JOHN Lawton, engineer, financial consultant, qualified chef, private investigator, former pub landlord, tarot card consultant and landscape and seascape artist, prefers to exhibit under the name of Coolbox.

"Coolbox is something I regard as a personality, not disorder," he likes to say more than once as he guides What's On around York, Countryside and Coast, his debut Grays Court show in York.

"It's easy to separate the two. You're interviewing John but you're also interviewing Coolbox, who allows me to be colourful and gives me freedom to paint something that's not 'draughtsmanly' perfect or in straight lines, whereas engineering work has to be so precise.

"By contrast, you look at one of my paintings once and it's like an injection of colour. The way I paint, it's so simple, it what I call 'caffeine painting'."

The Coolbox sobriquet has prosaic, if endearing, origins.

"I was doing 12-hour shifts as an engineer in Hull, doing stuff for British Aerospace, and as there were two Johns on my shift, whenever you sign in or off, I would put John (Coolbox) and became known as JCB, which has been my name in the engineering trade for a long time," says John, a splendidly artistic vision in luxuriant pointy beard beard and pinstripe waistcoat.

"So I thought I'd acknowledge my 30 years in engineering by bringing that side of my personality into my art, and that's why I'm now signing my work as Coolbox," he says.

Should you be wondering why he called himself that name in his 9 to 5 engineering life, let John explain. "I used to bring a big cool box to work with my sandwiches and drinks for when I was on a long shift," he says.

For some years now, Coolbox has been painting the East Riding and Yorkshire coastal scenery, bumping into David Hockney on the Wolds lanes on occasions, and holding private exhibitions in guest houses, hotels and homes of business friends or acquaintances around the coast.

Now he is in his "third age", aged somewhere unspecific over 60, he focuses on his painting and driftwood art in his Nafferton studio, but in earlier days he made iron sculptures when working in the engineering industry in the 1970s.

It is all part of a polymath's life that has taken in running the Royal Oak pub in Driffield for 14 years, being a tarot-reading consultant for problem-solving phoneline psychics – "ten of swords is the best card," he says – and studying multiple courses, including a diploma in counselling and psychotherapy.

Yet everything ground to a halt in 2004.

"I lost 3½ stone in 17 days from pleurisy, pericarditis and viral pneumonia. I very nearly died," he says. "I was getting to the point of death. Everything I saw was orange – and the colour of death is orange, as Mexicans believe - and I was in the here and now, the point where I could live or die, and I chose to live."

Why: "I thought it was a good idea...because I enjoy being alive," he says, with a twinkle in the eye behind the tortoiseshell spectacles.

"Since that situation, I decided I would do whatever I want, not for the value of money but for the pleasure of working, and that's when I started painting seriously, though I still run my financial consultancy business, part-time, and I'm a private investigator as a member of the Association of British Investigators and Process Services. That was the most difficult thing I ever had to get into in my life. Acquiring a firearms certificate is a lot easier."

After changing careers "three or four times", John is enjoying focusing on art and family. "Now I'm financially independent, I can pursue something I don't need to make a living out of," he says.

"Being an artist is easy;you get up and paint or sculpt all day, then sell your work...or I wish it was as easy as that! Painting is frustrating, time consuming, energy draining, mind messing! Did I mention frustrating? Having to organise, promote and publicise your work on top of that is very difficult."

This brief lull into the downside of the artist's daily diary soon makes way for another injection of Coolbox coloratura. "The joy of being an artist is to be able to express yourself , exorcise your creative urges. It's addictive and all pervasive," he says. "Mmm, I meant 'exercise' but I think 'exorcise' works well as it is."

For his paintings and sculpture, Coolbox will take photographs and collect driftwood in the summer, heading out on his Triumph Tiger 1050 motorbike or in his Citroen Berlingo van with his wife and gundog, and he will then concentrate on painting in his Nafferton sun lounge most days in the winter, bringing colour to the drabness of that season.

"The reason why I paint in bold colours is because I distil what I see and make it as strong as possible. I've always looked at a tree and let it tell me what colour it should be painted," he says.

"Don't forget; I'm a tarot reader, where you work with imagery and interpret it. I might start with the perfect sketch, but then I'll distort the buildings, as I paint my own perception of it, rather than a photographic iange."

You will never have seen York Minster or Staithes in the "wonky" Coolbox style before and yet they remain entirely recognisable.

John "Coolbox" Lawton's spring exhibition, York, Countryside and Coast, is running at Grays Court, Chapter House Street, York, until the end of June. Admission is free; original artwork is for sale.