Replacing a timing belt on a 740 GL Volvo 1990 model
Replacement of the timing belt on B230F engines is fairly straightforward. Note that you will need the proper tool to secure the crankshaft sprocket during removal procedures. Obtain the timing belt tensioner as well; it is designed to last only as long as the timing belt.
Begin by cleaning the area around the timing belt upper cover.
Remove the upper cover.
Remove the drivebelts on all accessory components.
Remove the fan (if you have a mechanical fan). Carefully leverage it out of the shroud. It may be necessary to remove the shroud as well - two 7mm bolts secure it to the radiator.
Remove the lower bellhousing cover at the rear of the engine.
Turn the crankshaft to bring the engine to Number 1 cylinder, TDC, firing. The timing marks will align when this is done.
Remove the crankshaft sprocket bolt. It may be very tight, and clearance is quite limited. Take care not to move the crankshaft from its set position.
Inspect all front oil seals before continuing, along with the water pump condition. If anti-boil weeps from the weep hole on top, you must replace the water pump or else it will contaminate the new belt.
Lock the timing belt tensioner in position. This can be done with a small nail, bringing it back and out of the way.
Remove the timing belt.
Replace all oil seals that leak, are weak or missing. Oil will ruin the new timing belt.
Installation is essentially a reversal of removal, after the tensioner is replaced and unlocked, spin the crankshaft sprocket two complete turns, noting if the timing is correct by way of the pointers aligning with the marks in the rear timing cover. Push down on the belt to ensure it seats correctly. Tighten the tensioner to the specified torque.
Install the cover, rear bellhousing cover (if removal was necessary) and nuts. Screw the backplate onto the front timing cover.
Install the fan and fan shroud.
Refill the coolant if the water pump was changed.
After double-checking installation items, road test the vehicle after allowing it to warm up to check for coolant or oil leakage.
After 600 miles, remove the rubber plug at the front of the timing cover. Loosen and tighten the tensioner bolt. Place your labels indicating mileage and date of timing belt drive maintenance at the front of the engine.
May 09, 2010 |
1990 Volvo 740