When he retires in February, at the age of 83, he will have put in 45 years of service at the Bridge Swimming Club.
His work has now been honoured by his award this week as a BBC 'Unsung Hero' - but he remains modesty itself.
"It's a pleasure passing on skills, whether swimming, badminton, cricket or football," he told BBC Sport.
"But really it was so gratifying just to be nominated. There are so many other people all very deserving of this award who have never even been nominated.
"And I have to thank the people at the Bridge Swimming Club, particularly Sue Robinson, who nominated me."
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It was a chance conversation with a friend on a school playground that led to Finney first becoming involved.
His own son became a member. That son is now 52 and, on account of ill health, Finney is to now move away from the area and be nearer to him.
But he will go into retirement having shaped the sporting future of so many youngsters, having taught pupils from the age of five to 16.
And his own involvement in the often thankless world of sports organisation goes back even further, to when he helped set up the Stonehouse Gang Youth Club in the Birmingham suburb of Selly Oak 70 years ago.
"As a child, I was so nervous, I wouldn't say boo to a goose," he told BBC Midlands Today. "I joined the Stonehouse Gang to play football at 13 and found my way in the gang
"I started playing table tennis there and, once I'd been trained, I wanted to pass on my skills. The same happened with badminton.
"To mark out the court, we started off by laying tape down in the school hall at Paganel Road School. But I ended up having to ask permission to paint the lines."
Truly, a man who, in more than one way has left his mark.
David Finney was still the right side of 40 when he helped launch a swimming club in the Worcestershire town of Redditch in 1972.