I somehow sheared off my deck idler pulley arm bolt. On the diagram online, it shows 2 friction washers, 2 plain washers, and 2 more unlabeled washers on each side of the idler arm.

I found the friction washers and plain washers in the grass where my mower stopped. Any idea what the other washers are?

In the attached picture, I broke bolt 38, and have washers 12 and 13. No clue what the unlabeled things are.

Thanks for any help.

Posting a link for that pic as we don't know the model, year etc, would help...
 
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I suppose that would help. Toro Titan, number 76601.

https://www.partstree.com/models/76601-toro-60-titan-max-zero-turn-mower-sn-400000000-409103363/60in-deck-assembly-0/
 
Odd their not numbered... 
 
As #13 is a composite friction washer, I would suspect the adjacent washers are just flat washers
#13 would sandwich in.  
 
The key is to grease everything and make sure there isn't any binding to that idler arm. 
The bolt that holds it altogether isn't shouldered so your setting the drag when re-assembling.
 
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