Auto Repair Basics

The Manual Transmission – The Clutch

Otis The Auto Guy — Wed, 16 May 2012 15:19:52 +0000

The clutch assembly on a car with a manual transmission is located between the engine and the transmission and serves as a means to disconnect the transmission from the engine. If the car had no clutch the transmission would always be turning at the same speed as the engine and the engine would stall when the car came to a stop.

The clutch assembly consists of three basic parts; the flywheel, the pressure plate and the clutch disc. The flywheel is part of the engine and is the driving member of the clutch assembly. The pressure plate is attached to the flywheel and uses spring pressure to hold the clutch disc against the flywheel. The clutch disc is attached to the transmission and transmits the rotary montion of the engine to the transmission and ultimately the wheels. The clutch disc is held in firm contact with the flywheel by springs in the pressure plate. Depressing the clutch pedal operates a linkage that releases the pressure holding the clutch to the flywheel and allows them to rotate freely of each other. The linkage connecting the clutch pedal to the clutch can be either mechanical or hydraulic.

Slipping:

The clutch disc has friction material on both sides. The friction material is similar to that used for brake linings. When to friction material is worn the result is slipping. Slipping can also be caused by friction material that is soaked with oil, a warped pressure plate or by weak springs. To check for slipping park the car, apply the the parking brake and disengage the clutch. Shift the transmission into third gear, rev the engine. Release the clutch pedal slowly until the clutch engages. If the engine does not stall within a few seconds, this is a sign of slipping.

Chatter

Chatter is shaking or shuddering that is felt when the clutch is engaged. Chattering is evident while the clutch is being engaged and stops when the clutch is fully engaged. Clutch chatter is usually caused by contamination of the clutch disc friction surfaces. Contamination can be caused by oil or hydraulic fluid leaking onto the clutch disc. Chatter can also be caused by loose bell housing bolts, broken engine mounts, and a damaged clutch linkage. You can check for clutch chatter by starting the engine, depressing the clutch completely, and shifting the transmission into first gear. Rev the engine and then slowly release the clutch pedal to check for chatter as soon as the pedal begins to engage. Do not release the pedal completely, and, depress the clutch pedal immediately and reduce engine speed or you could damage the clutch parts.

Drag

Clutch drag is when the clutch disc is not completely released when the clutch pedal is fully depressed. To check for clutch drag; with the engine running depress the clutch pedal completely, and shift the transmission into first gear. Without releasing the clutch shift the transmission into neutral, wait 5 seconds and attempt to shift smoothly into reverse. If shifting into reverse after waitng 5 seconds causes grinding of gears clutch drag is a possible culprit.

This is not an exhaustive list of clutch problems but only the most common ones. All sorts of noises and vibrations can be caused by clutch problems. Also, some cars such as the Kia Forte are prone to have clutch problems. If you suspect that you have clutch problems bring your car to Hi-Tech Car Care and we will give it a check up.

No matter what problem you are having with your car, you can be sure that we will fix it right at Hi-Tech Car Care. We have the equipment and expertise to diagnose and repair any problem.

Identifying The Brake Problem

Otis The Auto Guy — Wed, 21 Mar 2012 17:30:42 +0000

Excessive Effort
If you have power brakes and while driving stopping seems to take excessive effort, you probably need to have the power booster replaced.

Too Long To Stop
If your vehicle travels too far before coming to a stop you either need to have you brakes your brakes adjusted or you need new brake linings.

Pedal Too Low
If you have power brakes, the pedal should stop 1 to 1-1/2 inches from the floor. On cars without power brakes, the pedal should stop 3 or more inches from the floor. If pumping the brake pedal a couple of times causes the pedal to rise you either need to have your brakes adjusted or you need more brake fluid.

Pulls To One Side
If your vehicle pulls to one side when you apply the brakes, the problem could be a stuck caliper or a brake fluid leak. Bring it to Hi-Tech Car Care And we will diagnose your problem and fix it.

Sinking Pedal
This is an indication that your master cylinder may be defective, and that its unsafe. The master cylinder needs to be repaired or replaced

Pulsating Pedal
If your brake pedal pulsates up and down when you stop in a non-emergency situation it is usually caused by a warped disc or drum. This is caused by your brakes being overheated from overuse. The warped disc or drum needs to be either machined or replaced.

Spongy Feel
This is an indication that you have air in your brake lines. The brake system needs to be bled in order to purge the air from the system.

