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I've been around long enough to have seen some eye opening events in the motor trade. Some were minor and some were damn right dangerous. Some revealed a lack of competence, some pure laziness and a number revealed the mechanic just hadn't moved with the times, unlike automotive technology.
When you pay good money to have your vehicle repaired by a professional mechanic you expect the repair work to be completed correctly and in accordance with the recommendations published by the vehicle's manufacturer or following industry standards which more or less amount to the same thing.
Behind the closed doors of a workshop you have no way of knowing if your vehicle is been maintained and repaired correctly. Unless you're there and watching the repairs being carried out and you are a professional mechanic yourself (in which case you'd be doing the repairs yourself) then you only have the repairer's word that the repairs were carried out correctly, and let's face it, who actually asks before they pay the bill?
But does it really matter? Yes it does.
Vehicle manufacturers spend hundreds of millions of pounds every year carrying out research and development to calculate the optimum settings for each vehicle they produce. They don't do it for the fun of it. They wont spend one penny more than necessary so the fact that they are willing to spend these millions speaks for itself.
There's no magic formula, guess work is 100% inaccurate and you can't make it up as you go along. Only expensive and time consuming research and testing can formulate the correct settings for each model derivative.
If the manufacturer gets it wrong or the repairer doesn't follow the manufacturer's recommendations then vehicle safety, performance and life expectancy will be reduced.
It's 50% unless the manufacturer says otherwiseA number of years ago I was in a garage in Hull talking to the owner about a problem he was having with one of his customer's car. At the time he was replacing the engine coolant on another vehicle and prior to my arrival he had drained the cooling system and had just replaced the bottom hose as I walked in.
While I was chatting to him he proceeded to measure out 1.5 litres of antifreeze and added this to the expansion bottle then filled the engine up with tap water from a watering can. This vehicle I knew had a cooling system capacity of 10 litres and therefore required 5 litres of antifreeze to comply with Ford's published recommendations.
I asked him why he had only added 1.5 litres of antifreeze. His answer showed a complete lack of understanding of modern cooling system additives and engines.
He told me he had read on the back of a bottle of antifreeze than a concentration of 15% antifreeze (85% water) would protect the vehicle's engine down to -8 Celsius. That's adequate he said, it rarely gets colder than -8.
Well he was as wrong about the temperature as he was about using only 15% antifreeze.
Modern engine cooling system additives, often referred to as antifreeze, perform far more functions than just preventing the water in the engine from freezing. Here's a list of the most important properties of antifreeze.
- Reduces the freezing point of the fluid in the cooling system.
- Increases the boiling point of the fluid in the cooling system.
- Reduces corrosion in engine and cooling system components.
- Reduces lime scale build up in the cooling system.
- Reduces foaming.
- Lubricates the water pump and thermostat.
The most important of these properties is corrosion prevention. When you have water, electricity and acidic compounds circulating in a metal engine you have the optimum environment for metal corrosion. This corrosion causes engine damage leading to failure, head gasket failure, reduced heat transfer and premature failure of cooling system components such as the water pump.
By adding only 1.5 litres of antifreeze the corrosion inhibiting additives in the new mix would quickly have become saturated by the corrosion already present in the engine and at 15% concentration there would be insufficient to prevent corrosion occurring. Should the vehicle's owner then have added water to top up the system this concentration would fall even lower.
The loser here is the vehicle's owner who would have left thinking their car was protected for the next couple of years but who faced an expensive engine repair when when the corrosion had caused enough internal engine damage. As for the garage owner, he will have been paid, no doubt the same amount as the job could have been done properly for and will benefit from his own incompetence when the vehicle returns for a new head gasket in future months.
One size doesn't fit allAs my late father used to say, it's bad when your car wont start but it's a disaster when it wont stop. Even if you neglect everything else you need good tyres and good brakes.
If you look through the handbook for your vehicle you'll see just how many combinations of tyre sizes are fitted to your vehicle across the different trim levels. Now look at the tyre pressure chart and you'll see this reflected in the different tyre pressure recommendations too.
As I mentioned earlier in this article, vehicle manufacturers spend a small fortune calculating the correct tyre size and pressure for each model and trim level, in this case in close collaboration with tyre manufacturers They don't do it for kicks.
There isn't a 'one size fits all' guide to correct tyre pressures. Every model and trim level combination is different and it's different for a reason.
I've lost count of how many times I've heard a mechanic tell me "A few pounds per square inch (PSI) wont make any noticeable different to the performance or safety of a vehicle".
