Category - Tips

Make Your Own Screenwash Concentrate

Smearing windscreen in rainI’ve mentioned this in the smearing windscreens article, but winter is the time of year where it gets wet and cold (well, certainly wet), and along with the salt spreading a lot of crap gets thrown on to your glass and builds up into a nasty film that doesn’t easily wash off.

I’m always surprised that some people – including driving instructors – only put water in their wash bottles. And they try to justify it! But water on its own simply does not have sufficient wetting properties to attack oil, wax, and grease stuck on the glass. You know when it’s there, because you get that mosaic pattern left behind when you wipe in the wet.

You need a good detergent to clean off oily deposits, and a small amount of alcohol to assist with wetting. Alcohol also functions as an antifreeze when present in higher quantities, so whereas water will freeze at 0°C, a proper screen wash solution containing alcohol will freeze at a lower temperature depending on how you mix it – as low as -9°C.

You can buy two types in the stores – concentrated, or ready-to-use. With the former, you dilute it yourself depending on the weather outside, and with the latter you have to buy the correct type (they do ‘summer’ and ‘winter’ mixes, with the summer one containing very little alcohol). In most cases, the ‘concentrated’ stuff can be used neat and will protect to between -6°C  and -9°C depending on the brand. Some types claim as low as -20°C, but these are specialist ones and they likely contain other chemicals, since alcohol alone to provide that level of freeze protection would be quite dangerous because of its flammability.

The price of typical concentrated screen wash varies from about £5 per 5L in summer, to about £8 in winter (when you need it the most). The ready-to-use stuff is similarly priced, even though it is more dilute – so you are paying for water if you buy that. In a bad winter, with lots of rain and slush, I can easily get through 5L of washer fluid each week. I use less in summer, but over a year it can still mount up.

If you’re going to buy it, my advice is to stock up in summer when the prices are lower, and only get the concentrate so you’re not paying someone to dilute it for you. You often get BOGOF offers in summer.

However, it can be cheaper to make your own, and it is certainly more convenient. I got the idea when I had a freeze up one time (I was late switching to my winter mix in the first of the two cold winters we had about ten years ago), and solved the immediate problem by nipping into a hardware store and buying a bottle of methylated spirits. Adding that to my wash bottle depressed the freezing point and I was running again within 30 minutes. So then I thought why not make my own?

Washer fluid essentially needs to do two things:

  • clean
  • not freeze when it gets cold

It’s basically just a mixture of alcohol and water with a bit of detergent. And some smelly stuff and dye if you are going the whole hog with it.

For a normal screen wash, the recipe below is what I now use. In a 5L bottle, I place the following:

  • 10g Alcohol Ethoxylate
  • 50g Butyl Glycol
  • Ethanol
  • Fragrance
  • Colouring
  • Water to make up to 5L

The amount of Ethanol depends on the temperature you want to protect down to. To protect to around -2°C, 250mls of Ethanol is all you need (this is my Summer mix, since Ethanol also acts as a wetting agent and it helps to get rid of tree sap). To protect to -4°C, you need 500mls of Ethanol, 750mls protects down to around -6°C to -7°C, and 1L protects down to -9°C. Any more Ethanol in the mixture than that and the solution (especially its vapour) becomes potentially highly flammable. I adjust the amount depending on how cold it is, but I switch to at least 500mls around November each year.

Surprisingly, the water you use is quite important. Tap water is likely to leave water marks on the glass when it dries because of the dissolved salts in it. For many years, I used boiled rainwater, but these days I use the condensate from a home dehumidifier.

I buy Alcohol Ethoxylate and Butyl Glycol from Mistral Industrial Chemicals. At the time of this update, 1L of Alcohol Ethoxylate costs £15 and 1L of Butyl Glycol costs £16.99. The total value of these in each 5L batch of my screen wash is therefore just under 16p.

Ethanol is the most expensive ingredient. I currently buy mine from Liquipak. To keep the overall cost down, I buy 20L at a time, so a batch of my screen wash set to protect me to -9°C would contain Ethanol to the value of £4. A Summer mix would contain about £1’s worth.

I latched on to Alcohol Ethoxylate and Butyl Glycol from reading the Safety Data Sheets from various manufacturers of commercial solutions, and worked out a recipe from there.

A brief aside…

Some years ago I was having major problems cleaning my windscreen on new lease vehicles when I received them. There was something on them that gave the mosaic effect in the wet, but absolutely nothing would get it off.

Eventually, I found that Sugar Soap would. Sugar Soap is used by builders and decorators for degreasing walls and paintwork before painting, and I found it did remove the stubborn film from my windscreens.

