How Timing Belt Replacement Works

Attaching New Timing Belts

If you're replacing your belt as part of routine vehicle maintenance, then chances are your old belt -- the one you've successfully removed -- kept your engine in time for several years. To do that belt justice and keep your vehicle going strong, people embarking on their own auto maintenance need to take care when attaching new timing belts.

In fact, if Dan Trottier, an automotive technician with Bob's Auto Service Inc. in Saco, Maine, has any advice for timing belt replacement it's to take your time. He says, "Just take your time and you can do it. Don't feel you have to move quickly. Move at your own pace."

Although your technical manual will provide instructions for your car maintenance needs, the basic steps of attaching a belt during this automotive maintenance procedure are to:

  1. Again, make sure the engine is set to top dead center, which will make confirmation of the timing marks easier.
  2. Install a new timing belt and tensioner, making sure to properly align the timing marks as you do so.
  3. Adjust the tension of the new belt.
  4. Confirm all timing marks are lined up.
  5. Put everything back together, following the reverse of the steps in the previous section.

From these steps, the most important ones and those that deserve further discussion are the adjusting of tension and lining up of the timing marks. Just like a bandage that can cut off circulation if it's too tight or not provide enough protection if it's too loose, there's a middle road to take with tension. A belt that is on too tight will not last as long; a belt that is on too loose may skip or jump and fail to keep proper time. This makes your car less efficient and creates the possibility that your pistons and valves will collide. Always refer to your technical manual for exact tension specifications.

Once you have the tension right, you need to confirm all your timing marks are lined up. Lining up your timing marks is similar to setting your watch. If you don't set your watch right, you may be late or early. If you don't set your timing belt correctly, being late or early means your engine won't run efficiently and you run the risk of damaging your engine. Your automobile will have specific timing marks to set. Pay attention to your technical manual when confirming your marks are lined up. Then, proceed with reassembly.

Once you have everything under your hood back together, your new belt is set for its role as drum major of your car. You can take to the field for your halftime show -- or the open highway -- knowing you've enhanced your chances that all the players in your engine will remain on tempo.

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