Disco 4 (LR4) Left hand inlet manifold replacement

Happy new year all!

Following some great feedback on a different post (thanks again to everyone!), I've diagnosed a cracked left hand (ie on the right as you look from the front of the car) inlet manifold on my 3.0lt diesel D4. I have the workshop manual for this car and at over 9000 pages long its a beast - sadly it doesn't appear to have specific instructions for replacement of this part!

I'm keen to try this myself but as I'm not a mechanic I'd really want the instructions - does anyone happen to have these, have any experience or advice?? Would be great to hear from you!

Wishing you all open roads and trouble free motoring for 2024

Steve

Stevie135 said:

Happy new year all!

Following some great feedback on a different post (thanks again to everyone!), I've diagnosed a cracked left hand (ie on the right as you look from the front of the car) inlet manifold on my 3.0lt diesel D4. I have the workshop manual for this car and at over 9000 pages long its a beast - sadly it doesn't appear to have specific instructions for replacement of this part!

I'm keen to try this myself but as I'm not a mechanic I'd really want the instructions - does anyone happen to have these, have any experience or advice?? Would be great to hear from you!

Wishing you all open roads and trouble free motoring for 2024

Steve

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I have had the drivers side manifold off on my D3, lots to remove including the injector pipes and common rail, and the manifold was stuck to the head like stuff to a blanket, not hard but fiddly in places.
Iirc book time for both manifolds is something mad like 8 hours?

lynall said:

I have had the drivers side manifold off on my D3, lots to remove including the injector pipes and common rail, and the manifold was stuck to the head like stuff to a blanket, not hard but fiddly in places.
Iirc book time for both manifolds is something mad like 8 hours?

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I was figuring a full weekend at the very least yes! Did you work it out for yourself or follow instructions?

If you have 'the workshop manual' downloaded, then you probably have the work instructions - look for 'valve cover' within 303-01.
If you've somehow missed downloading it from Topix, I may have a copy of it somewhere.

It's not a particularly difficult job, make sure you get new injector seals and leak-off pipe 'O' rings, if you need the part numbers I should have them somewhere. The injector bolts are torqued only so don't need replacement, you can use a fuel injector as the 'special tool' to align the valve cover. I'd add that you need to clean, clean & clean again the mating surfaces to prevent oil leaks, a swipe of red rubber grease will help in this regard.

Stevie135 said:

I was figuring a full weekend at the very least yes! Did you work it out for yourself or follow instructions?

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I never use instructions for anything, but tbh it was not hard just lots of fiddly fasteners in awkward places, basically keep unbolting stuff until it comes off.
I spent quite some time sorting out the wiring conduit that had fell apart from the heat, and clipping the wires up neatly so they did not rub in the future.
In this pic I have the cambelt off as well, not sure if it has to come off, but it was a while ago that I did the job (camchain tensioner) and I cannot remember!

lynall said:

I never use instructions for anything, but tbh it was not hard just lots of fiddly fasteners in awkward places, basically keep unbolting stuff until it comes off.
I spent quite some time sorting out the wiring conduit that had fell apart from the heat, and clipping the wires up neatly so they did not rub in the future.
In this pic I have the cambelt off as well, not sure if it has to come off, but it was a while ago that I did the job (camchain tensioner) and I cannot remember!
View attachment 306518

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Many thanks! May be worth me doing the cam belt at same time then

Stevie135 said:

Many thanks! May be worth me doing the cam belt at same time then

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The cambelts are not as hard or as scary as people make them out to be, cheap timing pin kits on ebay etc.
Iirc dealer price for cambelt and fuel pump belt is something like 1k.

That price would include the service items as well, in 2017/8 the two belts were ~£600 with the service bits coming in at ~£300
The front belt used to take me about 35-40 mins, probably an hour now as I've not done one for a while. The rear belt took about the same on the 3.0l, 20 mins or so on the 2.7l. I wouldn't do one now, I'd leave it to the kids with skin still on their knuckles and more flexible joints.

Hi all, update!

I’ve completed replacement of the inlet manifold and what a pain in the bum it was!! Engine cranked for a good 20 plus seconds then started sounding very rough etc but as it continued to prime and water started to get round, it started to sound pretty good.

Worrying however - getting smoke from down the side of the inlet manifold next to the foam injector soundproofing and indeed from under the lid of this foam…. Continued to smoke for 5 to 10 mins at idle - on turning off I noticed both sides smoking! I haven’t been anywhere near the right hand side honest Sort of a sooty smell to the smoke. Can’t make it out very well on the pic but there’s enough of it.

The only thing I’ve touched on the right was a plastic pipe that runs to a t piece behind the oil filter and then runs to left hand side inside the injectors soundproofing.

Any thoughts on the smoke? Any advice greatly appreciated thanks!

Steve

Give it a good rinse off with brake cleaner, with the engine off, and allow a good while for it to dry before starting the engine, I reckon your smoke is spilt diesel.

Stevie135 said:

Hi all, update!

I’ve completed replacement of the inlet manifold and what a pain in the bum it was!! Engine cranked for a good 20 plus seconds then started sounding very rough etc but as it continued to prime and water started to get round, it started to sound pretty good.

Worrying however - getting smoke from down the side of the inlet manifold next to the foam injector soundproofing and indeed from under the lid of this foam…. Continued to smoke for 5 to 10 mins at idle - on turning off I noticed both sides smoking! I haven’t been anywhere near the right hand side honest Sort of a sooty smell to the smoke. Can’t make it out very well on the pic but there’s enough of it.

The only thing I’ve touched on the right was a plastic pipe that runs to a t piece behind the oil filter and then runs to left hand side inside the injectors soundproofing.

Any thoughts on the smoke? Any advice greatly appreciated thanks!

Steve
View attachment 307902

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Wondering if I’ve worked out what it was…. Had the larger under plate off to recur a spanner - think it may have been diesel heater blowing under car and coming back up round the engine! Hence why it continued to smoke when engine off… we shall see!