Then, a few years ago, I was snooping around the forecourt while my car was being valeted at a hand car wash. I was intrigued by all the things they sprayed on the car which got it sparkling clean, so I wanted to find out what they were using. This was when I discovered Traffic Film Remover (TFR).

I tried using Sugar Soap in my screen wash, but it left a heavy residue when it dried. For several years I used TFR, which was much better (and very effective), but it still left streaks when it dried which I wasn’t happy with. This is why I came up with this latest recipe.

However, if your windscreen picks up a lot of wax from car washes, and other residues from the road, screen wash alone won’t completely remove it. In fact, you can completely degrease your windscreen in the visible areas, but it you leave even a trace of wax on the wiper blades or – worse – in the space where they sit when they aren’t wiping (it gets pushed down there and acts as an ink well), it gets spread pretty quickly back on to the main area of the glass.

An occasional deep clean using Sugar Soap or TFR is still a good idea, therefore. You can get Sugar Soap on Amazon, or at the local Screwfix depots and such like. You can get TFR (among other places, including Amazon) from JennyChem. And if you do decide to order directly from JennyChem, use the discount code BAYJC8628 to get 5% off.

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Alcohol Ethoxylate and Butyl Glycol are the same agents used in commercial screen washes. They are relatively non-foaming, and are designed to attack the kind of stuff you get thrown up on to your glass while you are driving. Don’t try using Fairy Liquid or other household detergents – you’ll have bubble blowing down the street, and it doesn’t work for this purpose anyway at the concentrations it is intended to be used at.

Personally, I make my screen wash fluid ready-to-use as I need it (I make three or four batches at a time and just keep them on hand, making more as required). In summer, I use the minimum amount of Ethanol, and in Winter I just up it depending on how cold it is outside based on those freezing points I mentioned earlier.

As for the fragrance, I found a concentrated Apple scent specifically for car detailing applications like this. It is manufactured by Koch Chemie in Germany, and is called Duftstoff Apfel. If anyone wants to know where to buy it, drop me a line using the Contact Form. And the colouring I use is just three drops of food dye.

How can I prepare for cold temperatures?

Use common sense. If it’s warm, you don’t need a low-temperature screen wash mix, since the higher alcohol content is just a waste of money. But you do still need decent cleaning power for the bugs and tree sap you’re going to get. However, if it gets very cold, you don’t want a freeze-up, so be ready to alter your mix accordingly.

For the recipe I have given here, assuming you have made it to protect down to -6°C to -7°C (750mls Ethanol), you can dilute it 1:1 or 1:2 with water and it will still clean your windscreen. As I say, I make mine as I need it, so I always have the full detergent effect.

Can I make it with more alcohol in it?

Yes, but be careful. Ethanol is flammable, even in water mixtures. On its own, Ethanol has a flash point of 14°C (that means that at that temperature and above, a combustible vapour exists above it that can easily be ignited). A 10% solution in water has a flash point of 49°C, which is much safer. A 20% solution has a flash point of 36°C, which is still safe unless you store it in a very hot place. A 30% solution has a flash point of 29°C, and this is quite likely to be encountered in hot weather. My advice is not to exceed about 20-25% of ethanol.

Do not carry a strong Winter mix in your car in Summer. And definitely do not carry significant quantities of neat Ethanol at any time.

Can I use isopropanol instead?

Also known a Propan-2-ol, 2-Propanol, and Isopropyl Alcohol (IPA).

Short answer, yes – but only if the it’s a few degrees below zero. IPA has a lower flash point than ethanol, and any solution above 20% is potentially risky. IPA also has a very distinctive smell.

Can I use Methanol?

I’m just going to say no. It’s poisonous even in small quantities (it can make you go blind), and could be dangerous if inhaled regularly, so for that reason you should not use it.

Can I use methylated spirits?

Usually, this contains methanol as the denaturant – though sometimes other chemicals are used. It also has a strong smell. Apart from the time I used it in an emergency, I would advise against it. However, if you can find ‘denatured ethanol’ or ‘denatured ethyl alcohol’, and can be sure it doesn’t have methanol in it, that would be fine. It’s usually (not always) the blue stuff that contains methanol.

Can I just use water?

Water on its own is no good. If the temperature falls, it will freeze. Even if it doesn’t freeze in your main washer bottle, it will in the pipes and at the nozzles, and freezing water is quite capable of splitting pipes or closed containers. Attempting to use your screen washer pump if there is no liquid water inside could burn out the motor.

