Ford Focus - 12 years old, broke timing belt. The garage is saying I need a complete new cylinder head. I suspected it was the timing belt and expected several bent valves at worst. My question is simply "is there any way a broken timing belt could possibly result in damage requiring the cylinder head replacement"

If it is an interference type engine valves might be damaged along with piston heads. If a 4 cylinder not an interference type but new belt requires mechanical timing when replaced.

I put your question into internet explorer & apparently
there are 2 engines in 2001 & 2001 that are interference

Seen the 2002 are the way to go if your buying one.

You can do a cylinder leak down test & there are some
nice cameras that go into small places that are for checking
things even inside your head thru the spark plug hole

Your not going to buy any of that,but can have those services
performed for piece of mind

A compression test is not really giving you the whole picture
that a cylinder leak down test would

Play around on You Tube & learn all you can

You need to be certain that the intake manifold is completely free of parts/remnants of the "old" valve seat that shattered. If you do not clean and blow out the intake manifold with compressed air before installing in on the new head, chunks of the old seat can and likely will find their way back into the combustion chamber.

well this is what you have to do send the cylinder head to a machine shop for any internal damage check any bend valve install a new water pump new timing belt and problem solve

You would be very lucky to get away without any damage. For the moment, get a timing belt, line up the timing marks, put the belt on and adjust it as per the manual. Turn the engine by hand, or using the pulley bolt. If after two turns of th engine, that is a complete 360 and nothing stops or locks up then you may not have any damage at all. Try and start the car.

The most likely damage would be, bent valves, broken or burst pistons, valve pushed through the cylinder head, in other words a shot engine. This is the worst case scenario, but it is most likely that one of the above will have happened, in which case the engine will not turn through 360, you should then proceed to take off the cylinder head and check for damage.

In the good old days, you could have a timing belt break without any damage, not now though, particularly with 16vs. although damage also occurs with 8 and 12 vavle engines.

Sounds like a zetec 16v that is the most common engine in the year focus. they are like poeple say a "safe engine" they tend not to damage the valves when the belt go's although there is still a possibility.

If you where sat at the lights then you should be ok.

Hope this was helpful

Regards
Dan

take it to a garage because the valves will have hit the pistons requiring a complete head off job and new valves and maybe even a piston or two ,1990 ,its an old banger and petrol so its worth at most a 1000euros in good running order with a years roadworthy certificate .Dump it

it sounds like the head gasket is blown, unfortunately head could also be warped. and yes a garage is going to cost quite a bit

My dad had this problem for years. He always cleared it out when the engine misfired. Ford did not want to know. Garages did not want to look.
Eventually i found someone who had seen it before.
Along side each pair of plugs there is a 'core plug' sitting at the bottom (some Focus's have a sort of big grub screw instead). These get pourous or holed letting coolant out.
It is hard to see these things as they will be under a layer of 'silt'.
New core plus fitted and job done. No problem for 6 months now.

cheapest option complete head strip, should be able to order new valves, just hope you havent cracked or put a hole in a piston, easiest (and most reliable) option complete recon head (not cheap)but is guaranteed to be perfect. id say as for only 40 000, if you have reciepts, and it wasnt too long ago it was done you may have warantie comback and itll all be done for free.