Another 5xi front axle repair

[Damien Walker 246]

Hi everybody, I have recently been very lucky to acquire a 520LXI which appears to be in very good condition ...... except for the steering which has various problems including loose track rod ends and the infamously weak front axle pivot. Given that this machine has only done 250hrs, it really does highlight the weakness in the design.

 

I found Snowmobileaddict's and Pullstart's repair threads (both excellent solutions might I add): 

 

but decided on a slightly different solution:

 

As both discuss, the weakness lies in Toro's reliance on a thread to withstand the sideloads....and what happens is that the thread wears down very rapidly at the same time as the hole in the 1/4" chassis plate wears oval. They should have used a plain shank bolt in a thicker chassis plate and simply used the thread to clamp it. But isn't hindsight a wonderful thing?

 

In my case, the wear wasn't too bad but it was exacerbated by the two pin-plate mounting bolts and the big nut on the pin all being loose. Never-the-less, it was there.

 

As imperial bolts are not that easy to obtain here (do-able but might take a while at considerable expense (and today is Sunday!), I decided against Snowmobileaddict's solution. Additionally, I DO have a welder and decided to beef up the front plate thickness (Pullstart's method) .

 

To retain the 'clamp down onto a shoulder' method of the original Toro pin, the 5/8" thread should have a plain shank to take the side loads. That would have meant making a new pin which I had already decided against, but it means that none of these three solutions actually clamp the front end of the pin à la original. All will tend to squeeze the two chassis plates together. I'm sure however, that all are significantly better than the original system, so may be this won't matter? (Ask me in another 250hrs!)

 

So, my solution adds a small threaded sleeve onto the 5/8" thread of the pin, just to extend the plain shank through the front chassis plate and into a welded on bush. The original large nut is retained too.

All initiaĺy went well: I turned the weld on bush (round not square in my case - easier lathe work!), I opened the hole in the front chassis plate with a step drill (actually to 22mm which is almost 7/8" - this means the extended plain shank WILL go through the axle!) and started on the threaded sleeve....turned to length, outside diameter (22mm) and then discovered I didn't have an internal threading tool small enough to to cut the thread! I also didn't have a 5/8" x 11 tap (I have 3/4" and 1" but NOT 5/8"!)

 

After considerable muttering and routing about, I found an old 5/8" machine tool t-slot bolt and stole the nut from it (I don't have a lathe or milling machine that huge) and turned that down to 22mm O.D.

 

It was then just a matter of reassembling it all and welding the bush on. I used Loctite type studloc to glue the threaded sleeve in position (easily removed later if required using a blowlamp). All done without removing the axle.

 

Eh voila! Much tighter steering and the tractor doesn't wander about alarmingly any more.

 

[Pullstart 62,653]

Well done, and congrats on the LXi!  If you weren’t aware, the “at” sign will tag a screen name @Damien Walker 

[Damien Walker 246]

8 hours ago, Pullstart said:

Well done, and congrats on the LXi!  If you weren’t aware, the “at” sign will tag a screen name @Damien Walker 

  Thanks for that, but where is the 'at' sign? I don't see one on my screen....

[Pullstart 62,653]

1 hour ago, Damien Walker said:

  Thanks for that, but where is the 'at' sign? I don't see one on my screen....

like an email address at sign.

[Damien Walker 246]

Ah! I was assuming it was a screen control that automatically pasted the link in. It seems that you have to type @ and the the members name? @Pullstart

 

Hmm, well that didn't work!...I'll keep practising!

 

@Pullstart - Aha!

 

Edited March 6, 2023 by Damien Walker

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