Saturday, 4 April 2015

How To replace clutch

Clutch Replacement

How to Replace a Clutch
To replace a clutch disc thetransmission must be removed. A clutch is a requirement on any vehicle with a manual transmission. Its purpose is to disengage the engine from the transmission to shift gears and while the vehicle needs to stop and remain in gear. The vehicle’s clutch will last for thousands of miles, but they do wear out and need replaced. Common symptoms of a worn clutchis a chattering when first pulling out, slipping, and gear grinding when shifting. Replacing a clutch is a big job, but with the right tools and some time, you can do it yourself saving hundreds of dollars in labor. CAUTION: Transmissions are heavy. A transmission jack should be used to hold the transmission’s weight and help you slowly remove it from the vehicle. Make sure to disconnect the negative battery cable before starting this repair.
Park your car on level ground with the engine off and the emergency brake off. Block both sides of the front wheels. Always raise a car according to the manufacturers recommended instructions and secure with jack stands. Also, we will be dealing with gear oil and grease so be sure to wear protective clothing, eyewear and gloves.
Tools and Supplies Needed to Complete this Job
1. Hydraulic floor jack
2. Quality jack stands
3. Transmission jack
4. Wrench set
5. Pry bar
6. Socket set with extensions
7. Screwdriver set
8. Fluid catch pan
9. Clutch alignment tool (included in most new clutch replacement kits)
10. Electrical tape
11. Shop towels

12. Clutch replacement kit including: disc, pressure plate, throw out bearing and pilot bearing (if equipped)
13. Gear oil/transmission fluid
14. Pilot bearing removal tool - If equipped
Remove Transmission Directions
Step 1 - Disconnect the battery(negative side)
Step 2 - You will need to lift the rear (RWD) or front (FWD) of the vehicle. Therefore, make sure the vehicle is on a firm, flat surface. Engage the parking brake and block the wheels so the vehicle can‘t move.
Step 3 - Using a hydraulic jack, lift the vehicle one side at a time and place a quality jack stand under the frame or manufacturer’s recommended location to support the vehicle. Do this to both sides so you have plenty of clearance to work under the vehicle.
Step 4 - Drain the transmission of fluid
Step 5 - Remove any obstructions such as exhaust and heat shielding
Step 6 - Next, you will need to remove the vehicle’s drive shaft or axles. On the rear of the drive shaft is a universal joint (u-joint). It is held to the differential with U-bolts or regular bolts. Remove the U-bolts/bolts and pushing forward on the drive shaft, slip the u-joint away from the differential. You may need a pry bar to separate the joint from the differential. Make sure not to allow the drive shaft to drop to the ground. The end caps on the u-joint can come off. There are needle bearings inside them that can come out. Therefore, we recommend wrapping electrical tape around the u-joint to hold the end caps in place.
Step 7 - Then, place a drip pan under the tail housing of the transmission and carefully slid the front yoke from the transmission housing and remove the drive shaft. A small amount of transmission fluid may drip out.
Step 8 - Remove starter assembly (if needed)
Step 9 - Now, based on the model year of the vehicle, inspect the transmission. Remove any wiring harnesses, vacuum hoses, or other items that are attached to the transmission. We recommend marking everything you remove so you remember where it came from when you reinstall the items. Masking tape and a marker will make things easy to locate.
Step 10 - Next, you will need to remove the starter. Remove the wiring from the starter and the two bolts mounting it to the transmission.
Step 11 - Secure the engine by placing a jack under the oil pan. NOTE: To avoid damage to the oil pan, make sure to place a 2x4 between the jack and the oil pan to distribute weight and not dent or damage the oil pan. If the oil pan is made with aluminum, be extra careful not to crack it.
Step 12 - Now that everything is removed from the transmission and the engine is secured place a transmission jack under the transmission and slightly lift up on it to remove pressure from it.
Step 13 - Remove the transmission mount from the cross member and remove the cross member if clearance is needed.
Step 14 - Next, remove the bolts that attach the transmission bell housing to the engine.
Step 15 - Once the bolts are removed, carefully move the transmission away from the engine until the input shift clears the pressure plate.
Step 16 - Next, remove the bolts holding the pressure plate to the flywheel and remove both the pressure plate and the clutch disc.
Step 17 - Now you can remove the transmission. While it is out, closely inspect the flywheel for scoring, heat spots, cracks, or anything out of the ordinary. Any damage justifies having the flywheel machined or replaced. NOTE: Machining the flywheel will not eliminate heat spots. Replacing the flywheel maybe required. This is also a good time to check the rear main seal on the engine for leaks and repair as necessary.
Step 18 - Inspect the pilot bearing at the center of the flywheel to remove this you may need a pilot bearing removal tool.
Step 19 - When re-installing the transmission never allow the transmission to hang without the mounting bolts. If the transmission is allowed to hang it can bend the clutch disc causing the clutch not to disengage.
Step 20 - Finish reassembly and refill the transmission
Step 21 - Adjust as needed (note: some cars have self adjusting clutched so readjustment is not required)
Clutch Replacement (once transmission is removed)
Step 1 - If the flywheel was removed, make sure to properly clean the crankshaft flange that it bolts to. When tightening the flywheel, do it in a star sequence to the manufacturer’s recommended torque.
Step 2 - Install the new clutch disc and pressure plate. Tighten the pressure plate to the manufacturer’s recommendation. (Note: The clutch disc can only be installed one way, if the disc is installed incorrectly the clutch will not operate. In most cases the replacement disc will have a sticker that says " flywheel side" if not take note on how the old disc was installed). Reinstall clutch using a clutch disc alignment tool to center the clutch disc while the clutch assembly is hand tight.
Step 3 - Install the release bearing with a thin layer of grease on the bearing sliding surface.
Step 4 - With the transmission jack, slide the transmission back into position.
Step 5 - Carefully, move the transmission forward until the input shaft enters the clutch disc’s splined opening (center). (Note: Do Not force the shaft. It should be aligned so that is glides into place. In most cases, you will need to use a clutch alignment tool.
Step 6 - Once aligned and the transmission and engine are back together, replace the bell housing bolts and any items you removed from the transmission. Tighten the pressure plat evenly to avoid bending

Troubleshooting Noise and Problems
  • If the vehicle is running and a whirring sound is heard and then it goes away when the clutch is depressed, the transmission input shaft bearing has failed.
  • If the transmission is quiet in neutral but when you depress the clutch asquealing noise is observed, a clutch throw out bearing has failed
Tip 1: Never allow little noises go unattended; a small noise can cause a large problem and transmission operation failure. Never overload a vehicle or tow beyond the capacity this can cause premature transmission failure.

Tip 2: Cars with automatic transmissions are equipped with a torque converter that when it fails will cause the engine to stall, but only when you put into forward or reverse gear.

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