John Simister
John finds out why MOT exemption is a bad idea
When John’s modern lets him down, he worries for neglected classics.
We’re very broad-minded here at PC, so you’ll see lots of old cars in these pages whose claim to classicdom might not be as strong as the purists would like. Never mind; if it’s interesting, and it has a story to tell, we’ll write about it.
So, here’s a story about the Toyota Corolla Verso MPV that family Simister has run since it was new in late 2001. It gives a great view out, has surprisingly entertaining yet comfortable dynamics, and the dog loves it. Even better, it has suffered no rust in its bodywork and it never goes wrong.
Ah. Saying that, as I did during a recent holiday in Pembrokeshire, was not wise. As I manoeuvred the Toyota in a car park at Pwllgwaelod, the brake pedal went to the floor. I pumped the pedal and there was some resistance each time, but still the pedal sank. I hopped out and discovered a puddle of fluid just ahead of the offside rear wheel. Seems the steel brake pipe there, whose light corrosion was advised at the 2010 MOT but which has escaped comment since not least because it was regularly re-coated in rust-resisting wax, had finally let go.
Reason to be thankful
First thought: thank all deities that this didn’t happen during a sudden traffic-thrombosis stop on the M4 on the way west. Second thought: if this can happen to a relatively new, in PC terms, car, what are the chances of it happening to car now of Mot-exempt age that, as will surely happen despite everyone’s best intentions, may never again receive a critical look at its underbody? It’s another good reason why MOT exemption is a daft and dangerous idea – and it’s also a salutary reminder that covering a deteriorating brake pipe in wax isn’t necessarily going to stop further rot.
A friend gave me a lift to a nearby filling station where I bought a litre of brake fluid. Then, with reservoir refilled, I tentatively drove back to Newport, where we were staying, trusting in the handbrake and the non-leaking half of the dualcircuit braking system. The village has an excellent garage run by Robbie and Nathan, who spliced in a new piece of pipe with impressive efficiency.
They showed me the tiny hole in the old piece, and how most of the pipe is plastic-covered and has stayed in perfect condition. It’s just the tight bend at the end that isn’t covered. I was surprised the corrosion hadn’t been assessed these past eight years; they said that MOT testers aren’t allowed to scrape away protective coatings to check.
And now, another MOT tale. I took the Stiletto for the last test it has legally needed, although I’ll be continuing its annual check for obvious reasons.
As a 1968 car it’s exempt from emissions testing, but we checked the CO anyway as I was interested to see what it would be. Bear in mind here that I had carefully set the twin Strombergs’ mixture by ear until I got the smoothest idle. When you’ve been fiddling with carbs for years, you get an instinct for it. Or do you? The seven per cent CO reading suggested not. So, I dug out my Gunson Gastester to see exactly what was going on.
Sensitive work
It turns out that the Strombergs’ jet-height adjusters are far more sensitive than I ever realised. As little as a sixteenth of a turn made a significant difference to the CO reading, from maybe five per cent to three per cent even with just one carb being adjusted. So, increment by increment, moving from one carb to the other and back again, I reached the point where the idle was smooth, pick-up was clean and CO was stable between 2.5 and three per cent.
Next, the road test. No black smoke, slightly softer response from low revs but significantly keener at high revs. In fact, it’s the revviest it’s ever been, and it doesn’t smell either.
Most people don’t have a gas analyser, but you can always ask for an emissions test during an MOT even if the car doesn’t need one. Judging by how smelly many classics are, as you discover when you follow them, a lot of owners could do with information on their cars’ CO output – and, by extension, the amount of unburnt hydrocarbons that go with a high CO reading. Then they could do something about it, and the rest of humanity would love our funny old cars a bit more.
John Simister has been at the heart of British motoring journalism for more than 30 years. A classic enthusiast, he owns a Saab 96 and Sunbeam Stiletto.