Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[omegod]

Well looks like it isn't the downpipe gasket blowing so that leaves the manifold one as the cuprit for my leak, never done one before but believe an expert can do one in three hours in a field!

Any tips welcome and how the fook does the big metal pipe come out? Haynes talks about draining the oil and taking the plenum off, do you really need to???

[amba]

 Re: Drivers side exhaust manifold removal V6


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.... 

 
Will need to do 2 posts as write up exceeds forum guidelines 

[amba]

And the shopping list (prices probably well out of date now):

                                               Part no.         Price 
Exhaust downpipe nuts M10 x 2      90570845       
Manifold gasket                       24416110           
Manifold nuts x 7                 11082413           
Manifold studs x 7                 90106924           
Coolant pipe O-ring                 9128362           
Front pipe gasket                 90499289             
Secondary Air Injection gaskets x 2            90467427 

[Elite Pete]

Got one to do on Monday

[omegod]

Cheers amba, cracking guide, Pete if I wasn't so skint you would be doing mine on Tuesday

[spanish_lad]

i wish mine was that side and not the other ..hahaha

cant find any "half nuts" anywhere to get the snapped stud out, i might have to weld a nut on the end of the stud instead 

[amba]

Don,t suppose you have got a stud extractor socket ?.

Assuming you have enough working space to get socket and ratchet into...it looks a bit like a sparkplug socket with roller guides inside.As you tightened it up on the stud the roller grip the stud and act as a reverse thread and hopefully withdraw the stud.

That should work if you have some thread showing .

[amba]

Similar to these found on the "bay"    261112113018

Not sure how to post link  but listing number will get you there

[omegod]

Quick question, are the studs to attach the downpipe to the manifold replaceable i.e can they be removed with the double nut technique? seem to recall a mangled thread

[amba]

Yes ,the studs are available but think I ended up having to buy 4 as thats how VX bag them although I did replace them all anyway along with new copper nuts,helicoiled.

They are a pig to undo and really need some heat applied so when you get manifold off take a trip to local garage and ask them to warm them up abit..makes life easier if you havent the gear to hand.

[omegod]

Re: Drivers side exhaust manifold removal V6


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.... 

 
Will need to do 2 posts as write up exceeds forum guidelines

Sorry Amba, What do you mean by inlet manifolds? the Plenum or the black bits underneath? I have LPG injectors tapped into the underneath bit so need to be a bit careful there, sorry for a dim question but venturing into parts I have not removed before

[amba]

Black bit underneath  ..its the sandwich plate and whilst it will slightly improve access ,its not totally necessary .

[omegod]

Ok seem to be getting there with this, undone a million coolant pipes but still struggling to get the lower matrix pipe off but sure it will succumb to a bit more brute force.

Not sure where the metal coolant pipe attaches to the block though,I think I am getting confused but do I need to remove the metal manifold directly under the plenum,the bit with the lpg injectors tapped into it but can leave the sandwich plate in place, !, would rather have left this alone but if needs must? plus there is a smaller metal pipe running under the fat one does this need to come out too?? 

Cheers for the help so far

[amba]

To give you access to the coolant transfer securing bolts at the back of the block you will need to strip away 3 seperate sections..top plenum/fuel injector manifold(bit with lpg attached) / bottom  black sandwich plate.

Once they are all removed you will be left with just the coolant bridge at the back of the V which has 3 coolant pipes attached and 2 electrical connecters.If you have small hands and are good at working blind you may be lucky and be able to get the 2 coolant transfer pipe bolts undone with this in place ,although as with most things on an Omega the better access you can get the easier the job is.Transfer pipe is also secured to the engine lifting eye just below plug # 3 so that will also require removal.Coolant pipe will come out but requires a bit of manouvering as its a strange shape.Once out remove black sealing ring from groove in end or might be stuck to back of the block..ensure this surface is clean before refitting coolant pipe with new 0 ring as per guide.

[omegod]

Well this is turning into a right pain in the arse, due to the LPG pipes being threaded through the intake manifold I could hardly get to the nuts and the it wouldn't come out for love nor money, had to remove the fuel rail and injector connectors/injectors to make room enough for it to shift. Removed the coolant bridge as I have large hands Is there usually a washer under both bolt's as only one had one?

Had to give up after removing the big coolant pipe,heatshields and the top three manifold studs came out a treat but will tackle the other 4 after picking up the new parts from Vaux tomorrow.

Really not sure it will work again as there are about twenty pipes/connectors that need to go back in the same place