Water alone doesn’t clean many things off the glass – it won’t touch oil, grease, or squashed insects, and it will struggle with tree sap.

Remember that if you are driving without the ability to keep your windscreen clear, you are committing an offence. The Road Vehicles (Construction and Use) Regulations 1986 says:

Every wiper and washer fitted in accordance with this regulation shall at all times while a vehicle is being used on a road be maintained in efficient working order and be properly adjusted.

Arguably, you are not complying with this if you just use water. If it freezes (or the bottle is empty) and you drive, you’re definitely not complying with it. It is shocking that some ADIs are apparently doing this.

Can you dilute ready to use screenwash?

Of course you can – certainly in Summer. It’s not a magic potion – just a mixture of water, alcohol, and detergent. I wouldn’t dilute the ready-to-use stuff more than about 50:50 with water, though, because the detergent probably wouldn’t do its job properly.


Fuel Costs, Fuel Cards, And Credit Cards

Asda Cashback Plus credit cardI’ve never used a fuel card, and for a good reason. I’ve been approached many times over the years (damned Yellow Pages) by companies offering me one, but the simple fact is that I have never been convinced that any savings are great enough, real enough, or reliable enough. Not for me, at any rate.

You see, when you look at what fuel card providers say, it’s always something like “save an average of 3p per litre against the national average forecourt price”. It’s that bit in bold which is the fly in the ointment. Fuel in Nottingham is – as long as you stay away from city centre garages – well below the national average in terms of cost per litre. At the time of writing, a litre of diesel costs me 125p, and yet the national average is apparently 132p. I would only ever “save” money if I sought out one of the joker garages around this way who charge this much, which would be stupid if I can already buy it at full price elsewhere for 7p less.

But what if there was a way to get a discount even on the lowest fuel prices? Well, there is – and it works all the time, no matter what the advertised price on the forecourt is, and it works anywhere.

I shop regularly in Asda, and my average weekly spend on groceries there is around £150. I also buy my fuel from Asda (it is the same quality as the equivalent basic grade from anywhere else), and my average spend on that is also around £150. A total of £300.

A few years ago, I came across Asda’s Cashback Credit Card Plus. It offered 2% cashback on virtually all purchases from Asda – crucially, including fuel. And although I had once vowed never to have another credit card as long as I lived, I was now in a position to be able to pay off an entire credit card bill each month without blinking, and since it would actually save me money I decided to try it. It works like this.

My weekly fuel spend attracts a cashback figure of £3. The quantity of fuel involved is about 120 litres at 125p per litre, so that equates to a discount of 2.5p per litre. But since I also spend the same amount on groceries, I get another £3 cashback with that, which means another 2.5p discount if I apply it to my fuel (whichever way you look at it, it’s money in my pocket). It equates to a saving of about £300 a year.

Cashback is redeemed by way of a voucher. Each time you use your card, cashback is added to your account, and when you’re ready you just choose an amount from your cashback balance and print off a voucher. You can’t use the voucher to pay for fuel directly, but since I already shop in Asda I just use it there. Obviously, you have to factor it in appropriately when you complete your tax return, but that doesn’t stop it being a saving on fuel costs.

Although the 2% cashback is only on Asda purchases, you also get 0.2% cashback on all other purchases made using your card. I know that 0.2% might not seem much, but buying a TV or something similarly expensive attracts up to another £5, and another 5p per litre discount for a week. As long as you clear your account each month, there’s no interest. Basically, the more you use your credit card for, the more cashback you get.

Unfortunately, the Cashback Plus card is not currently available to new applicants (since June 2019), but there is still the basic Asda credit card, which gives 1% cashback (and 0.2% on non-Asda purchases). This is still better than most cashback (and fuel card) deals out there right now if you are in an area which has below average fuel prices.


DVSA: Find Your Lost Theory Test Certificate Number

I wrote this article way back in 2012. At the time, DVSA had just launched a new facility where you could find your Theory Test Certificate (TTC) number online if you’d lost the paper sheet. Here’s the link to the feature on GOV.UK.

You need the number if you’re going to book your practical test – and note that I said the number, not the certificate itself.

A lot of pupils get worried that they need to take the actual TTC to their practical test, though. By that time, many will have lost or misplaced it (quite a few of mine have, and we usually only find out the night before or on the day, which allows me to wind them up a little). Indeed, the booking confirmation you get when you book your practical says you should take your licence and TTC along with you.

In all the years I have been an instructor, I can think of only one or two occasions where the examiner has asked to see it – and those were at least ten years ago. More recently, when a pupil has offered the TTC along with their licence, the examiner isn’t interested. They only want to see the licence.

