admit that the GC series is pretty robust and I have been using the dial settings AND the caster settings for 7 years with only that single link failure. My ground is uneven so I let the tractor suspension system help me keep the mower deck from smashing into the face of rising ground/rocks/roots/etc. I have smashed and had to pry out the nose wheel when I wasn't using the dial and I drove my deck squarely into the immovable concrete lip of my garage. OOPS

 

[Rgwitt]

Thanks for the input. I have a full understanding of the height adjustment knob and am using it correctly . What’s happening is that I would like to use the adjuster to set my mow height , but due to the linkage issues ( and as you point out , the weight of the deck ) my deck lifts and lowers unevenly. I want to avoid using the wheels due to the lines they leave. One response mentioned the tractor lift arm may be bent as part of the problem.
What I’m piecing together here is the issue is a combination of elements.
1- the weight of the deck
2- the inherent play in the whole system
3- wear points
I think these combined cause the uneven raising and lowering of the deck and the best I can do if I want to use the height adjustment knob is to get it as close as I can and live with it. If I need to maintain a parallel cut I need to use the wheels.

 

[Rgwitt]

if the ends of the lift shaft (shaft goes side to side in frame and is PAIN to replace and runs around 180$) are even then no worries. rt side of deck is little heavier and as it starts to lower left side tilts up a touch on the slots in lift linkage.
plus on GC2400 the actual lift linkage is on left side running from the lift assy of rear 3ph to the mid mount lift shaft. not sure if 1710 same.
I had a bent lift shaft, rt side of shaft was noticeable degrees different then left side. with deck fully up rt side sat inches lower than left. so replace the arm. a real pain.
now right side lowers first, left side lifts first but at most only 1 inch difference. as right side wheels hit ground left side wheels 1 inch high. I prob could adjust the lift connectors to even it out but no real need, gauge wheels follow terrain as needed and deck is level when on wheels.

yeah 1710 is similar

View attachment 820043

By the way, can I ask where you got the parts explosion from?
I could not find one anywhere. Those are really helpful .
Thanks

 

[Dmacleo]

By the way, can I ask where you got the parts explosion from?
I could not find one anywhere. Those are really helpful .
Thanks

https://parts.agcocorp.com/us/en/

click search by parts book
can't link direct to book and paste here, have to start at the main page.
then I just took screenshot and posted that image.

 

[Rgwitt]

Thanks,
I did go to their website to try to find information. Frustrating to say the least. I’ll try again