Driving a manual transmission can make you feel very macho. All you can think of is power as you shift those gears and go faster. However, that clutch can only take so much. Your hot rod may be letting you know that the clutch needs attention. If that’s you, read on to find out if there is a problem with your clutch and what you can do to get back in the race.
What is a Clutch?
A clutch connects rotary shafts so that they can engage. and transfers the rotational power from the engine to the tires in cars with a manual transmission. The clutch consists of a flywheel and a clutch plate.
The clutch relies on frictional forces to engage and disengage the power transmission from the driving to driven shaft. The clutch fork helps the clutch engage and disengage the clutch. When your car comes to a stop , the connection between the engine and your tires must be broken to keep the engine running. If you’ve ever driven one, you know that it is the third pedal under the dash that must be pushed before you can change gears. If you don’t, a disengagement of the wheels will cause the engine to shut down.
There are different kinds of clutches, to include friction, cone, wet versus dry, centrifugal, and multiple plate clutches. The self-adjusting clutch (SAC) (view on Amazon) prolongs the service life of the clutch disc. As the clutch disc wears down, the clamp load remains consistent. The non-self-adjusting clutch (Non-SAC) have a shorter life cycle than SAC . The clamp load decreases as the disc thins.
Causes of a Bad or Worn Out Clutch
The clutch is worked every time you drive the manual transmission vehicle. Over time, the clutch wears out. It wears out really fast for people who drive hard. Of course, other things can go wrong that affect the performance. In some cases, the friction has decreased affecting engagement and causing the clutch to slip. At other times, the clutch may stick.
Slipping Clutch
The clutch needs friction to engage. When the friction is lost, you may be pressing the gas , the car is only inching along. When we say the clutch is slipping, we mean that the clutch is engaging and disengaging with no power transfer to the tires. The problem starts in first gear when you try to accelerate. You are moving slowly, but it seems like the engine is racing. In any case, the slipping clutch can damage your drivetrain. Here are the most common causes of a slipping clutch:
Clutch linkage is damaged, bent, misaligned – This can happen when the cable housing is rusted. Keep in mind that a slipping clutch can go on for a long time before it finally gives out.
Improper dimensions – A very common cause of the slipping clutch is when the step and cup dimensions are inaccurate after the flywheel is resurfaced or machined.
Damaged motor mounts – Bad motor mounts can cause different types of trouble for the transmission and drivetrain. The motor mounts are supposed to keep the engine vibrations from causing problems. In the front wheel drive vehicles, the motor mounts support the engine and the transmission. The CV joint axles can disengage from the transmission differential. This is not the most common problem with the transmission; however, it could happen.
Damaged pressure plate – The pressure plate (view on Amazon) is controlled by a lever and springs. It is designed to place pressure on the clutch plate/disc to keep it against the flywheel. When the clutch is worn, the pressure plate is damaged. The slipping clutch causes damage to the pressure plate surface.
Clutch linkage damaged, bent, or misaligned – The clutch linkage consists of the clutch pedal, rods, arms, and cables. The hydraulic clutch has a master and slave cylinder, a reservoir, and a hydraulic line. There should be free play in the clutch linkage. If not it, may need to be adjusted.
You Treat Your Car Like Shit – If you fail to maintain your vehicle, it can lead to the clutch going bad and this isn’t something you want to experience. Failing to maintain your vehicle can lead to certain components going bad and this can cause knock-on effects with other components. If you want to prevent this from happening, you’ll need to make sure that you look after your vehicle.
If you want to avoid clutch problems or other issues and save $100s of dollars that you’ll spend at the auto repair shop, you’ll need to service your vehicle often – you can use our mechanic-rated Auto Maintenance and Repair Manual to do this. It’s basically what mechanics use to go through your vehicle to check if there are any problems that need fixing. As soon as they notice the most minor problem, they’ll ask you to fork out some money even though it’s a problem you can fix yourself in minutes – the manual will teach you how to maintain your vehicle every few thousand miles and it’ll teach you how to fix minor problems that mechanics will ask you to pay for; saving you money in the long run.
A lot of our readers have the Auto Maintenance and Repair Manual printed on their garage wall and 92% of them haven’t visited the auto repair shop in the last year because they know what to do to avoid problems. All it takes is giving your vehicle a little attention every few thousand miles and you’ll never spend money at the workshop again.
Sticking Clutch
When the clutch is not releasing as it should, it endlessly turns the input shaft. Your car will make a grinding sound, and you not be able to put it gear at all. Here are the common causes for a sticking clutch:
Damaged slave/master clutch cylinders – The slave cylinder works with the master cylinder to disengage the clutch. The slave cylinder gets pressure from the master cylinder and a rod is extended. When there are problems with the cylinders, it is difficult to change gears.
Broken clutch cable and cable adjuster – The clutch cable adjuster regulates the slack and the tension in the clutch cable. When the cable is broken or it is not adjusted properly, the clutch pedal will fail to engage the clutch disk. This can cause problems when engaging and disengaging.