If you think about it, you wouldn’t be able to book your practical if you hadn’t passed the theory, so it’s obvious you have done when you turn up on test day.

When any of my pupils starts to fret over not being able to find their TTC – and after I’m finished winding them up – I tell them the examiner won’t ask for it, and even if he or she does, just say that you didn’t get one or that the printer at the testing station was broken when you were there. None of them have ever had to do that, though, because the examiners simply don’t ask for it.

If you still have your TTC, take it along with you by all means. But don’t worry if you’ve lost it, because unless there is some problem with your booking, I cannot see any reason why they would demand to see it.


Sticking Your Badge On The Windscreen

Reel of magnetic tapeThis time of year must be when most ADIs renew their badges judging by the traffic recently. Someone asked me the best way to mount your badge in the car.

Well, when you get your badge, they also send you a plastic wallet to put it in, and this has a sticky side so you can attach it to the windscreen. It’s fine if it’s your first one, but I hate the damned thing. It’s too big and thick, and it messes up the glass. It gets degraded by the sun and you can’t switch it between cars (it keeps falling off if you try). And it starts to peel if you get screen cleaner anywhere near it, so the exposed sticky surface starts to attract dust and dirt, and looks bloody horrible after a few months.

There are all kinds of ‘aids’ available (at relatively huge cost for what they are), such as wallets and suckers, that you can get from eBay or specialist ADI suppliers. A lot of people apparently use Blu Tac, and some even go for Sellotape or packing tape. These mess up your windscreen, too – wit the added benefit being that they look like crap! And Blu Tac softens when it gets warm and your badge is likely to fall off (I once tried it for keeping cables tucked around the edge of the windscreen, and found that out).

I make my own mounts. I got the idea many years ago when I installed fly screens on windows in my house. They’re attached using magnetic tape – a bit like the stuff inside fridge doors (well, a lot like it, in fact).

Magnetic tape comes in two parts – A and B – representing different magnetic poles. Basically, A is attracted to B, but A will repulse A, and B will repulse B. So what you do is buy a length of each part, then cut four 1cm pieces of each. Stick a piece of side A in each corner of your badge (the tape has a peel-off adhesive back). Attach the four pieces of side B magnetically to these, then peel off the backing. Now push the whole thing carefully on to the windscreen where you want it (make sure the glass is clean and grease-free before you do this). You now have a secure magnetic mount, and you can easily take your badge off whenever you need to.

Magnetic tape costs as little as about £2 per metre, so £4 for a metre each of part A and part B and you’ll be set up for at least 20 badges. I don’t think many ADIs will see more than 10 – even if they do the job for their entire working lives. I’ve seen a few cars using this method now.


Using The Clutch And Brake

Another update to an older post, which has seen an increased number of hits recently.

A while ago, I suddenly started getting hits from someone (the same person) searching using “will you fail if you use clutch brake”. I’m not quite sure what they were asking, so here’s a summary of how to control the car (assuming you know the basics, of course).Car pedals in footwell

Imagine you’re approaching a t-junction to turn right. Imagine it is a slight downward slope. So, on your approach you will look at what is going on around you, assess it, decide what you’re going to do once to arrive, then do it. Basically, this will either be “go” or “don’t go”. I am guessing that the question people keep asking is based on the “don’t go” option, and they want to know how they should handle it.

So, you’ve arrived at the junction and had to stop. You’ve put the car into 1st gear, you’ve got the clutch down, and the footbrake on. The options you have are:

  • if you can see it is going to be clear to go after a couple of cars have passed, you don’t need to use the handbrake
  • if you’re going to wait for any significant length of time (e.g. if you can’t tell when it is going to be clear), use the handbrake and release the footbrake
  • when you see a gap coming, get ready
  • once it is clear, drive away normally

Now imagine the exact same situation, except that you are going up a slight incline. You get to the give way lines at the junction. Your options are now:

  • if you can see it will be clear to go after a few cars, you could use the upward gradient along with a little gas/bite to slow the car to a crawl, and time your arrival to meet the gap (you could do this in 2nd gear, though 1st gear is most likely the best option)
  • you could use the gradient to stop, and hold the car still using gas/bite, then just drive away from this position when the gap appears
  • you could stop, apply the handbrake, then find the gas/bite and take the handbrake off again to meet the gap when it comes
  • if you have to wait for any significant length of time, use the handbrake anyway

I think this is what the question is about: is it OK to hold the car on gas/bite (i.e. to “ride the clutch”). The answer is yes – as long as it isn’t to excess and you’re in control . The driving examiner will look at how you use the clutch in these situations.

