This is exactly what you should. Give the company that did the work the opportunity to make right at their cost, or certainly make an assessment as to what the problem is. If they have fitted warped heads they are in the wrong and should know better. If you do not get anywhere with them I would consider the small claims court given the amount you paid and any additional cost you may incur to make it right. The consumer rights act changed in Oct last year and you'll be surprised how in favour they are for the customer.
Good luck

 

You cant prove they fitted warped heads.... All they have to do is say they checked the heads before fotted and they were fine.

Also the fact it has already over heated, so if they werent warped before they probably are now!

Youre not gonna get anywhere with the garage at all.

 

If the garage's poor workmanship caused the hg to fail and any other damage, such as the heads to warp, I think he has a case against them. For the money exchanged for the work, I would take it back.

 

He did not pay for the work, nor did he commission it.

Nor does he have any proof poor workmanship caused the failure...

 

Ahhh, scuppered

 

Yep, you are talking a good will gesture at best if you can scare them with some threatening letters etc. But as per most garages they know they are untouchable