Written by MarkDTM sometime ago:
My approach to this job is.
Drain the coolant
Jack the car up and remove the two front pipe to manifold nuts (should be easy on yours as it uses the later helicoiled nuts) and remove the bolt that secures the front pipe to the gearbox bracket. Pop the front pipe of the manifold studs (takes a bit of wiggling and sometimes requires a foot on the centre section silencer to get it off) and then tie the front pipe to the gearbox to give it some support before putting the car back on the floor.
Strip the inlet manifolds off and place to one side, no need to remove the lower manifold for this job (which saves th pain or removing 12 thread locked bolts!).
Now disconnect the pipes to the heater matrix assembly (fast fit connectors, press the tabs and slide the collar back, twist the connectors a few time to free them off), disconnect the vaccum pipe that goes to the bypass valve and disconnect the pipes that attach to the coolant bridge and main coolant pipe. Now remove the bypass valve and all its associated pipe work.
This gives a nice amount of space to work in.
Removal of the header tank (again easy) gives more room to work in.
Disconnect the main radiator to coolant pipe hose at the front left of the engine and disconnect the air injection rubber coupling on the left side of the engine.
Remove the bolt on the 1-3-5 bank lifting eye that secures the coolant pipe to the engine and then remove the lifting eye (single bolt again)
Now, using a short extension on a ratchet, remove the two torx bolts (think there e12 but could be wrong) that secure the coolant pipe to the back of the block, for the right hand one you might have to ease the oil cooler pipes out the way a little.
The coolant pipe should now come out (honestly, it does, takes a bit of manouvering!).
Now spray all the heatshield bolts with penetrating fluid and go and have a cuppa.
Now remove the heat shields starting with the upper one, then the air injection pipe and finally the lower one remembering that there is a securing bolt right at the rear of the manifold to the right of the downpipe connection.
Now pop the manifold off, again shouldn't be an issue given the age of the engine as again it has the later studs.
Clean the head face well and check the manifold carefully for cracks (it seems to be only the Police that manage to crack them from my experience) before cleaning the face of it and checking its flat, I use a belt sander to flatten them off a bit (makes cleaning easier to). I also use a tap and die to clean all the threads up.
Then re-assembly is reverse of removal, I use a small wipe of silicon (cam cover sealant or similar) on the rubber O ring for the coolant pipe just to hold it safely in place when re-fitting.
You also want to clean the rear block mating surface before re-fitting the pipe....
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Topic: Exhaust manifold - cracked or gasket? (Read 1250 times)