Preventive maintenance is of paramount importance to ensure that the system works properly. Therefore, all automotive hoses, as well as the entire cooling system, should be inspected at least every 6 months to avoid flaws and leaks. Automotive hoses are generally installed in the same way, being attached to a pipe or fitting (inlet or outlet) and fastened with the use of clamps.


Before changing a hose it is important to know if it has liquid inside it.

If it has, the liquid must be drained completely.

Hose "glued" to the nozzle: most hoses are easily released as soon as the clamp is loosened. If this does not occur, rotate the workpiece around the workpiece by sliding it onto the surface. If the hose still does not come off, it must be cut off when it is replaced.

Check nozzle: Check nozzle for corrosion or burrs. This can damage the hose and make the system watertight. For the removal of waste, the nozzle should be cleaned using a sandpaper or metal brush. Note: Redouble care with plastic nozzles!

To facilitate installation and also avoid damaging the rubber at the time of assembly, use a lubricant, petroleum jelly, soap or a radiator additive.

Position the hose properly in place, taking care not to strain the rubber.

Always use a quick coupling clamp, or with a hexagon lock. Also use a wrench or a pipe.

Tip: First put the cuff and then the hose. This facilitates installation since the nozzle has a shoulder to ensure that the hose does not escape.

Avoid using a screwdriver as they have sharp tips that can damage the rubber by escaping the slit and damaging the rubber. This is the highest failure rate of hoses in the assembly


One of the most dangerous enemies of the hoses in the engine compartments of vehicles is the heat, which usually reaches a maximum of 110ºC. A hose damaged by excess heat, becomes hardened and lustrous, which leads to some cracks. These cracks, often irregular, wide and deep, do not always indicate that there has been heat damage.

If the hose is cracked and still flexible, the problem may have been caused by ozone or vibration.

Ozone causes tiny cracks arranged in small parallel lines across the length of the hose. Lion Polimers® hoses are manufactured with a compound called EPDM that resists ozone completely.

Cracks present at the edges of the hoses are usually a result of clamps that are tightened in excess or incorrectly positioned over the nozzle. Proper installation is paramount for the perfect functioning of the cooling system.

Oil is the worst enemy of a rubber hose. A hose contaminated with oil appears swollen and softened. Should this occur, the hose must be replaced and the oil leak needs to be readily contained.




Appearance: As with electrochemical degradation, heat damage can occur internally and are difficult to detect by physical appearance. One sign of internal damage is swelling.

Problem: Overheating can overload the fibers, by dilation inside the hose, deteriorating it. As the engine compartments are getting smaller and more compact, the temperature under the hood increases.

Solution: Always observe the state of the cooling system at the fluid levels.


Appearance: small parallel cracks in the hose cover, although there is no hardening.

Problem: The increase in ozone, caused by pollution, directly attacks the rubber compounds. Small cracks occur mainly in bends and places of fixation. These cracks allow air contaminants to invade and weaken the hose.

Solution: Install Lion Polimers® (Ethylene-propylene-diene) hoses, a compound not affected by ozone.


Appearance: scratched, torn or worn cover.

Problem: Abrasion occurs when the hose is cut or perforated by friction of the contact of the hoses with each other or with some fixed element. An improperly attached hose may be sanded when it comes into contact with any component in the engine, such as an alternator belt, fan blade, or even a pulley.

Solution: Replace damaged hose. Do not install a new part and attach it properly to the correct length.


Appearance: The damaged hose becomes soft, sticky or spongy to the touch. Lumps and bumps also appear.

Problem: the oil derivatives chemically react with the compounds of the hose weakening its bond structure. This causes the hose to soften, swell and separate into layers leading to failure. The oil can attack both the outer and inner surfaces of the hose.

Solution: External Damage - Replace damaged hose and eliminate any source of leak. Internal Damage - Replace hose and cooling fluid. Use the type of fluid recommended for your application.


Appearance: Moisture, crystallization of the liquid in the nozzle and dripping form around the clamps.

Problem: In addition to insufficient torque in the clamp, leakage is usually caused by the deteriorated state of the hose.

Solution: Clamp - In more problematic areas, it is recommended to wrap the clamps with each hose change, thus preventing future leaks, as well as using the correct tightening. Excessive tightening can damage the hose.