Mechanics

HOW DO I ADJUST THE TIMING BELT TENSIONER

1998 Mazda MPV • 140,000 miles

1998 Mazda MPV 3.0l, I am trying to install a new timing belt and I can't get the tensioner to relax so that I can put the belt on. What am I doing wrong?
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DCCJJones
November 22, 2011.



REMOVAL & INSTALLATION
TIMING BELT
Removal
Disconnect negative battery cable. Drain cooling system. Remove spark plug wires and spark
plugs. Remove air intake hose. Remove cooling fan and fan shroud. Remove drive belts.
Remove A/C compressor drive belt idler pulley. Remove retaining bolt and crankshaft pulley.
Remove coolant bypass and upper radiator hoses. Remove timing belt covers and gaskets. See
Fig. 1. Rotate crankshaft and align all timing marks. See Fig. 2.
1.
If reusing timing belt, place reference mark on timing belt to indicate direction of timing belt
rotation. Remove upper idler pulley. See Fig. 1. Remove timing belt. Remove timing belt
tensioner, tensioner pulley and lower idler pulley (if necessary).
2.
Fig. 1: Exploded View Of Timing Belt & Components
Courtesy of MAZDA MOTORS CORP.
Fig. 2: Aligning Timing Marks
Courtesy of MAZDA MOTORS CORP.
Inspection
Measure timing belt tensioner rod protrusion from end of rod to edge of timing belt tensioner
housing. Replace timing belt tensioner if distance is not.47-.55" (12.0-14.0 mm).
1.
Inspect timing belt for damaged teeth, cracking or oil contamination. Ensure idler pulleys and
tensioner pulley rotate freely. Inspect timing belt tensioner for signs of oil leakage. Replace
worn components.
2.
NOTE: The following information on tensioner pulley inspection is from
Mazda technical service bulletin 002/00R; March 9, 2000.
During the 60,000 mile inspection or timing belt replacement on MPV, inspect tensioner pulley
pivot bushing for a bronze color (wear) on the Teflon coating. If the bushing is worn, the
tensioner pulley and spacer must be replaced with the timing belt. This is to prevent a torn or
jumped timing belt.
3.
Installation
Install tensioner pulley and lower idler pulley (if removed). Install retaining bolts, and tighten to
specification. See TORQUE SPECIFICATIONS. Ensure all pulleys are clean and rotate
smoothly.
1.
CAUTION: DO NOT apply more than 2200 lbs. (1000 kg) pressure on timing
belt tensioner rod.
TIMING BELT REPLACEMENT - 3.0L - SOHC -1998 Mazda MPV ES Page 1 of 2
11/22/2011
Place timing belt tensioner in press with flat washer to prevent damage to timing belt tensioner
plug. See Fig. 3. Apply pressure on rod of timing belt tensioner until rod is retracted and holes
in rod and housing are aligned. See Fig. 3. Install pin through holes in housing and rod to hold
rod in retracted position. Release press and remove timing belt tensioner.
2.
CAUTION: If reusing timing belt, ensure timing belt is installed in original
direction of rotation.
Install timing belt tensioner on cylinder block with pin installed. Tighten retaining bolts to
specification. See TORQUE SPECIFICATIONS. Rotate camshafts and crankshaft to ensure
all timing marks are aligned. See Fig. 2. With upper idler pulley removed, install timing belt on
crankshaft sprocket, lower idler pulley, left camshaft sprocket, right camshaft sprocket and
tensioner pulley in sequence.
3.
Install upper idler pulley. Tighten retaining bolt to specification. See TORQUE
SPECIFICATIONS. Rotate crankshaft 2 full revolutions clockwise from TDC to TDC. Ensure
all timing marks are aligned. See Fig. 2. If timing marks are not aligned, remove timing belt
and reinstall.
4.
Remove pin from timing belt tensioner, allowing pressure to be applied to timing belt. Rotate
crankshaft 2 full revolutions clockwise from TDC to TDC. Ensure all timing marks are aligned.
Check timing belt deflection by applying 22 lbs. (10 kg) of force at midpoint between right
camshaft sprocket and tensioner pulley. Timing belt deflection should be.20-.28" (5.0-7.0 mm).
5.
If timing belt deflection is not within specification, repeat installation procedure. To install
remaining components, reverse removal procedure. Tighten fasteners to specification. See
TORQUE SPECIFICATIONS. Fill and bleed cooling system. Adjust drive belts to proper
tension.
6.
Fig. 3: Retracting Timing Belt Tensioner Rod
Courtesy of MAZDA MOTORS CORP.


Rivermikerat
Nov 22, 2011.