Honda dealership not willing to repair head gasket failure under warranty - what should I do?

I've bought a second hand petrol Honda Civic 1.8 with 20,000 miles on the clock. I got it 10 months ago from a Honda dealership with a 1 year warranty. 3 months after the purchase, I experienced a radiator failure which caused the engine to overheat and cut out. Upon diagnosis Honda took liability for this failure and replaced the radiator. 6 months after this repair (approximately 6000 miles later), I experienced engine overheating again (this time I stopped the car and called the AA before the engine cut out). Turns out, I've blown my head gasket and warped my cylinder head. Upon diagnosis, Honda have offered 20 per cent compensation of total repair cost (which is large) and are not willing to budge from this offer. Contacting Honda UK Customer Relations, they refused to get involved with this case and suggested I raise further with the motor ombudsman. Do you have any advice?
I'm not very confident about the Motor Ombudsman. Seems to me that you bought a car with a fundamental fault and this fundamental fault was never completely fixed. I think you have a very strong case against the dealer who originally sold you the car that all of the problems you have had with it were present or developing on the date of sale. See:
Answered by Honest John on

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