When you are out on the road, look at how many cars rock back and forth at traffic lights (so not good at holding it on the bite). Look at how many people sit with the brake lights on (so probably not using  the handbrake at all). Look how many people roll back when they move off (so not good at finding the bite).

Riding the clutch properly takes practice if you want to avoid it going wrong, and not many people are as good as they think they are at controlling the car this way, which is why you see these things when you are out there. The drivers involved are often just lazy, and if you do it like that on your test then you are asking for trouble. Be careful, and don’t be afraid of the handbrake (although try to avoid using it for every little pause).

It’s worth pointing out that holding the car at the bite point too much wears down the clutch plates. A new clutch plate should last for 60-100,000 miles or more. If you ride it a lot – and badly – it can fail in less than 20,000 miles. And since they cost several hundred pounds to replace (my old Citroen Xantia cost me £395 + VAT when I had it done about 12 years ago, and one of my ex-pupils recently told me he’d been quoted not much less than £1,000 for his Mondeo), it isn’t something you want to be having replaced regularly.

It isn’t written anywhere that you must be able to ride the clutch like an expert. The examiner doesn’t automatically expect you to drive like one, although if you do then he cannot fail to be impressed – which might work in your favour if you make a small mistake somewhere else. However, if you come to a set of lights (or a crossing) which have just changed to red and you make no attempt to use the handbrake, and you do it regularly or get into a mess because of it, you’re chasing down a fault.

One last thing: personally, I don’t like my pupils finding the bite when they have the footbrake on, so I don’t teach them to do it and I stop them doing it if they develop the habit while they’re with me (it can develop by itself when a pupil isn’t sure how to coordinate their feet). The reason is that without gas the risk of stalling – which is already quite high in a learner – is that much greater. But if I get someone who can already drive, I don’t try to stop them finding the bite with the footbrake on unless it causes them to stall, causes delays in moving away, or results in jerky control (which is very often does). The examiners will view it that way, too, and you won’t fail for it unless it leads to other problems.

Do you use the clutch to brake?

NO! You use the brake to brake – the clue is in the name. You only put the clutch down if:

  • you’re changing gear
  • you’re stopping
  • you’re going slowly and you are deliberately coasting to control the car

If you immediately put the clutch down when you want to slow down from normal speeds, the car will not decelerate at all except due to gravity. If you’re going down a hill or around a corner gravity or centrifugal force will actually make it speed up. It’s called “coasting”, and the lack of engine braking is one big reason why you shouldn’t coast around most corners or for extended distances.

If you want to slow down, the first thing you should do is take your foot off the gas. The engine will slow down, and if the clutch is up it will cause the wheels (and therefore the car) to slow down. This is what is known as “engine braking”. You lose all that if you put the clutch down and break the connection between the engine and wheels.

But should you never coast?

As I said above, you can coast at low speeds if you need to control the car (e.g. in slow-moving traffic) – after all, it would be stupid if you were travelling at 5mph (the slowest many cars will go with no gas and the clutch up) when everyone around you was travelling at 2mph. You coast a little every time you change gear or come to a halt. And some corners – very sharp ones, for example – lend themselves to coasting (partially, at least) because you have to go very slowly. Just make sure you regain full control by finding the bite as soon as it is safe to do so.

If you’ve had someone teach you to change down through the gears (“sequential changing”) instead of just slowing down and going into the one you need, you should not put the clutch down and keep it down while you change through all the gears. The whole point of sequential changing is that you bring the clutch up after each gear change to utilise engine braking.

So are you saying it’s OK to coast?

People have a major hang-up over the issue of coasting, and even most instructors (and driving books) just think of it as riding along at speed in neutral, or free-wheeling around corners with the clutch down. Both of those things are bad, and they’re what gives coasting a deserved bad name.

However, coasting is a description of something, not a chronic illness. As soon as you pull over and stop the car, you have to coast a little. When you change gear, you coast a little. When you stop at traffic lights, you coast a little. And when you are moving very slowly, there comes a point where you have to coast, otherwise you could end up driving into the back of someone or something.

So, when you do a turn in the road, if you don’t coast at least a little, you’re likely to end up on the pavement or ramming hard into the kerb. At very low speeds in heavy traffic, coasting – in the sense of describing the control technique used – is a useful and essential tool. But this does not mean you should fling the car around corners on two wheels with the clutch down or listen to your taxi driver when he tells you coasting down hills in neutral saves on fuel. Coasting like that is dangerous.