Technical Fire distributor o-ring

[Pullu]

Hello everyone, i just read this guide on the distibutor o-ring https://www.fiatforum.com/uno-guides/43921-curing-distributor-oil-leak-fire-engine-uno.html and since mine is spitting out oil too i got interested in changing it. Can anyone tell me the diameter and thickness of the o-ring please ? Thanks

 

[firstcar-Y10]

http://www.ebay.co.uk/itm/330739553252?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

 

[Pullu]

forgot to update this thread but i managed to fit an o-ring with ID 36mm and OD 3.5mm and not a drop of oil came out since then