MC_BLADE

[QUOTE=m1bjr,Feb 15 2008, 03:09 PM]

Hunt about for a GOOD machine shop.
You can fill the head with something (like shaving gel) with the piston at BDC.
Make the insert (one piece sleeve like type best as no tang to snap off) and simply rotate the engine over TDC to expell the swarf. As mentioned, alloy is not too big a deal - recovering a tang end of a traditional helicoil is.

If done properly and bonded in you should get away with it for years and ought to cost less than

C&S Evo7

Ta good point, removed and Pm'd

eho

is the helicoil insert a more permanent / worry free solution?

MC_BLADE

Given the fact that you know how well your engine has been looked after, compared to a second hand engine which has no history I'd say yes. If you look after it and are careful when you change the plugs in the future you wont have to worry about it again.

If it does go wrong in 3-4 years time you will have more than got your 100 notes worth.

Edit: and given that Platinum plugs lasts 70k plus I doubt you will be changing them too often so I doubt you will have further problems

C&S Evo7

Helicoil is not a solution at all for this application. it is also possible the thread in the head is too far damaged for the helicoil to work.

a solid insert should be used, it would be a one time permanent fix, they are designed for this application exactly a helicoil is a general thread repair solution

MC_BLADE

I'd read that as helicoil/insert as both are different things, and either in theroy could work as opossed to replacing he block.

I agree though an insert will be the better option

m1bjr

Like said, depends upon how much meat is left in the old hole really.
Trouble with helicoils is they can pick up, especially with something like plugs that heat cycle and get mucky over time. Agree that if you can engineer it, a proper sleeve insert is a better option.

Worst case it's head off, but I wouldnt go swapping any parts out for exactly the reasons above.
Quite possible to do 'in situ' with a long enough tool

eho

i need the head off reguardless, i think it was the spark plug oil gasket that causes this in the first place. the head off option also gives a better repair, (helicoil / solid insert not decided, i talk to the mechanic when the head is out).

while i have the head off im thinking might as well spend a little extra and get it polished.

as regards to the bonnet repair, still awaiting for quote. again if it is too expensive, thinking of spend a little extra and get it carbon. i think i can pick up a carbon for

MC_BLADE

[QUOTE=eho,Feb 16 2008, 12:01 PM] i need the head off reguardless, i think it was the spark plug oil gasket that causes this in the first place.

Mans Best

this is a pretty relevant question = does anyone know the answer before we all start getting hysterical?!!