Changing Water Pump

PARTS & TOOLS REQUIRED:

10mm, 12mm and 14mm sockets and spanners
a variety of socket extensions
a container for coolant (capacity – up to 5 litres)

The water pump is fitted to the back of the engine on the left hand side. It is one of the more awkward parts to get to. This procedure requires the use of axle stands or a garage lift – a jack is not safe. It may be possible to do the job entirely from above by removing the inlet manifold entirely.

Water pump
34mm ID x 1.0mm cross section ‘o’ ring

PROCEDURE:

ABOVE CAR

disconnect battery

drain coolant into container – there is a plastic wing nut on the bottom of the back side of the radiator

undo various hoses and electrical connectors to make room.

undo alternator adjuster (12mm)

remove dipstick

undo and remove dipstick tube (screw at top – 12mm). Alternator adjuster arm comes off with it. Block hole in sump where dipstick tube enters sump to prevent water and dirt getting into the engine oil.

undo and remove top water pump bolt – 12mm

BELOW CAR

remove alternator belt

undo bottom alternator bolt and nut (14mm) and move alternator out of way

undo bottom water pump nuts – 2 nuts, both 12mm

locate pipe running across block from water pump – notice it is screwed to block with 10mm screw. Undo.

using screwdriver or pry bar, lever between notches and water pump – any coolant in these pipes will leak!

water pump can now be removed from block

water pump nose can now be separate and changed with new, if not complete.

REFITTING

Refitting is the exact reverse of removal.

The original water pump was originally sealed to the block with gasket sealant, however this may not provide an adequate seal and any gasket compound may get disturbed when trying to refit. Suggest fitting an ‘o’ ring in the sealant groove – a 34mm ID x 1.0mm cross section ‘o’ ring (max 1.25mm cross section) superglued in place in addition to gasket compound should make a good seal. Any gasket compound should be used sparingly.

Note: refitting the 10mm screw that supports the water tube that exits the water pump can be difficult to refit.

Make sure that alternator is tensioned properly.

Make sure that any air locks in the coolant system are removed and also the correct level of antifreeze and corrosion inhibitor is in place.