BMW 525i M-Sport (Part 1)

Recently, we were engaged to undertake a ‘Major Paint Correction Detail’ on a 2001 BMW 525i M-Sport. The owner had recently acquired the vehicle and was disappointed with the paint finish and overall appearance of his new ride.

The remit was to focus primarily on the painted surfaces, with the owner quite happy to take care of the vehicle’s interior himself. Additionally, we were requested to remove the wheels and ensure that they were thoroughly cleaned.


On delivery, the owner’s concerns became immediately apparent, with harsh swirl marks clearly ruining the paint’s reflectivity and clarity – especially on the bonnet.

Other panels had also been subjected to abrasive cleaning.

And the boot lid was another area that the owner was particularly disappointed with.

In addition, there was unfortunate ‘kerb’ damage to each of the vehicle’s rims. While we do not provide ‘wheel repair’ services, we would endeavor to make these as presentable as possible.

Remedial Tutelage:

Before approaching the vehicle’s painted panels, it’s important to attend to some prerequisite tasks. Generally, we tackle particularly dirty areas, such as the vehicle’s engine bay, wheels, arches and sills/shuts ahead of a traditional ‘wash’ process to ensure that the vehicle is cleaned in the safest possible manner. This also ensures that we don’t end up rinsing dirt onto areas that have already been cleaned.

Engine Bay

The German powerplant was in pretty good shape:

With only a light dusting of dirt scattered throughout the engine bay:

As precaution, the exposed electrical connections were covered...

…and the engine was rinsed clean at low pressure with a mild cleanser.

Wheels & Arches

As previously mentioned, this was to be a ‘Wheels Off’ detail.

"Meguiars Super Degreaser" was applied to the wheel arches and they were scrubbed clean with a stiff bristled brush.

The rear wheels came off looking reasonably grubby. The cleansing process for these was to scrub the tyre walls with "Meguiars Super Degreaser", and to clean the wheel rim with "Menzerna 7.5 Wheel Gel". Once clean, the rims are treated with a "Tar & Glue Remover" to clear all residue from old "wheel weights" and stubborn tar spots.

The rims are then treated to a coat of "Poorboy’s Wheel Sealant", leaving them looking fantastic.

The front rims were showing significantly greater etching and staining, possibly due to a more aggressive brake pad being employed…

…a thorough scrubbing with the Menzerna Wheel Gel still left this behind:

Stepping up the ‘aggressiveness’ of the cleaning process, we turned to "Meguiar’s Wheel Brightener", with the following results.

And, of course, finished off with a coat of "Poorboy’s Wheel Sealant"!

Foam Bath

Prior to any polishing, or paint correction of any kind, it is imperative that the paint surface is impeccably clean. To achieve this in the most ‘gentle’ way possible, the vehicle is first covered in a thick blanket of foam. This is achieved with "Meguiar’s Hyperwash", applied to the vehicle via an "Autobrite UK Foam Lance".

And left to dwell for 5 minutes before being rinsed off.

Hand Wash

With as much dirt as possible removed from the vehicle without direct contact, it was time to complete the wash process with a hand wash via a Lambswool Mitt and Meguiars Shampoo Plus.

A lambswool (or microfibre) mitt should always be used for 'contact' washing of a vehicle's painted surfaces. Particles of grit and dirt on the paint are the primary cause of swirls on modern vehicles with 'clear coat' paint. Regular sponges cause the grit to be trapped against the surface of the paint and dragged across it. (Even worse still are the brushes at self-service or automatic carwashes.) The plush mitt however will draw the dirt away from the paint surface, deep into the fibers of the wool, thus preventing it from inflicting further damage.

Also notice the separate buckets for 'wash' and 'rinse' action. This is the safest and most effective way to clean a vehicle's paint. The Mitt is soaked in the 60° C Shampoo Plus solution which has a "Low-Suds / High-Lubricity" formula and then worked over the vehicle. After each panel, the Mitt is cleaned off in the 'rinse' bucket, dislodging any dirt picked up off the car, before being re-soaked in the shampoo.

If you consider the use of two buckets ‘overkill’, consider the state of the rinse bucket after completing the wash:

Would you consider wiping your car with anything soaked in the bucket on the right?

Clay Treatment

The final step in ensuring a perfectly clean paint surface is the removal of bonded contaminants with a detailing clay bar. This can include tar spots, tree sap or industrial fallout, all of which contribute to making the paint surface rough to the touch and dull to look at. In this instance, a Meguiars ‘Mild Professional Detailing Clay’ bar was used with Meguiars Last Touch (diluted 1:1) as lubrication.

Very little contamination was removed from the vehicle, with the following picture being representative of the amount of bonded material on each panel.

Even small amounts of contamination can dramatically reduce the effectiveness of any subsequent polishing. If not removed, the material will be drawn into the polishing pad, and potentially instill scratches to the paint surface throughout the machining process - so it is well worth taking the time to ensure that the paint is perfectly clean and smooth prior to any form of correction.

The vehicle was then given a final rinse with the pressure washer and then dried off with a "Sonus Der Wonder Microfibre Drying Towel".

With the BMW's painted surfaces now perfectly clean and smooth, we can move the vehicle inside and commence corrective polishing...