FV430 track adjuster idler arm tension

[andym]

I've just posted this to the Tapatalk FV430 group, but think it bears repetition.

I think that most of us have had fun with stuck track adjuster idler arms, probably because the adjusters don't get enough use in civilian life.  I still recommend that once a year you should remove the drain bolt from the adjuster and slowly drive the vehicle forward to allow the idler arm to move fully forward, then replace the bolt and re-tension the track.

However, I recently came across an eBay seller offering a copy of EMER (Trk) E107, the FV430 Modification Instructions and as I hadn't seen that before, I bought it. 

Mod Instr No.1 is very interesting - "Increased clearance for track adjusters".  It says that to ensure free movement of the idler arm, the clearance between arm and cap is to be increased by removing shims and backing off the nut.  I don't think I've ever seen any shims between the arm and cap, but if you have any, discard them.  The really interesting thing is the next bit:

(d). Refit the pivot shaft end cap and sealing ring.
(e). Refit the castellated nut on pivot shaft so that it is screwed fully home but finger tight.
(f). Slacken the castellated nut between 2 and 3 flats (depending on the alignment of split pin hole to castellations.
(g). Lock castellated nut in position, using a new split pin.

I don't think I've ever seen this mentioned elsewhere, so it means that the castellated nuts on my vehicles are too tight, as are probably everyone else's.

Andy

[robin craig]

Andy,

 

this would allow the adjuster to have side to side movement would it? is that the intent? Or am I missing something?

[andym]

1 hour ago, robin craig said:

Andy,

 

this would allow the adjuster to have side to side movement would it? is that the intent? Or am I missing something?

That's precisely the intent Robin, to increase the end float from 0.005" to 0.025" according to the text.

Andy