Thursday, April 17th, 2014

Repair Tips about Automotive Belts and Rubber Hoses

Mention the word RUBBER to any cross section of people and you would be shocked at how many different replies you can receive. A Frank Sinatra fan would probably think of his song “High Hopes”. Any mail man or delivery person would talk about the outer shoe covering that they wear to protect their walking shoes and keep their feet dry.

A high school senior with raging hormones…… well maybe we’ll skip that one. A tire salesman will immediately think of tire sales and a hardware store employee will send you to the gardening section. But ask a repair facility owner and he will immediately talk to you about BELTS AND HOSES.


Nothing Sexy about Rubber Hoses

Back in the day, the early automobiles cooled their engines by air, a concept that Volkswagen kept alive well into the 1980’s. In the early days of automobiles creature comforts were not in the highest priority. Most engines were mounted on solid mounts and vibrated accordingly.

A large radiator was in front of the vehicle and mounted to the chassis. In order to make sure that the coolant is able to get to the engine the radiator was connected to the engine via two rubber tubes that sent the water into the block and then back into the radiator to be cooled.

Enter the years of creature comforts. Now we have cooling hoses, heater hoses, and transmission cooler hoses, oil cooler hoses, A/C hoses and what used to be a belt that turned every component under the hood, sometimes as many as five belts.
Here is the issue of today’s vehicles. In the very beginning those tubes were just rubber. The average engine temperature of the average engine was between 130-160 degrees, well below the boiling point.

Cooling system pressures are about 16psi, and as these hoses started to deteriorate, it was very obvious. They would swell and balloon out, or they would get very soft, like squeezing a bar of butter that has been at room temperature for a couple of days. Alternator and power steering belts were what is called a “V” shape design and as they broke down and lost their resiliency they would slip and howl letting not only the owner, but the entire neighborhood know that they were bad.

Now as technology has improved so have the compounds that these belts and hoses are made of and their design has changed significantly. “V” shaped belts have evolved to ribbed belts or serpentine belts as they are most commonly referred as. Timing belts have become notched or cog driven but do not mix them up as they are far from the same even though they look alike. Under hood temperatures are well into the 200 degree range and the construction of the coolant hoses have been reinforced to withstand the heat.

They have also become preformed with intricate bends and turns so that they fit as designed. Lost is the day of the universal flex hose that many of us grew up with. Many radiator hoses are pre-formed with two or more other hoses permanently molded into what now looks like Medusa’s hair when held in your hand.

Power steering hoses are now handling thousands of pounds of pressure, as air conditioning hoses must handle pressures upwards of 450 pounds. Brake hoses must be able to handle between 800 and 1500 pounds of pressure PLUS heat ranges close to 600 degrees Fahrenheit and all of the road grime, salt and debris that is on every road in this country.

So what does this mean to all of you? First of all it means that due the improvements in the automotive section of these rubber companies that you will very rarely see those soft and swollen hoses under your hood. It means that now you must rely on common sense and the expertise of your service provider to know when these components need to be serviced.

As a rule most serpentine belts will develop cracks in the ribs, known as checking, at around 40,000 miles. Sometimes they will squeal on heavy acceleration or in wet weather. Because most of these belts have 6 ribs they are very forgiving and can go a long time without giving you any indication of their failure. However lose a belt while on the highway and you will lose your cooling system, power steering and charging system simultaneously. If your braking system is run by your power steering pump you will lose your braking properties also.

Pop a hose and you run the danger of overheating your engine also. These newer aluminum block engines do not take kindly to overheating and usually end up with major engine damage. Break a timing belt on any of these newer model vehicles and be prepared to do major engine work well into the thousands of dollars.

Here is the best advice that I can leave you with. Check your serpentine belts at 40,000 miles, make plans to change your coolant hoses at around 70,000 miles or at 7 years. Most timing belts should be replaced between 60,000 and 95,000 miles or after 7 years regardless of the mileage. This is all in your owner’s manuals or on line. S.W. Florida is considered a severe driving location so remember that figures lie and liars figure. Being proactive saves you money in the long run, and PREVENTIVE MAINTENANCE REDUCES THE COST OF OWNERSHIP.


Gregg’s Automotive Maintenance & Repair Center

236 S. Tamiami Tr.
Punta Gorda, Fl. 33950
Auto Repair, A/C Repair, Oil Change, Brake Repair & Transmission Services