Does anyone know the approx cost of cylinder head parts and fitting?
My garage says that as a spark plug is hellicoiled in on my car that there is little compression (poor starting), and the only way to solve it is a new head.

<cough>ollocks.

There's a lot of cars going around with helicoiled plugs quite happily. All a helicoil is is a replacement for the stripped original plug thread. If the plug stays in, and there's no blow-by up the thread (and you'd know about it!), then the helicoil can have no effect on compression.

I think your garage are telling you that they don't have much of a clue, they don't think you have much of a clue, but they like your money.

The only correct response you can give them to that is "That's a coincidence. I like my money, too - and I'll be seeing considerably more of it than you will in the future..."

Hummm, yes. He is a 2CV friendly garage, but I do think he likes to be a bit too thourgh and use a lot of new parts. Originally the plug was glued in aswell, but he said he doesn't like a bodge so it is now in without glue.

I'm with him on that one...

helicoil should be stronger than the original thread, threaded holes in alloy that need regular dismantling is what the things were invented for

a decent 2nd hand head should be quite cheap...beer token cheap
a pair of new ones can be had for £150 http://www.ecas2cvparts.co.uk/cylinder-heads-2cv6-pair-leadfree-fuel-valves-included-notes-p-1686.html

youll need valves but still a bargain

Sean

Can we just clarify what we're talking about here, this is a Helicoil, and is a piece of square wire wound into a spiral. I personally would try very hard not to have to use one on something I was expecting to dismantle again.


This thing is often called a 'timesert', and is, IMHO, considerably superior and a suitable permanent repair for things like spark plug and sump drain threads.

yup,

used extensivley in aerospace to provide a strong thread in lightweight alloy keeps Boeing747s and Spaceshuttles together
http://www.emhart.com/products/helicoil.asp
should be ok in a Citroen if done right

Really, I'm amazed. I don't like 'em. Perhaps they work better if 'done right' to aircraft standards, but I've come across enough that won't stay put to put me off. Bearing in mind that they've frequently being used, and sometimes put in, by the same cack-handed bodger that stripped the thread in the first place, they're not exactly fool proof.
http://www.timesert.com/

yes and repeatedly abused before somone gets the car off them to save it

Wurth are good but ive seen them unwind too the set up cost is pretty steep for the DIY/home mechanic, very similar to the "case savers" used on the magnesium alloy aircooled VW blocks

Sean