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how to use vasco prewash

How to use Vasco Prewash? Leave a comment

Why do I use Vasco Prewash?

I get a lot of questions about Vasco Prewash, I’ve been using it since 2014, so I think I can say the most about this product.
Why do I use Vasco for all my services? The reason is simple; tar is on every car we use daily. I have not yet seen a car that does not have any traces of tar. By the time I found Vasco, I was using various tar removers. I tested at least 15 different tar removers.

All of them were solvent-based products, most of them worked. Still, the reasonably safe ones required more labour, strong ones worked quick, but from time to time, they caused reactions with surfaces, e.g. plastics, lights etc., even minor reactions with panels that had been resprayed or in the case of pressed number plates; solvent tar removers removed paint from the plates.vasco prewash dirty car auto detailing ireland

Therefore I was constantly looking for something safe for the surface and worked effectively. When I got the Vasco a few years ago, first of all, I tested it over long periods on my test panel and a couple of various plastics. I have never noticed any bad reactions on these surfaces. It’s definately the safest tar remover I have ever come across. Another reason why I use it is that I hated removing tar with the standard method. Vasco Prewash, for me, kills a few birds with one stone.

How to get the best out of this tar remover?


The product doesn’t do any magic, and it may not work for everyone. It works perfectly for me because I know what I can expect from it, and generally, when I am using any product, I try to find out its capabilities to get the most out of it. Vasco Prewash is not a solvent tar remover. It works slowly, so if we want to achieve the desired effect, it should be left on a surface to work for way longer than solvent tar removers. Longer dwelling time is the disadvantage of this product, but the possibility of contactless tar removal rewards it big time. With a bit of planning, I never felt that I had to wait for the product to do its job due to its slow operation.

It is not a product for everyone. People who offer 2-4 hour services. May is more likely to not find the use of the product due to lack of time. I often spray a vehicle and leave it overnight, rinse it off in the morning, and have the vehicle pre-cleaned from the heaviest dirt and tar. For dirty vehicles with the more severe build-up of tar, Vasco needs to be left on a car for 45 minutes -2 hours to dissolve heavy spots of tar. This video shows how I use Vasco and how well it works when I let it do its job. In both cases, I applied the Vasco Prewash to a dirty car.


It does not work for me; what is the reason?

I have heard opinions that Vasco only removes 90% of the tar or doesn’t work too well. The product cannot select which dots of tar it will remove or how much tar it removes, so missing spots shouldn’t happen if we apply it evenly on the whole surface missing spots shouldn’t happen. I haven’t come across a product that would only remove a percentage of a contaminant and, at some point, would stop doing its job unless the product dries off before the job is done. If a product dissolves impurities, anyway, it will remove it thoroughly it is left on a surface for long enough.

Vasco, due to its gelly consistency, can work on the surface for a long time, but even though there are several reasons why we may miss some spots of tar after rinsing.
1. If you don’t shake the bottle before use. (this is one of the key reasons)
2. The product has been rinsed off before it dissolves tar spots. I always check if the most significant spots of tar are already dissolved, and only then do I rinse the car
3. We apply the product on the surface, but we ignore even coverage. Therefore the product did not react with all the tar

4. In the case of filthy cars with a layer of dirt of a few millimetres, and the product could not react with tar, it may fail too
5. When we apply the Vasco Prewash on a wet surface, which weakens its effect
6. The product dries off before rinsing. I always check if any places have dried up, especially if I leave them for a few hours. If it happens, I spray a delicate mist of the product and leave for 3-4 minutes and then rinse the car
7. Rinsing the car too fast, dissolved tar is very dense; rinsing off too quickly may also cause that we will miss spots.
8. Rinsing the car from the top, Vasco does not work so effectively after more extended contact with water. Therefore I always rinse the vehicle starting from the bottom. It works perfectly

                           Knowing the product is the key

By following these guides, I always remove the tar 99.9% contactless. My task is easy because I have an indoor wash bay, but many people use Vasco outside, and the product works very well for most of them.
The Vasco prewash fails as a typical prewash on filthy cars. When it comes to using it, I use Vasco mainly to remove tar. The product also softens dirt, but in some cases, especially if we do not wash the car for many months, it happens that we remove the tar, but some of the road films remain.

Therefore, after rinsing with Vasco, I always apply the foam on the car and leave it for a few minutes, then rinse off and then I have the vehicle prewashed very well. Another reason for using foam after Vasco is that I only use Vasco for places where tar may be present, i.e. the sides to the door handle level, the back, and the front bumper. There is no need to use Vasco on the bonnet and roof, saving the product.

Product cost: 1 litre of the product is enough for 2-3 cars when used with canyon trigger. So from the 1L bottle, it costs 5-7.5 euro per car, from a 5L container it costs 3-4.5 euro per car, and from a 25l container, when buying with a group discount, the cost of 1L of the product is about 6 euro per litre which gives the price of 2-3 euro per 1 car. Is it costly? This cost is meagre considering that I save a minimum of 30-40 minutes of my time compared to a standard tar removal, and I am also sure that I use a surface-safe agent.

Is the Vasco Prewash safe on cars with ceramic coatings?


To sum up, Vasco is not a product for everyone. The product has its limits and requirements. With proper use, it is a brilliant product. If too high expectations, it will fail like any other product on the market. I hope this helps people who want to know more about Vasco.

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