Put it down to experience

Rick gets deep and meaningful on the subject of knowledge – all inspired by an oil pump

‘No sense getting older if you don’t get wiser.’ Well, I think I’ve cracked it. This Indian oil pump wasn’t pumping. It has a rotating drum with two spring-loaded plungers sticking out of the end. They draw in and expel oil from two ports in opposite sides of the barrel that pass the tank supply and the feed to the engine.

The plungers are operated by a ‘swash plate’ – a stationary disc slanted to act as a face cam. Pivoted, like an inn sign, a screw adjusts the angle of the disc to increase or reduce plunger travel and thus supply. If the disc were level, you’d get no oil – but it wasn’t and nothing was broken, so I couldn’t understand why on earth it wasn’t working.

Ah, but – like that inn sign – the disc can pivot both ways. An overlong adjuster screw that had been wound in too far, had pushed it ‘beyond zero’ – the high side was now the low side, so the pump was blowing instead of sucking as it passed the oil supply. Ha, simple. But the thing is, I found some notes I’d made about these pumps 20 years ago. Dear me! I’d got the adjustment bit right – but only by luck; I obviously hadn’t a clue how the pump really worked. But I wouldn’t say I’m a ‘better mechanic’ now than then, so what’s changed?

This was the first total-loss pump I encountered. I think I was too hung up on post-war high-delivery systems to get my head around it. Since then, I’ve worked on so many different 1920s bikes that I have a much wider understanding. Knowledge has depth and breadth. Depth makes the expert, but it’s breadth based on experience that will guide you through the unfamiliar – and that’s what you gain over the years.

‘BREADTH BASED ON EXPERIENCE WILL GUIDE YOU THROUGH THE UNFAMILIAR’

Sometimes ‘simple’ can be too simple to understand

WHO IS RICK? Rick Parkington has been riding and fixing classic bikes for decades. He lives and fettles in a fully tooled up shed in his back garden.