Ventrac Center Pivot

[mitchash]

We have two Ventrac 4500Zs, they have been great machines. But both have the center pivot loose. Anyone know the procedure of replacing them?
Thanks

 

[MountainBuck]

How many hours are on them? Were they greased regularly?

 

[mitchash]

They are machines at my work and probably didn’t get greased as much as they should. I would have to look but I think the one has close to 2000 hours.

 

[mitchash]

I looked at the hours, one has 500 and the other has 1000 hours.

 

[johara1]

Look at the parts manual ..... I would look at the bar on the bottom first and check for play on both ends.... jim

 

[TOYBARN]

I have replaced both the lower bar and the upper center pivot assembly on my 4500Z Ventrac. Dealer told me it was difficult to change the upper and to drop it off to have them do the repair. I changed the upper out in less time than loading it up and traveling 40 miles to drop it off at dealer. The retaining nut on the center pivot will require some heat to release the nut. Tight fit but it will come off. My ventrac started bucking front to back when running the aero-vator last fall and I had to reduce speed to continue through that day. Replaced upper and problem went away. I had about 650 hours on the unit at that time.

 

[johara1]

I'm just starting to see some play in mine at 600 hrs. but you have to look for it. Mine is well greased too.... jim

 

[ShadyHill]

How expensive of a repair is this? I need to keep this in mind during my search for a machine.

 

[johara1]

I have no idea, but keep it greased and you should never find out..... jim

 

[johara1]

I have replaced both the lower bar and the upper center pivot assembly on my 4500Z Ventrac. Dealer told me it was difficult to change the upper and to drop it off to have them do the repair. I changed the upper out in less time than loading it up and traveling 40 miles to drop it off at dealer. The retaining nut on the center pivot will require some heat to release the nut. Tight fit but it will come off. My ventrac started bucking front to back when running the aero-vator last fall and I had to reduce speed to continue through that day. Replaced upper and problem went away. I had about 650 hours on the unit at that time.

The newer bottom bar has grease fittings on the ends..... jim

 

[TOYBARN]

One new upper center pivot assy is about $100. Labor not included. The part amounts to a 3 point hitch ball end welded to a mounting plate. Grease fittings are on both the upper center pivot and both ends of the dogbone bottom bar. Majority of the hours on my unit are from using an aera-vator with the seedbox attachment.

 

[johara1]

the older ones didn't have fittings..... jim

 

[prs]

Mine has always been well greased, but the fore/aft play has been there for a year or two and getting some worse. It has about 700 hours. By virtue of the difficulty in even getting a wrench onto those nts, it seems to be a difficult repair. Myabe Toybarn can share some pointers or something obvuious I have missed.

prs

 

[johara1]

is the play in the top or the bar at the bottom, or both...... jim

 

[prs]

Jim, I am thinking the play is in both; but I am a one man show here and I can not watch the dog bone or center pivot while grasping the roll bar and forcing the rocking motion. Next time my son visits I will seek his assistance while I observe. These joints take a lot of pressure during work and I think a high moly percentage grease would be better and typical multi-purpose types -- the stuff used on loader pins should be good. But, once worn, they will wear more regardless the grease formulae.

Do you see a good way to get a wrench or impact socket on them? The service chart give a spec for checking the torque, but I have not since I see no way to get on them. The OP of this thread says he had to use heat to loosen, are they thread locked?

prs

 

[johara1]

Jim, I am thinking the play is in both; but I am a one man show here and I can not watch the dog bone or center pivot while grasping the roll bar and forcing the rocking motion. Next time my son visits I will seek his assistance while I observe. These joints take a lot of pressure during work and I think a high moly percentage grease would be better and typical multi-purpose types -- the stuff used on loader pins should be good. But, once worn, they will wear more regardless the grease formulae.

Do you see a good way to get a wrench or impact socket on them? The service chart give a spec for checking the torque, but I have not since I see no way to get on them. The OP of this thread says he had to use heat to loosen, are they thread locked?

prs

Same here I'm on my own, top one is easier to see just remove the plate under the steering wheel near the bottom and where you can see the top bearing that has the large nut, then raise and lower the mower deck a little and see if there is any movement, if not, it's in the bottom bar...... jim

 

[prs]

Thanks. I should have figured that out after Toybarn mentioned the mounting plate thing.

prs

 

[mitchash]

Anyone know what the torque is on the top pivot point and dogbone bolts? Thanks

 

[prs]

150 foot pounds. The owner's manual is downloadable and has that spec. If you do this check, take photos of how you gained access with the wrench.

prs