Major Service

Overview of the VR-4 Major Service

The major service on the VR-4 is considered to be the biggest and most complex service with the following details:

Frequency	Core Tasks	Optional Tasks
Every 100,000km	Replace Timing Belt Replace crankshaft oil seal Replace Water Pump Replace Coolant Replace Timing Belt Tensioner Replace Timing Belt Tensioner Pulley	Replace camshaft oil seals Replace harmonic balancer Replace alternator belt Replace AC/Power steering belt Bleed Brakes Replace Transmission/ATF fluid Bleed Clutch Replace Transfer Case fluid

Required Tools

The tools you will need for the major service will depend on whether you are performing just the core service or all of the optional tasks. We list the tools here for each, plus alternative tools (where possible) if you do not have the recommended tool.

Tools for Core Tasks

Tool	Purpose	Alternatives	Notes and examples
1/2" socket set	Removal of various bolts	Spanners (if you're a mad lad).	Socket set will need to include 10mm through 17mm, and 19mm through 21mm. Many of the
3/8" socket set	Removal of various bolts in the harder to reach places	Spanners or trying to do it all with a 1/2" socket set
Open and ring spanner set	Removal of bolts and nuts that cannot be reached with sockets, or holding nuts on the other end of bolts you are removing with the socket set.
Camshaft sprocket holder	Inserting into the two guide holes to hold the crankshaft pulley (harmonic balanacer) while you remove the bolt.	Breaker bar inserted into harmonic balancer bolt head, followed by tickling the starter motor	Whilst this is a cam sprocket holder, the 6A13 harmonic balancer has two guide holes that allow use of this type of tool. The Mitusbishi service manual specifically mentions tool MB990767 and the right size pins (MD998715) for holding the pulley.
Very powerful 1/2" impact gun	Removal of harmonic balancer bolt	Breaker bar	If restraining the harmonic balancer using a cam sprocket holder, the impact gun needs at least 1,500Nm of nut busting torque. If you do not have such a tool, you can try a breaker bar.
Small 10mm open ended spanner	Removal of the timing cover bolt behind the Power steering pump bracket	Removal of the power steering pump bracket before accessing this bolt.	Seriously, this one bolt will make you rage.
Timing belt tensioner wrench (socket)	Tensioning and holding the timing belt in position so you can then tighten the tensioner pulley cam.	A screwdriver and feel.	Mitsubishi list this tool as part code MD998767 but these can be purchased from eBay by searching for terms like "Mitsubishi Belt Tension Tensioner Adjuster Pin Wrench Timing Tool". If you don't have access to this tool, you don't need the beam style torque wrench either. In that case you tension the belt by levering the tension of the pulley using a screwdriver braced against the alternator bracket. This is an inaccurate method but likely to result in an over-tight rather than loose belt given the low torque (3Nm) required to tension the belt.
Beam style torque wrench 1/4" or 3/8" with adapter	For use with the timing belt tensioner wrench	A regular style of torque wrench can be made to work but needs to go down to under 3Nm	If you don't have access to a torque wrench, use the screwdriver method as above.
Oil seal removal tool	For removing the crankshaft oil seal	Small drill bit and self tapping wood screw	If you do not have an oil seal removal tool (search eBay for the term "Shaft Type Seal Puller"), you can carefully drill a small hole in the oil seal, screw a self-tapping screw into that hole and then pull on the screw with pliers. Make sure you do not scratch either the crankshaft or the block where the oil seal mates to.
Gear locks	Locking the camshafts in TDC position while you replace the belt.	Bulldog clips to hold the timing belt onto the cam sprockets.	When replacing the timing belt, you can either use cam locks to hold the cams into position for the entire duration of the work, or you can just: Hold the cam sprock in position with a ring spanner on the cam sprocket bolt Slip the new timing belt onto the sprocket Check that the crankshaft and cam timing is correct Place a bulldog clip to hold the belt onto the sprocket Move to the next cam sprocket and repeat steps 1-4 This is the Mitsubishi recommended method in the service manual.