The hood, trunk lid or tailgate, doors and front fenders are bolted together and can therefore be removed and replaced without any problems. But in this case, during installation, it is imperative to observe the necessary clearances, otherwise, for example, the door may knock, or increased air flow noise will be observed during movement.
The gap must always run parallel, which means that the distance between the body parts must be the same along the entire length of the gap. Permissible deviations should not exceed 1 mm.
Attention! If, as part of the body work, work will be performed on the electrical system of the car, be sure to disconnect the wire terminal «masses» (-) from the battery see relevant chapter. Electrical work includes even the simple disconnection of an electrical wire.
Attention! Numerous elements of body cladding are fixed with so-called expanding clamps. Expanding latches damaged during removal should be replaced, and new ones should be put in place of the missing ones.
Safety rules for body work
To perform welding work, a flash butt welding machine should be used.
The use of gas welding is permissible only in cases where flash butt welding is not possible, for example, due to insufficient space between body parts.
When performing welding or other work accompanied by the formation of sparks, the battery should be disconnected by removing the terminals from the terminals and carefully insulate both poles of the battery.
When performing welding work near the battery, it must be removed.
Attention! If the radio has a passcode, it will be deleted when the battery is disconnected. After connecting the battery, the radio can only be switched on after entering the required code or by using the services of a Mercedes workshop or the radio manufacturer. Therefore, before disconnecting the battery, check and write down the entered code.
Attention! Body work is accompanied by strong vibration, for example, from hammer blows. For this reason, always turn off the ignition, and disconnect the power wire terminals from the battery terminals.
Otherwise, the airbag may deploy. Familiarize yourself with the safety precautions regarding the handling of airbags.
Cars with air conditioning
Do not weld or solder soft or hard solder parts of the filled air conditioner. This also applies to welding and soldering work in general, if there is a risk that the parts of the air conditioner will heat up.
Attention! Do not open the air conditioner coolant circulation system. The refrigerant can cause frostbite if it comes into contact with the skin. If refrigerant comes into contact with the skin, wash the affected area with cold water for 15 minutes. Coolant is colorless and odorless and is heavier than air. Leaking refrigerant from the air conditioner can lead to suffocation when in a work pit on the bottom of a car, especially since the refrigerant is odorless and colorless, a person does not feel danger.
Drying paintwork
As part of the repair work, heating the car in the dryer or its chamber is allowed within the limits of no higher than + 70°С. Otherwise, electronic control devices may be damaged. In addition, high pressure is generated in the air conditioner, which can lead to a rupture of the unit.
Removing the anti-corrosion coating of the bottom
To protect the bottom and wheel arches from corrosion, they are covered with a polyvinyl chloride compound.
PVC protection in repair areas can be removed with a metal brush or heated with a hair dryer to a temperature of +180°C and removed with a spatula.
Attention! When the polyvinyl chloride layer is heated above +180°C, hydrochloric acid is formed, which contributes to the formation of rust, and vapors harmful to health.