Assuming you have the 615-092-01-08 fuel filter head:
The hollow bolt takes a
18 x 22 x 1.5 mm aluminum sealing ring
sold by our forum sponsor
Don't forget to replace the o-ring as well.
On 11/17/2014, I sourced some Viton ones from Global O-Ring and Seal
(2.5 mm CS X 10 mm ID) and can part with some.
Send me a PM, if you would like a few.
The photo shows the hollow bolt on the left, new crush washer and Viton o-ring in the center and on the right the old deformed aluminum crush washer and old hardened broken o-ring
