Thanks I will email him again

Hello Everyone I bought a secondhand ride on lawn mower on 24th March this year, it was from a dealer and was advertised online, but I can't remember which site. It cost £3200 I paid by bacs, because of the drought I have only used it for 5 hours (by the mower hour clock) so far, last night it dumped the transmission oil out and lost all drive, it looks like it has been repaired and bodged up as I can see instant gasket sealant hanging out. Without getting a mechanics opinion I would think that it needs a new hydrostatic transmission. Do I have any rights under the sale of goods etc etc. It is a domestic machine and I bought it to cut my own lawns not as a business. I have contacted the seller, his reply was more or less "tough luck, not my problem" . I did quote this: Under the Consumer Rights Act 2015, goods should be of a satisfactory quality, fit for purpose and as described. My rights have been breached because the item you sold me is faulty. I would like a refund/repair/replacement." He replied that as it was a secondhand vehicle I only had 30 days to complain. Do I have any right to a refund? I have looked at the Consumer Rights Act 2015 but it's in legalese, I think I might have grounds to send it back as it's within 6 months but I can't find a specific reference so that I can metaphorically use it to beat the seller over the head with.