- Rotate the engine so that No. 1 cylinder is at Top Dead Center (TDC) on
the compression stroke. Check that the timing marks are aligned on the camshaft
and crankshaft pulleys. An access plug is provided in the cam belt cover so
that the camshaft timing can be checked without removal of the cover or any
other parts. Set the crankshaft to TDC by aligning the timing mark on the
crank pulley with the TDC mark on the belt cover. Look through the access
hole in the belt cover to be sure that the timing mark on the cam drive sprocket
is aligned with the pointer on the inner belt cover.
NOTE: Always turn the engine in the normal direction of
rotation. Backward rotation may cause the timing belt to jump time, due
to the arrangement of the belt tensioner.
- Drain cooling system. Remove the upper radiator hose as necessary. Remove
the fan blade and water pump pulley bolts.
CAUTION
When draining the coolant, keep in mind that cats and dogs are attracted
by ethylene glycol antifreeze, and are quite likely to drink any that is
left in an uncovered container or in puddles on the ground. This will prove
fatal in sufficient quantity. Always drain the coolant into a sealable container.
Coolant should be reused unless it is contaminated or several years old.
- Loosen the alternator retaining bolts and remove the drive belt from the
pulleys. Remove the water pump pulley.
- Remove the power steering pump and set it aside.
- Remove the 4 timing belt outer cover retaining bolts and remove the cover.
Remove the crankshaft pulley and belt guide.
- Loosen the belt tensioner pulley assembly, then position a Camshaft Belt
Adjuster tool T74P-6254-A, or equivalent, on the tension spring roll pin and
retract the belt tensioner away from the timing belt. Tighten the adjustment
bolt to lock the tensioner in the retracted position.
- If the belt is to be reused, mark the direction of rotation on the belt
for installation reference.
- Remove the timing belt.
| Fig. 1: Camshaft, auxiliary shaft and crankshaft
timing belt sprocket alignment mark locations — Mazda
B-Series Pick-Ups 1997 2.3L (VIN A) and 1998–01 2.5L (VIN C)
engines
|
To install:
- Install the new belt over the crankshaft sprocket and then counterclockwise
over the auxiliary and camshaft sprockets, making sure the lugs on the belt
properly engage the sprocket teeth on the pulleys. Be careful not to rotate
the pulleys when installing the belt.
- Release the timing belt tensioner pulley, allowing the tensioner to take
up the belt slack. If the spring does not have enough tension to move the
roller against the belt (belt hangs loose), it might be necessary to manually
push the roller against the belt and tighten the bolt.
NOTE: The spring cannot be used to set belt tension; a
wrench must be used on the tensioner assembly.
WARNING
If any binding is felt when adjusting the timing belt tension by turning
the crankshaft,
STOP turning the engine, because the pistons may be hitting
the valves.
- Rotate the crankshaft 2 complete turns by hand (in the normal direction
of rotation) to remove slack from the belt. Tighten the tensioner adjustment
to 26–33 ft. lbs. (35–45 Nm) and pivot bolts to 30–40 ft.
lbs. (40–55 Nm). Be sure the belt is seated properly on the pulleys
and that the timing marks are still in alignment when No. 1 cylinder is again
at TDC/compression.
- Install the crankshaft pulley and belt guide.
- Install the timing belt cover.
- Install the water pump pulley and fan blades. Install the upper radiator
hose if necessary. Refill the cooling system.
- Install the accessory drive belts.
- Start the engine and check the ignition timing. Adjust the timing, if necessary.
