confused 2 washers under head bolts

Just started to striping my engine to replace tubes and seals, found all the head bolts have two washers under each nut is this normal as can't remember seeing it like that last time I built and air cooled engine any idea's @zed or @Paul Weeding cheers

 

No but the washer should be really thick approx 2-3mm so maybe builder didn't have them. If you buy an engine case fittings kit you get rubbish thin ones and thin nuts.

 

Thanks zed, the washers are thick and thin so I will lose the thin one's wot you think?

 

And then you will possibly find the thick washers have 10 mm holes and the thin ones have 8mm holes.

 

Nope the thick ones are the proper washers but have thin one but both are 8mm hole ?