Stihl brushcutter. New head - not tapped...?

[Jimbo]

Hi folks,

I have a Stihl FS-55C brushcutter that ended up with a banana-shaped conrod. On disassembly I noticed some light scoring of the barrel so to be safe I ordered a new barrel and piston (part no. 4140 020 1203) along with the new conrod.
I'm starting to put everything back together and notice that the barrel has none of the bolt holes tapped. So that's inlet and outlet ports, crank-case bolts, and the spark generator mounting holes.
The bolts that came off the old barrel seem like they might be self-tappers, but I'm not sure. Can anybody advise?

Cheers
J

 

[Burnerman]

Stihl are using self tapping screws frequently these days, and this does seem to prevent them slackening off.
You must, however, use the genuine Stihl screw which is suitably strong and sharp.
They are about a quid each though!
John