Overtightened spark plugs? 2012 3dr match 60 1.2

[jimboaty]

I replaced my spark plugs today on my 1.2 L Macth 60 (2012).

I was careful to hand tighten them and am sure I havnt cross threaded them as I did that 'turn anticlockwise until you feel the threads sit' technique before hand tightening. I dont have a torque wrench (I know, I know) so just used the guide of turning 1/2 - 2/3 of a turn after had tightening. It took the whole 2/3 of a turn, plus a bit more until it felt that there was no more resistance tightening with a 3/8 ratchet wrench.

I'm a little worried I've overtightened as I went that little bit past 2/3 of a turn until I could feel it 'stop'.

Took the car around the block and no issues. Its due to go to the garage for a pre-MOT and MOT in 2 days time, and wont be driven until then.

My plan was to get the garage to check the torque for me, for piece of mind. Its about 4 miles away though so wondering if the drive may damage the threads if they have actually been overtightened?
I could loosen them off and try tightening again to about 1/12 of a turn, like the NGK website suggests for 'reusing' spark plugs, but without a torque wrench I may still have the same issue.

Any thoughts on whether to just drive it to garage, or try loosening and re-tightening?

Thanks for your help.

[RUM4MO]

That engine has a steel cylinder head so I don't think that you will have done any damage, now I would not try that trick on an engine with an alloy head though.

Edit:- I should have said cast iron cylinder head not a steel cylinder head!

[spartacus68]

I'm sure it's fine. Good call to thread the spark plug with the socket by hand. I have a Tohatsu outboard with an alloy head that was stripped. Only repair was steel inserts. I wouldn't be using a torque wrench, basically nip them up and add a smidgen of torque, less than a quarter turn. Oh, and don't grease the threads.