HOW TO CHECK TIMING BELT @ HOW TO REPLACE A TIMING BELT.
Today we would like to share some good information for all readers.Maybe this can be a guide for you on how to take care your car’s timing belt.It is really easy for you to check your timing belt but it will be difficult for you to change it on your own.If you think that it is complicated, it is better for you to just send your car to the workshop or service centre.Not all of us a mechanical person right.So, let’s read this information.
HOW TO CHECK TIMING BELT
Many cars have accessory belts or timing belt that drive the alternator, the power-steering pump, the air conditioning compressor, the water pump in many cases, and other parts of a modern vehicle. Newer cars have a Serpentine multi-accessory drive belt, as shown here.
A Serpentine multi accessory drive belt.
Typical V6 Timing Belt - Timing belts last 100,000 to 150,000 km. **Check your owner’s manual for the manufacturer’s replacement interval.
If you drive an older car, you have to check the separate belts, as shown here. – Like the Perodua Kancil engine.
If you can’t get to an accessory belt easily to check it yourself, have it checked when you have the vehicle serviced or if the belt gets noisy or any of the equipment it drives begins to malfunction.
It isn’t easy to figure out whether a belt is at the right tension just by looking at it, and often it’s obscured by a shield or cowling. If the belt is loose, you’ll hear squeaky noises when you accelerate sharply. With the hood up, the gearshift in Park or Neutral, and the parking brake on, have a friend accelerate the engine while you listen. Be sure to keep your hair and clothing away from the belt.
Because tensioners are spring-loaded, they can be unsafe to deal with yourself. Check your owner’s manual or a service manual for your vehicle’s make, model, and year to see what’s involved in adjusting your accessory belt. If you can’t reach the adjusting mechanism without removing other parts, if adjusting the belt requires special tools, or if it looks as though releasing the tension may be risky, you should have a professional deal with it.
If you can see an accessory belt easily, here’s what to look for:
– If the belt “gives” more than 1/2 inch when you press on it but otherwise is in good condition, it may just need to be adjusted.
– If the belt is glazed or has oil on it, the slick surface will slip where it winds around the pulleys and it won’t be able to efficiently drive the components connected to it. Your engine may overheat because the water pump isn’t operating properly, or the air conditioner may fail to cool the interior of your vehicle. Have the belt replaced.
– If you see chunks missing from the belt or many cracks across its surface, or if it’s frayed or tearing, debris may be embedded in it, or one of the pulleys may be out of alignment. The safest move is to replace the belt.
If the belt squeaks, it may have been contaminated by water, coolant, oil, or another fluid. If it’s just water, check around the water pump and the hoses to see where the leak is, and eliminate the cause of the leak. The water will dry up on its own. The belt needs to be replaced if the contaminant is coolant, oil, power-steering fluid, or some other substance or if the belt has broken, is frayed, or has large cracks or pieces missing.
HOW TO REPLACE A TIMING BELT.
The timing belt (or chain) is the sole component that keeps the camshaft (make that camshafts on a DOHC or V-type OHC engine) and crankshaft in sync. So replacing this cogged reinforced-rubber belt at regular intervals generally every 100,000 km unless the car manufacturer specifies longer.It is a lot less expensive and aggravating than having it break first.
Usually on most transverse four-cylinder engines, you’ll have to remove the driver-side motor mount in order to gain access to the timing belt. This means the entire powertrain needs to be supported in that area while you’re working. And finally, getting to the lower portion of multipiece timing belt covers usually requires underbody access. A fender cover doesn’t hurt either, to protect the paint from your belt buckle and dropped tools.
(1) Remove any shrouding in the wheel well so you can access the crankshaft snout and the lower timing belt pulley.
(2a) Find the timing marks on the flywheel and cam, and set them both to TDC.
(2b) The flywheel pulley TDC mark is accessible through a hole in the bellhousing.
(2c) The camshaft TDC is easy to find — especially if you add white paint.
Be careful! Make sure you know where the timing marks are on your engine, and that you have them set up properly with No. 1 cylinder at top dead center (TDC) on the compression stroke before attempting to replace the timing belt.
1) That interference engine thing again.
2) Every camshaft and crankshaft on planet Earth is indexed to No. 1 TDC.
If you try to remove and replace the timing belt with the engine in any other position, chances are good you’ll throw things out of time. Then you’ll get confused and have to pull off the valve cover as you try to determine when No. 1′s valves are closed (which begins the compression stroke) in order to re-index the engine. Get your marks lined up right the first time.
After you remove the top section of the timing belt cover, you should see a timing mark on the camshaft sprocket. This mark usually lines up with the edge of the cylinder head or valve cover. For the crankshaft below, there probably will be a timing mark on the damper pulley that lines up with another mark on the lower cover. Or, the service manual may direct you to the transmission end of the engine to look through a hole in the bellhousing for a timing mark on the flywheel. The flywheel is bolted to the other (transmission) end of the crankshaft. On some vehicles, you may find these marks in all three places.
(3) Support the engine with some sort of skyhook if you need to remove the rightside motor mount. Some belts are installed with a mount in their center, making changing them problematic.
(4) The motor mount can now be removed temporarily.
(5) Release any belt tension by freeing up the belt tensioner pulley.
Of course, there are professional engine-support rigs available for purchase or rent. But as you can see in these photos, some lumber and an adjustable tiedown strap work just fine to support the powertrain while you remove that cumbersome motor mount. Once it’s out of the way, though, you’re almost home. Just remove the rest of the timing belt cover sections and turn your attention to the tensioner pulley mechanism.
This tensioner may be an automatic hydraulic type that you simply crank in one direction to remove the old timing belt. Or, you may have to loosen the tensioner pulley adjustment bolt to release the tension and the belt. Before proceeding, confirm which way the engine rotates during normal operation. (Pull the fuel pump relay or fuse first if you need to disconnect fuel lines.) Knowing which way the engine turns is important for checking the new belt’s alignment later; you don’t want to be off by a tooth on one of the sprockets. The easiest way is to have a helper bump over the starter motor with the ignition key while you watch the engine. Of course, now you’ll have to reset your timing marks by hand. Don’t rotate the engine backward to the marks. Crank it around forward to maintain the correct tension and to keep the belt from jumping teeth.
TDC? Now you can carefully slide the old timing belt off its sprockets and pulleys, while trying to keep the camshaft and crankshaft from spinning. With all the timing marks lined up, route the new belt around the largest diameters first, leaving the smallest pulley or sprocket for last. It’s tricky to slip the new, stiffer belt over that last one, but you’ll get it after a couple of different wiggling, jiggling attempts. Now, make sure the timing marks are still lined up.
Warning: If you know you’re working on an interference engine, do not rotate the camshaft or the crankshaft independently while the timing belt is off the engine. You could cause the pistons to hit the valves, or vice versa, and cause the same damage as if the timing belt had snapped with the engine running.It will cause you a bent valves!
If you’re working with a manual tensioner pulley setup, now is when you perform the factory procedure to tighten the new belt. A hydraulic tensioner takes care of this for you. Once the tension’s set, place a socket on the big nut holding the front pulley on and use it to turn the engine over — two complete crankshaft revolutions in the direction of normal rotation. Line up all the timing marks again. Everything still on the money? Then you’ve finished replacing the timing belt.But you have another hour’s work to reinstall the cam belt covers, any shrouding, and all the wires, engine accessories and hoses you moved or removed.
(5) Release any belt tension by freeing up the belt tensioner pulley.
(6) Slip the new belt into place without disturbing the cam or crank pulleys, or the engine will be out of time. Check by slowly rotating the crank two full turns with a socket on the crank snout.