The appearance of your vessel is often a reflection of the owner’s attitude towards the maintenance of the equipment, and boat-cap painting The top cowl is constantly exposed to the aggressive effects of salt or fresh water, ultraviolet radiation and the impacts of fine debris, and over time even the high-quality factory coating loses color, becomes covered with microcracks or cracks, exposing the metal or plastic of the base.
Restoration of the paint layer is not only a matter of aesthetics, but also an important element. maintenanceProperly selected and applied paint creates an additional barrier to protect the internal mechanisms from moisture and dust, and it is also an opportunity to personalize your unit, distinguishing it from the mass of standard gray or black models.
The restoration process requires careful preparation and adherence to the technology, otherwise the result may be disappointing after the first watering. In this article, we will discuss in detail the choice of materials, the stages of surface preparation and the nuances of coating, so that you can perform the work efficiently and long-lastingly.
Selection of materials and assessment of coverage status
Before starting work, you need to decide on the type of paint, because not all formulations are suitable for marine use. Yamaha or MercuryThe plastic casings of modern motors need elastic paints that will not crack when vibrating and thermally expanding.
The most popular choice among water engines is two-component polyurethane enamels, which form an extremely durable film that is resistant to gasoline, oil and salt water. However, working with them requires skills, since the life of the finished mixture is limited. Aerosol cans are suitable for local repair of chips, but for full repainting it is better to use paint applied with spray gun or brush (for specialized hammer formulations).
⚠️ Warning: Never use conventional car nitro-enamels or paints for interior work. UV and salt water will cause the coating to become shallow and peel off after 2-3 weeks of use.
Evaluate the condition of the current coating. If there are deep corrosion sites on the surface, they should be cleaned to metal. For plastic parts, it is important to check for deep cracks that may require prior puttying with a special composition for plastic.
Surface preparation and dismantling
Quality surface It's 80 percent successful, and you don't want to paint over old varnish or rust, because it's not going to last long, and the first step is to thoroughly wash the cap with a degreaser or a special cleaner to remove the oil film, the lubricant traces and the algae.
After cleaning, you're going to do a machining step, and the old coating is removed by a P80-P120 abrasive grinder, and your job is to create a risk (microscraps) that the new soil can catch on, and if there's corrosion on the metal, use a rust converter, but after it's dryed, you still have to traverse the surface.
- 🧼 Wash the surface thoroughly with warm water with a detergent to remove salt.
- 🔧 Remove all attachments: handles, stickers, oil level indicators and fuel hoses if they pass through the casing.
- 🛡️ Stick with paint tape and paper areas that are not subject to staining, such as internal stiffeners or lock attachments.
- 💨 Blow all the cracks with compressed air to remove abrasive dust from hard-to-reach places.
The final step is degreasing, and you can use an antisilicone or a special degreaser, rubbing the surface with a lilac-free wipe in one direction, and then you can't touch the surface with your hands in gloves, because the skin fat will worsen the adhesion.
☑️ Checklist of preparations
Printing and spatting of defects
If there are dents, deep scratches or corrosion marks on the surface of the cap, they must be removed before painting. This is done using a car polyester putty, applied with a spatula in thin layers, allowing each layer to dry completely according to the manufacturer's instructions.
Once dry, the putty is grinded, from the P120 abrasive to the P320 or P400, to level the surface and make the transition invisible. It's important not to overdo it or remove the excess around the site being repaired. The boundaries of the putty should be as flat as possible.
The next critical step is to apply soil, and for outboard motors, epoxy soils or acid (phosphate) soils for metal are best suited, which provide maximum protection against corrosion, and plastic must be applied to a special adhesive soil (primer), otherwise the paint will just tear off with film.
| Type of surface type | Recommended soil | Drying time (20°C) | Compatibility |
|---|---|---|---|
| Aluminum (corrosion-prone) | Acid (Vixen/Wash Primer) | 30-60 minutes. | All types of enamel |
| Aluminum (clean) | Epoxy two-component | 12:24 hours. | Polyurethane, Acryl |
| Plastic (ABS, PP) | Adhesive primer for plastic | 15-30 minutes | Acrylic enamel |
| Fiberglass | Polyester or Epoxy | 4-6 hours | All types |
The soil is applied in 2-3 thin layers with interlayer drying. After drying completely (it is better to wait a day), the surface is grinded with a P400-P600 abrasive under painting. The surface should become matte and smooth to the touch.