Shaking Steering Wheel
If your steering wheel shakes when you brake your front brake discs need to be machined or replaced.

Squealing
If your brakes squeal when you stop the cause can be out of round drums or discs, worn brake linings the, loose or worn parts, or inferior brake linings.

Grinding
A grinding noise coming from your brakes indicates excessively worn brake linings which can cause extensive damage to your brake system. Do not drive your vehicle, have it towed to Hi-Tech Car Care.

No matter what problem you are having with your car, you can be sure that we will fix it right at Hi-Tech Car Care. We have the equipment and expertise to work on discontinued lines such as Saturn and Oldsmobile. To avoid a master brake failure in the S Series Saturn, have regular inspections on the brakes with wheel rotations. Be sure to have your brake pads replaced as necessary in the Kia Sedona to avoid crystalized rotors. We can also replace your Pontiac G6 front Rotors, if you hear brake noises before the rotors warp.

Good to know when fixing your vehicle brakes

Otis The Auto Guy — Mon, 23 May 2011 20:40:41 +0000

Like most car parts, brakes wear out. It is hard to define how long brake life is because it depends on how they are driven. Brake pads can last about 30,000 to 70,000 miles. They usually let you know they are going bad when they start to squeal. But they do not always do that. It is a good idea to get them checked periodically. A good time is when you rotate your tires. If your mechanic does not suggest checking your brakes, remind him/her. We at Hi-Tech Car Care will suggest it to you.

Most cars today are equipped with drum brakes, disc brakes or a combination of the two. The majority of cars have disc brakes on the front wheels and drum brakes on the rear wheels.

Drum Brakes

Drum brakes consist of an outer shell which is attached to the wheel and rotates with it. Inside the drum are a pair of brake shoes which are pressed into the inside of the drum by hydraulic pressure when the brake pedal is depressed. The brake shoes are curved to match the inside of the drum and ride in close proximity to the drum without touching it. The brake shoes are kept from touching the drum by a set of springs and the distance between the drum and shoes is controlled by an adjusting mechanism. In use the brake shoes gradually wear down and the distance between the drum and the shoes must be adjusted. In older cars the brakes needed to be periodically adjusted by hand but modern cars have automatic adjusting mechanisms which operate either when the car backs up or when the emergency brake is applied. Eventually The brake shoes will wear down to the point where they have to be replaced; this is the most common type of service required for drum brakes. If the brake shoes are allowed to wear down too far they can score the inside surface of the drum. When this happens the brake drum must be either refinished or replaced.

Disc brakes

The operating principle behind disc brakes is similar to drum brakes but they are easier to service. Disc brakes consist of a rotating disc which is attached to the wheel. A caliper is mounted at the edge of the disc which carries one or more pistons which act on pads in contact with the disc. When the brake pedal is depressed, hydraulic forces squeeze the disc between the pads. There are no springs to retract the brake pads and they are in constant light contact with the disc. There is no need to adjust disc brakes since the pads do not fully retract when the brake pedal is released. Similarly to drum brakes; the pads need to be changed when they become worn and this is the most common service performed on disc brakes. If the brake pads are allowed to wear down too far they can score the surface of the disc. When this happens the disc must be either refinished or replaced.

Emergency Brake

The emergency brake should more correctly be called the parking brake. The emergency brake should not be used for stopping unless it is absolutely necessary. In modern cars the emergency brake operates on the rear wheels using a mechanical linkage instead of the hydraulic actuation used by the main braking system. The mechanical linkage consists of a cable inside a carrier. The emergency brake should be operated occasionally to make sure that the cable has not siezed inside the carrier.

Service

The brake system should be inspected for leaks at each oil change and the brake pads, shoes, rotors, drums, brake lines & hoses and parking brake system should be inspected at each tire rotation.

Car Noise, what not to do:

Otis The Auto Guy — Mon, 14 Mar 2011 20:48:48 +0000

When one says: “My car sounds funny” we know you are not saying funny “ha-ha” it is funny peculiar.

When you are attentive to your vehicle, you notice it talks to you. It could be your brake, belt, a bearing… who knows? Hi-Tech does.

The initial assessment of a vehicle noise is typically free at Hi-Tech Car Care.

However, there are times your mechanic has to be a technician.

Hi-Tech Car Care has some of the best and brightest technicians in the valley.

They have cool, sophisticated, hi-tech equipment – They are equipped to find any noise.

And once it is found we know how to fix it.