Wrong, and dangerously so.
And it still makes me cringe every time I see a mechanic pick up a tyre inflator and without any regard for the correct pressures proceeds to inflate all the tyres to his own randomly generated idea of the correct pressure. Never mind the hundreds of thousands of pounds of research and development which has gone into publishing the correct tyre pressures, every vehicle gets 30PSI in every tyre because that's the way it is.
What the mechanic wont tell you is that he wont be driving the vehicle when it leaves the road due to insufficient tyre grip and kills or seriously injures the occupants.
And the cause is pure bone idle laziness because all workshops have the manufacturer's recommended tyre pressures in their technical data resources. But that involves opening a book and reading the correct, and well indexed page to find them.
I've just looked up the correct tyre pressures for a Vauxhall Corsa. In fact this happens to be the most popular Corsa model on the British roads today. I'm not providing details here of the trim level, tyre size or the vehicle's age in case somebody decides to use these in the belief they are correct for their car.
This specific model's tyre pressures are 31PSi for the front tyres and 23 PSI for the rear tyres. Why have Vauxhall listed these pressures down to an increment of 1PSI? Why haven't they rounded down the front tyre pressures to 30PSI and rounded up the rear tyre pressures to 25PSI? The answer is both simple and obvious.
During Vauxhall's extensive research and development testing of this vehicle they will have tried every combination of tyre size and pressure possible and they found that there were noticeable benefits to vehicle handling, tyre wear, tyre temperature, grip, water dispersal and driver comfort by having the front tyre pressures set at 31PSI and not 30PSI and the rears at 23PSI and not 24 or 25PSI.
And if you watch Formula One racing like I do you'll see this in action at every race. You can see for yourself drivers entering the pits to have their tyre pressures adjusted, but not by 1PSI, by a fraction of a PSI because in Formula One racing even 0.25PSI can change the handling characteristics of the racing car.
If it's 23PSI it's 23PSI for a reason. And the reason is vehicle safety because you only get one chance at getting it right.
It's 2007 and it's a spark plugAutomotive technology has moved on at a dramatic rate in previous decades but unfortunately some areas of the motor trade, and here I'm quite specific, some of the teaching fraternity, haven't.
Back when wheels had wooden rims and ignition coils were housed in glass jars the component installed in an engine to ignite the fuel and air mixture was called a sparking plug.
Now wheel rims are made of complex alloys and each cylinder has it's own ignition coil (Coil per Plug) and the component used to ignite the fuel and air mixture is called a spark plug.
But don't take my word for it. I am unable to find one vehicle or engine manufacturer or one spark(ing) plug manufacturer who calls this component a sparking plug. Go and have a look yourself at
NGK,
Champion and
Nippon, the biggest names in spark plugs and the world leaders and not a mention of the term sparking plugs.
So why do those responsible for educating the mechanics of the future not concede that terminology has moved on? Because for a lot of them they are totally detached from the modern motor industry. For a large number of them the only contact with the modern motor trade is their annual visit for an MOT test. For a small few it's the inside of a car showroom when they are selecting their brand new car.
When inside their warm and politically correct classrooms they are stuck with their outdated text books, a million miles away from the world they will eventually release their students into. They follow the teaching guidelines of examination bodies who are often equally detached from modern day life. A good example of this was an exam question which was presented to a student as part of his online examination.
Q. Where would you expect to to see a head pipe installed in an exhaust system?
A. What on earth is a head pipe?
The classrooms are filled with students who either shouldn't be there or don't want to be there, each has a price on his head amounting to thousands of pounds a year in government funding and the doors are wide open ensuring the maximum revenue benefit for the College rather than the highest quality trainees for the motor industry.
This country is screaming out for plumbers and builders but the motor vehicle teaching facilities are at bursting point whilst workshop employment is in decline.
And when these students don't make the grade at examination time you make sure you revise the questions with them 5 minutes before the retest, conveniently leaving the revision on the board, to ensure targets are met and results based government funding is achieved.
And I've seen it done first hand.
As an old head of department said to me and a group of others once. "If they (students) don't want to be here then get rid of them". I'd go further, a lot of those doing the teaching aren't fit for purpose and don't want to be there and the college's should be more proactive in getting rid of them.
Keywords:Auto Autos Automotive Automobile Automobiles Antifreeze Car Cars Coolant Education Garage Mechanic Spark Plug Safety Teaching Tyre Tyres Vehicle Vehicles Workshop United Kingdom UK
