2005 GX255 - Mower Height and other Qs (54C deck)

[creekscout]

On the left side there is a 3/8 space and on the right side 1/8 space between what I would call the bumpstops. I don't know how to post pictures or I would show you.

 

[dadohead]

Been thinking about it.... the new C mower decks came in with the GX tractors too if I'm not mistaken. Big upgrade.

Ok, your tractor probably took a large impact to the LH wheel and was bent back. To test that the RH side is not bent, turn the steering wheel to the right with tractor stationary (steering cylinder will retract) and see if the 1/8" gap on the rh side closes up. If it does then the LH side of the axle is only place it is bent. The LH gap will probably increase to 1/2". Remove the axle and lay a straight edge over the axle pads and center pivot boss. They SHOULD be coplaner. Yours probably won't be (by 1/2" guessing). Several repair choices:

• Could replace the axle (find a used one)
• Could take to a shop and have it bent back (ductile iron will allow this)
• Could braze on an extension on the LH pad to make coplaner
• Could drill and tap a hole in the LH pad and assemble a bolt making it coplaner over the bolt head

Probably other options. Whichever you choose, replace the pivot bushings. Let us know your progress. Hope this helps!

 

[creekscout]

Great information, I will let you know the results. Thank you

 

[smp22]

Hi smp22,
Your GX uses an Achermann style steering system. LH/RH spindle coordination is controlled by a straight tie rod. The system is turned by a frame mounted cylinder pushing the steering arm forward/rearward (#23).

View attachment 880673
So just normal steering imparts the same fwd/rev force into the axle pivot. The axle has outrigger pads on the front side that rub against the frame saddle supporting this action. From your description, the axle pivot has become worn/sloppy allowing front/back twisting movement. As the axle 'floats' it is not responsive to your steering inputs. Result: you can't keep it steering straight!

Test: with the tractor running and park brake ON. Have someone turn the steering wheel left then right. Observe the front axle on the left side of the machine. Do you see the axle move forward/backward much before seeing the front wheels turn? If so, this is the problem.

As mentioned above, the steering is pretty robust and this usually doesn't happen on low hour machines like yours. There is one circumstance that causes it though: a bent axle. It can happen when the steering is at full lock (when it is most vulnerable) and the front wheel strikes something hard. The axle is nodular iron; it can be bent! If this happens, the support pad (on either side of the machine) is bent away from the frame saddle... it now has no outrigger support and wear is accelerated. Inspect both axle support pads and see if it is contacting the frame saddle. If there is a gap, the axle is bent back. Report back and we can offer direction to get you going. Lots to digest here... sorry.

We've been on our summer family vacation and just got back. All I managed to do was cut some grass and take this video, where you can see that what you suggested appears to be the situation. A replacement axle sounds expensive, if even available. Can that gap be filled and would that "solve" things? Thanks much for the guidance and advise thus far.

 

[dadohead]

Ah!... the video helped!

I remember now (it's been 20 years). The GX255 uses a GT steering axle and applies steering assist... not full power steering. Here is the correct breakdown of your steering (still an Ackermann system driven by drag link "H" though):

So, NO front support pads. The wear parts are the axle center pivot bushings (D). Also check the sector gear (P) for sloppiness. In extreme cases, the teeth will be worn in the center region allowing the tractor to 'wonder' as you go straight.

Let us know what you find. If you dive in, I can post exerts from my TM with pics/torques etc. Hope this helps!