Thread the head

[w31mrk]

Hi,
I have just removed my sparkplug from my 899cc Cinquecento, as the car was starting very lazily when it was cold. Haynes manual suggested to check the gap in the spark plugs.
When i removed the 1st spark plug, it appears that the thread in the head has come out with it, I just thought it was some gunk in the plug.
I cleaned it out, cleaned and regapped the plug and it now won't go back in as there is no thread in the head.
What can I do??
Helicoil - costings if any idea?
New head - Costings?
I wont be able to do this myself as I am not that mechanically minded, so costings are important.

 

[s130]

You may be lucky in that there is some thread left in the head and it just needs chasing through with a thread reair tool or thread cutter.

This is you can do yourself if you have the right tools, or you can get a local machine shop to do it for you. There is no nead for the head to be removed as long as access is good enough to get a tap and die in there.

If the thread is totally gone then as you say either a new head or a helicoil. Fitting a helicoil with the head insitue is a rather delicate job. You have to get the swarf back out of the cyling and more difficult is breaking off the tang and retrieving it to the outside world.

Aluminium swarf the cylinder/engine can cope with but a helicoil tang is rock hard and will rapidly damage the cylinder bores/block.

If going the helicoil route then it is best to remove the head.