Monthly Archives: June 2024

It’s Brake Time (Brake Calipers)

Race car drivers have demonstrated the advantages of disc brakes, so most modern vehicles use them.  Sometimes just the front wheels have disc brakes, but many vehicles now have them all the way around. 

A major component of the disc brake is called a caliper.  It works by squeezing brake pads against the disc or rotor, kind of like a bicycle hand brake.  The brake pads themselves are what contact the rotor, causing friction to build and the wheel to slow down, but it’s the calipers that apply the pressure to the pads.

Caliper design has evolved over the years, and there are two common types.  One is called a floating caliper.  It has one or two pistons on one side of the disc. When you push down the brake pedal, the piston or pistons in your caliper put pressure on that one side.  A mechanism connected on the other side of the disc applies pressure as well, squeezing your disc so the vehicle stops.  Floating calipers are less expensive since they have fewer parts.

The other type is called a fixed caliper.  They use pistons on both sides of the disc, sometimes several.  They are often used in more high-performance or heavy-duty vehicles.

Calipers can have rubber seals to keep out dirt, debris and moisture, but when that rubber wears out, sometimes the calipers can get contaminated.  They can stick or start leaking; they can even rust.  Then your caliper can get stuck applying that “squeeze” when you are not pressing on the brake pedal.  Or they can get stuck in the other position, not applying stopping power when you press the pedal.

When this happens, it’s not unusual to feel your vehicle pull to one side when you brake.  You might notice a burning smell from the constant friction if the caliper is stuck on, plus you may feel the heat from the wheel after you park and get out of your vehicle.  Sometimes you’ll hear a high-pitched sound or clunk if your calipers are binding up. 

That’s your cue to have them checked out at your vehicle service center.  If your calipers aren’t working correctly, it can be a safety hazard.  Sticking calipers can affect your ability to steer and stop; this is the kind of “brake time” you need so you can get them back on track and working properly.

Autotronics of St. Peter
111 Jefferson Avenue
St. Peter, MN 56082
507.934.9290
http://autotronicsstpeter.com

Oil’s Well That Ends Well (Oil Change Grades and Weight)

Changing your oil regularly is one of the most important things you can do to keep your vehicle running well.  And knowing the right type of oil to use is also very important. 

Engine oil is classified by weight, but it doesn’t refer to how much the oil would weigh if you put it on a scale.  It refers to viscosity, or how easily the oil flows through the engine.  Most engines operate normally at around 210°F/99°C.  The viscosity, or weight, is assigned a number by how well it flows at that temperature.  The lower the number, the more freely it flows. 

Most vehicle engines use what’s called a multigrade oil which behaves differently in different temperatures. Multigrade oils have a “W” in their viscosity number that you may have seen on a bottle of oil, something like 5W30.  The W stands for winter and shows how freely it flows in colder temperatures.

That means a 5W30 oil will behave like a 5 weight oil in lower temperatures (less viscous or thinner) and a 30 weight oil in warmer temperatures (more viscous or thicker).  That’s important on a cold day because the oil needs to behave like a thinner oil when you start your engine since it need to lubricate engine components immediately to protect the metal components. Then as the engine warms up, it behaves like a thicker oil to prevent friction among those parts.  Pretty neat trick, right?

The type of oil you use can differ depending on what type of climate you operate your vehicle in and how your vehicle is used (carrying big loads, towing, etc.). Your owner’s manual contains several different recommendations based on these factors.  Your service advisor can recommend the right oil for your needs.  Like Shakespeare said, “Oil’s well that ends well.”

Autotronics of St. Peter
111 Jefferson Avenue
St. Peter, MN 56082
507.934.9290
http://autotronicsstpeter.com

Cool Running (Water Pump)

Your vehicle is like you in a way.  When it gets hot, it needs to be cooled down.  And one of the key parts to keeping it cool is the water pump.

Now, that’s a bit of a misnomer.  It IS a pump, but it’s pumping coolant, not pure water.  Cooling off your engine is vital since it builds up heat when it creates power by burning fuel.  Your water pump acts as a way to recirculate that coolant.  It goes through a series of tubes and hoses through the engine where it picks up heat, then is sent off to the radiator to get rid of that heat.  Cooled off, the coolant is recycled through the water pump to start the journey again.

The water pump works by taking mechanical power from the engine, usually from a belt.  Obviously, that belt has to be in good condition and adjusted properly or else the water pump won’t be able to do its job.

Here are some things to look for that will signal problems with your water pump.  If your heat gauge is erratic or showing a much higher than normal temperature, that could be a sign of trouble.  Another is if you hear a whine under the hood.  And if that gets louder when you go faster, get it checked right away.  You may see steam coming out from under the hood or coolant may be leaking. 

These signs signal that it’s time for you to have a technician check to see where the problem is. Some water pumps are powered by a timing belt.  If your vehicle has that design and your timing belt is due for replacement, sometimes it’s a good idea to replace the water pump too, even if it’s working properly.  That’s because the labor to replace the timing belt can be expensive and it may be wise to proactively take care of the water pump while it’s disassembled.

Your service advisor will explain the options available and offer the best path to keeping your water pump doing its job.  Your engine’s life depends on it.

Autotronics of St. Peter
111 Jefferson Avenue
St. Peter, MN 56082
507.934.9290
http://autotronicsstpeter.com