How to Change the Timing Belt on a 2.0L, 4 Cylinder Mazda 626 1993 to

Step-by-Step Guide

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   Step 1: Obtain a manual and confirm that it has torquing instructions for bolts.

   Compare the instructions in the book to this article and follow any recommendations about removal, installation/replacement, pictures and diagrams that may be helpful.
   
   The OEM (original equipment manufacturers) repair manuals do not explain in detail for the inexperienced and may advise use of unnecessary tools or ignore explanation of basic techniques as it is written for an audience of Mazda mechanics.
   
   The tools needed in this repair will be mentioned in each step.
   
   Caution:
   When reassembling parts and torquing bolts to complete the installation, always use the "smallest workable ratchet, break-over wrench and/or cheater (leverage extension)" correctly to not over-tighten (over-torque) bolts.
   
   Over-tightening will break off a bolt-head, requiring much extra labor (more detail in the Warnings section).
   
   You actually might have to remove the engine to extract a broken bolt.
   
   Be cautious to avoid exceeding the torquing specifications
   - the cost of a broken off bolt-head and even falling into a cylinder is very high. , Put on the parking brake. ,:
   Change the timing belt, timing belt tensioner and its idler pulley.
   
   The diagram shows the following numbered parts: (1) retaining bolt for the harmonic pulley, (2) a large thin washer (the guard for the crankshaft opening) found behind the harmonic pulley (harmonic pulley not shown), (3) both halves of the timing covers, the belt (sort of tee-shaped, not numbered), and (4) the tube for the oil-dipstick (its retained by top left bolt of upper-half, timing-cover).
   
   Caution: this is an interference engine meaning that the valves and pistons will come into contact, interfere and may damage the engine in case (if) the timing belt were to break or slip on cam(s) sprockets or the crankshaft sprocket (more detail in the "Warnings Section"). ,,,, You will need to loosen the lock bolts a turn or more and then loosen the tensioner a good number of turns until you can get enough slack to remove the belts. , This will help get some working space, where it is difficult to loosen and tighten the lock bolt on the power steering tensioner with a combination wrench (14mm) even by switching ends of the wrench.
   
   Do not pry belts off or on. , Loosen the tensioner enough to remove the belt.
   
   The older models have two flat belts (not v-belts) and newer models probably have a single serpentine belt.
   
   Do not pry or force the belts to get them off. loosen the adjustment bolts more than you expect
   - new belts will be much tighter than broken in ones.
   
   By prying off belts, you risk damage to various parts with no saved time or effort. ,
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   Step 2: Work on level ground and block the wheels (so they won't roll) with bricks or wooden pieces about the size of a bricks.

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   Step 3: Avoid engine damage from the timing belt breaking or slipping

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   Step 4: or the tensioner pulley or idler pulley locking up (seizing) or the timing belt skipping one or more cogs on a sprocket causing valve timing problems and possibly breaking valves

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   Step 5: pistons and/or the engine cylinder (block).How?

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   Step 6: Understand the numbering of the cylinders and label the spark plug cables and cylinders 1

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   Step 7: 4 from left to right but the other end is not that easy and carefully pry and get the cables off their spark plugs.

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   Step 8: Check your manual for firing order which will be 1

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   Step 9: 2 or such for 1993--1997 (verify this carefully) and 1

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    Step 10: 2 or such for 1998 and after for how they plug onto the coil pack or distributor on older models.Caution: Disconnect the negative battery terminal so your engine can not be accidentally turned and so it can not be started in error

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    Step 11: also remove the spark plugs

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    Step 12: before doing dangerous work (their removal releases compression which makes the engine turn easily

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    Step 13: as well as work being safer).

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    Step 14: Drain all the coolant from the engine and keep it to use again or dispose of it legally

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    Step 15: no matter how little.

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    Step 16: Remove the accessory belt(s) for the alternator

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    Step 17: power steering

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    Step 18: air conditioner

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    Step 19: etc: Older models with two accessory belts have lock bolts on the tensioner bolts that must be loosened before you can turn the long tensioner bolt.

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    Step 20: Remove the three bolts holding the power steering pump to release the power steering pump bracket from the engine (12mm and 14mm)

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    Step 21: but without opening or unsealing the power steering hoses or you will need to drain it and refill it when finished.

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    Step 22: Loosen the long bolt of alternator pivoting bracket on the alternator belt to allow the adjustable accessory to pivot as tension is released.

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    Step 23: If your newer model is equipped with a serpentine belt

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    Step 24: follow those instructions in your manual and obey the diagram.

Detailed Guide

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