Air in hydraulic line – When there is air in the hydraulic system, it causes problems. When you press the clutch pedal, the master cylinder forces the hydraulic fluid through the line to the slave cylinder. In the case that air is in the hydraulic, the clutch needs to be bled.
Mismatched clutch components – You may experience engagement problems when the components are mismatched. When you use a clutch kit, all of the parts are matched from the same supplier so you don’t have to worry about this problem.
Symptoms of a Bad or Worn Clutch
When the clutch is damaged or just worn out, it changes the driving experience. Here are the most common symptoms that the clutch is worn out or going bad:
Bumping and Grinding – Any odd or loud sounds coming from under the hood mean there is a problem that needs to be addressed. When the clutch pedal is depressed, you hear these bumping and grinding noises from the transmission. It also happens in neutral and when you release the clutch pedal. Several things can cause this to happen. For one, the input shaft is still spinning when you take your foot off the clutch pedal. This often happens when the shaft bearing is worn out and that the clutch disc is still engaged. It also happens when the clutch fork is malfunctioning. One problem here may be the lubricant has dried out. Some component, such as a rod, may be scraping in there. Or, there is a problem with the clutch fork.
Clutch pedal will not engage – The clutch pedal lets you know when there is a problem when it vibrates, chatters, and refuses to move. With this problem, you may constantly have to press down hard to engage the clutch or it will no longer engage at all. The clutch is not receiving the required force from the drive, so it does not depress or fully engage. The pedal linkage is binding or sticking which causes other problems. It could also be a sticking pivot ball, cable, or cross shaft. If the system is hydraulic, it could be worn seals.
Clutch pedal chatter – When the clutch chatters, or vibrates, it means that the clutch disc is losing hold on the flywheel. This is happening intermittently most likely because of a problem with the clutch disc lining. The lining could be burnt, glazed, worn out, or contaminated with oil. There could also be a warped or damaged flywheel or pressure plate, pressure plate diaphragm, or pilot bearing.
Clutch pedal stuck to the floor – When you press the clutch and release it, it should return to its original position. When the clutch pedal does not return, there are binding issues with either the release bearing or the linkage. The springs in the linkage could be overextended and must be adjusted. There could also be problems with the pedal stop or release bearing.
Clutch pedal soft or spongey – When the release bearing or clutch fork are damaged, the clutch pedal may feel spongey, soft, or loose. Oftentimes, the pressure plate diaphragm spring has failed. Many other things could have caused it, including problems with the master cylinder, a leaking hose or pipe, low fluid, and air in the hydraulic system.
Won’t go into gear – When this happens, it is most likely that you cannot go into third gear or reverse. This problem is most commonly associated with the linkage or a damaged clutch plate. In the hydraulic system, the problem may be the master or slave cylinder. In the mechanical system, this problem could be coming from the control cable, pressure plate, clutch disc, release bearing, or release lever.
Get Help with the Bad or Worn Clutch
Once the clutch is worn or damaged, it must be repaired as soon as possible. There are a few steps you can take to get help:
Use the OBD2 Scanner – The OBD2 Scanner (view on Amazon), along with your owner’s manual. These tools provide trouble codes for things that go wrong under your hood. Several OBD2 codes pertain to the transmission and the clutch. When certain components in your vehicle fail, the engine management system makes a record of the event. Often, the OBD2 delivers a trouble code, which triggers the Check Engine Light (CEL) on your dash. Here are some examples of the type of error codes you may see for the clutch:
You may see the P0830 “Clutch Pedal Position (CPP) Switch A-Circuit Malfunction” and the P0903 “Clutch Actuator Circuit High” trouble codes which are associated with problems in the transmission. The clutch pedal position switch is damaged for P0803. There could be damaged or burnt wiring involved with this problem. Also, the clutch actuator in manual transmissions have several parts that may be malfunctioning. With the P0903 code, it could be the pedal, the slave or master cylinders, or the clutch pipe.
Bleed the clutch – Air in the hydraulic system is no good. Bleeding the clutch, it causes problems. When you press the clutch pedal, the master cylinder forces the hydraulic fluid through the line to the slave cylinder. Bleeding the clutch means removing that air from the hydraulic. To remove the air, use a vacuum pump to push or pull the air through the fluid line to the bleeder valve located on the slave cylinder. Use a clear tube so you can actually see when the air is gone.
Maintenance Inspections – If you don’t have a scanner, your local automotive professional has one. You can make sure that your clutch is working properly by having regular maintenance checks performed on your car. Many automotive tools are now computerized, making it easier to find problems under the hood.
Get Moving
Now you know all that there is to know about the clutch in a manual transmission system. It’s time to get a move on. Remember, safety first. If the clutch is wearing out or gone bad, don’t try to drive the car. Get the repairs so that you can get back on the road.