Thanks for your enquiry.
There are absolutely no immediate tax implications, if you were to take out a loan in your names and then give or loan that amount to your Son.
The only potential tax implication is that if you are gifting the sum to your Son, it would be seen as a lifetime gift, which means if you were to die within 7 years, the sum (or a percentage of it, depending on when you died) would still form part of your Estate when calculating if Inheritance Tax is payable. (As a couple, you have a tax free joint Estate of £650,000 for Inheritance tax purposes).
I hope this assists and sets out the legal position.
If I have helped, I would be grateful if you could rate my answer.
Thanks for your reply.
I can confirm that there are no tax implications of you doing what you propose.
I hope this clarifies the position.