The Secret of Perfect Ground
When grinding the soil, use water (wet grinding) with abrasive P600-P800. This will help remove the risk from the previous abrasive and make the surface perfectly smooth, but before painting the part will need to be thoroughly dried and degreased.
Technology of coating paints
The painting process requires a clean, well-ventilated room with an air temperature of not less than +15 ° C and a humidity of not more than 70%. Dust is the main enemy of the painter, so it is recommended to moisten the floor in the room before starting work to nail the dust.
The paint must be thoroughly mixed and, if it is a two-component composition, mixed with the hardener in a strict proportion specified by the manufacturer. Mixing proportions You can't change it to the eye, otherwise the coating will either not dry or will be too brittle. If you use a spray gun, adjust the spray torch and pressure (usually 2-3 atmospheres).
Apply the paint in 2-3 thin layers. The first layer (dust) is applied very thinly to create a base; the second layer is the main, wet, but without leaks; the third layer may be required for color saturation. Between layers, be sure to maintain the interlayer drying time specified on the jar (usually 15-20 minutes).
⚠️ Warning: Do not try to paint the surface "stop" in one pass. A thick layer of paint is guaranteed to bubble or leak, especially on the vertical surfaces of the cap.
Keep the spray gun perpendicular to the surface at a distance of 15-20 cm Movements should be smooth, with overlapping the previous passage by 50%. Sharp movements or change in distance will lead to uneven color and defects of "shagrenous skin".
Use a tack cloth just before applying each layer of paint to remove the settled dust, which will greatly improve the final look of the coating.
Lacquering and finishing
If you have used a metallic or mother of pearl paint, applying a transparent (2K varnish) varnish is a must. The varnish protects the pigment layer from burnout and mechanical damage, and also gives depth to the color. For outboard motors, choose varnishes with UV filters.
It's applied in the same way as paint, in 2 layers. The first layer is made drier, the second one is wet, glossy. It's important to keep dust out of the varnish, because it's the hardest thing to fix. After applying the varnish, the part must dry in a warm, dust-free room for at least 24 hours.
After full polymerization (which can last up to 7-14 days to gain full strength), the surface can be polished. The polish removes the fine shaven (orange peel) and gives a mirror shine. Use a polishing machine with a medium-strength circle and polish for freshly painted surfaces.
- 🚫 Do not wash your stained cap with aggressive chemicals in the first 2 weeks after painting.
- ✨ For polishing, use compositions with minimal abrasiveness so as not to wipe the varnish.
- 🌡️ Avoid a sharp temperature drop during drying, this can cause turbidity of the varnish.
Frequent mistakes and how to avoid them
Even experienced craftsmen can make mistakes that will ruin the appearance. carpetOne of the most common problems is poor adhesion, where the paint flakes off in layers, almost always because of poor degreasing or using the wrong soil.
Another common problem is shaven or orange peel, which is caused by too viscous paint, wrong pressure in the spray gun, or failure to comply with the temperature regime, so if the shaven is strong, you have to grind the surface and repaint it.
Paint flows ("tears") occur when you apply a layer that is too thick, you can remove a small flow after you dry it completely with grinding and polishing, but a large flow will require local repainting, and you often find the varnish matte caused by high humidity in the room or getting moisture into the paint.
The main secret of durability of painting outboard motor is not a brand of paint, but the quality of surface preparation and compliance with the temperature and humidity regime during drying.
Can I paint the engine with ordinary car enamel?
Technically, it can, but the life of this coating on water will be much shorter. Car paints are not always designed for constant exposure to salt water and can lose color or start to bubble faster.
How much paint does the engine cap dry?
The drying time "on the stick" is 1-2 hours, but full polymerization takes from 7 to 14 days. It is recommended to operate the motor (letting out on the water) not earlier than 3-5 days after painting, so that the coating has gained sufficient strength.
Do I need to remove the cap from the engine for painting?
It is highly recommended to remove the top casing, painting on the engine is fraught with paint on the carburetor, candles, electricians and lower unit, and also remove the cap is necessary for high-quality processing of the inner edges and places of adjoining.
How to remove small scratches without a full repainting?
For small scratches that do not reach the metal, you can use a restoration pencil (touch-up pen) in the color of the engine or gently paint the defect with a thin brush, pre-fatted and sanded only the scratch itself.