Mechanics

TIMING BELT TENSIONER

1988 Mazda 323

Engine Mechanical problem
1988 Mazda 323 4 cyl Front Wheel Drive Manual 350000 miles

I had to replace the water pump on my car, when I took on the task of disassembling the car to replace it I notice debris underneath the timing belt. Further dis assembly lead to me to discover that the bolt that holds the timing belt tensioner in place had sheared off. I was wondering if I have any alternatives to pulling the engine and drilling out the remaining part of the bolt. There are two bolts that go into the engine underneath the tensioner, but I didnt want to remove them not knowing what the really went to. Any advice you could give me would be greatly appreciated, thank you for your time.
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Lawsonca
January 2, 2009.



This is how to change the tensioner on the nonturbo and the turbo models

323 Models

NON-TURBO

Disconnect the negative battery cable. Remove the engine side cover.
Remove the power steering and air conditioning belts, if applicable.
Remove the alternator drive belt and the alternator.
Unfasten the bolts and remove the water pump pulley. Unfasten the bolts and washers, then remove the front portion of the crankshaft pulley together with its spacer.
Tag and disconnect the spark plug wires, then remove all four spark plugs (to make crankshaft rotation easier).
Unfasten and remove both the upper and lower timing belt covers along with their gaskets.
Remove the bolt mounting the timing belt tensioner to the front of the block. Remove the washer, the tensioner spring and the tensioner. If you plan on reusing the belt, be sure to mark the direction of rotation before removal.
Inspect all parts. Check the tensioner for rough rotation. Check the condition of the tensioner spring and replace as necessary.
To install: Position the tensioner on the block, then install the bolt and washer, just starting the threads. Connect the spring and slide the tensioner as far as it will go to the left (away from tensioning the belt), so that spring tension is maximized. Tighten the bolt enough to hold the tensioner in this position.
Torque the tensioner lockbolt to 14-19 ft. Lbs. (19-26 Nm). Place a ruler near the right side of the belt at the center of the span. Depress the belt with a thumb (to produce approximately 22 lbs. Or 10 kg pressure) and measure deflection. The belt should deflect 0.35-0.39 in. (9-10mm) on 1986 models, 0.35-0.51 in. (9-13mm) on 1987 models, or 0.47-0.51 in. (12-13mm) on 1988-89 models. If tension is incorrect, do not try to tension the belt by hand. Instead, fix any binding in the mechanism, if necessary; otherwise, replace the tensioning spring.
Install the timing belt covers, using new gaskets if necessary. Torque the bolts to 69-95 inch lbs. (8-11 Nm).
Install the spark plugs, torquing to 11-17 ft. Lbs. (15-23 Nm), then connect the plug wires.
Install the baffle plate along with the crankshaft pulley and washer, torquing the pulley bolts to 11-13 ft. Lbs. (15-18 Nm). Install and properly tension the drive belts.
Install the engine side cover. Connect the negative battery cable.
TURBO

Disconnect the negative battery cable. Remove the engine side cover.
Remove the required accessory drive belts. Remove the water pump pulley and crankshaft pulley.
Support the engine with a suitable hoist and remove the No. 3 engine mount installation bolts, then lower the engine in order to remove the air conditioning/power steering pulley and the crankshaft pulley.

Rotate the engine so that the No. 1 piston is at TDC.
Unfasten and remove the upper, middle and lower timing belt covers along with gaskets from the mountings.
Remove the baffle plate. Remove the timing belt tensioner and spring by disconnecting the spring from its anchor, then loosening the tensioner bolt.
Check the tensioner for rough rotation.
To install: Connect the spring to the tensioner, then install the spring and tensioner with the attaching bolt. Move the tensioner to the left until the spring is fully extended and temporarily tighten the tensioner bolt to hold it in place. Torque the tensioner lockbolt to 27-38 ft. Lbs. (37-52 Nm).
Measure the belt tension by applying 22 lbs. (10 kg) of pressure between the camshaft pulleys. The deflection should be 0.33-0.45 in. (8.5-11.5mm) between the two pulleys. Loosen and tighten the tensioner, as required, to adjust the tension.
Install the lower and upper timing belt covers, using new gaskets if necessary. Install the spark plugs and connect the plug wires.
Install the baffle plate, with the curved surface facing outward. Install the crankshaft pulley and, where applicable, the air conditioning/power steering pump pulley. Torque the pulley bolts to 9-13 ft. Lbs. (12-18 Nm).
Raise the vehicle and install the No. 3 engine mount bracket. Torque the bolts to 44-63 ft. Lbs. (60-85 Nm), then remove the lifting equipment.
Install and properly tension the drive belts. Install the engine side cover.
Connect the negative battery cable. Check and/or adjust the ignition timing as required.

Jnovack
Jan 2, 2009.