Take 2….
Now equipped with the right tools, I’ve had another go at the EGR mod and have decided to remove the whole EGR unit (I’ll keep it just in case it ever needs to go back on for some reason). I also wanted to remove the inlet manifold and give it a thorough clean while I’m at it.
I bought some extra tools, noting that I started to round off the EGR bolts on the exhaust manifold side during my first attempt the other day. I therefore bought a set of Laser six-point spanners (about £50) and also a Silverline damaged bolt remover kit (about £20). In the end, the six-point spanners did the trick even on the nuts that I had already started to round off.
As a guide to anyone else looking to remove (or blank off) their EGR and give the intake a general clean up, this is how I went about it…
Remove intake pipework from air filter to turbo… 10mm clip at turbo end plus bolts on two plastic legs holding pipework down to head (12mm I think), and one electrical connector to unplug. I also removed the airbox itself to create a bit more room to work, as it’s only held in by three easily accessible 12mm bolts.
Then off with the metal intake that runs from the turbo to the inlet manifold. A pinch clip on the turbo side and four 12mm nuts attach it to the butterfly housing on the inlet manifold. There are two electrical plugs to disconnect and four vacuum hoses at the back near the bulkhead. There is also a clip around one of the heater matrix coolant hoses, which needs to be unbolted from the metal intake. There are also two throttle cables to disconnect.
Next there are two arms bolted to the head, which carry the throttle cables. Remove these as it will create space and make it easier to wriggle out the metal heat shield from around the exhaust manifold, which needs to come out next… five 10mm bolts hold the shield in place and some are awkward to get at. The shield will feel like it won’t wriggle free but be brave and it will come free if you pull upwards and outwards, away from the exhaust manifold.
You should now be looking something like this (I’ve covered the exposed turbo ports with plastic to stop anything dropping inside them). The butterfly housing in the second picture only looks like this because I cleaned it when I aborted the EGR job previously…it was caked in black goo!
I also disconnected the heater control bracket from the bulkhead (10mm nut) as this will improve access for later.
I then attacked the EGR fixings at the exhaust manifold end, hoping that I could remove the inlet manifold later with the EGR still fixed at that end. This didn’t work out as there wasn’t enough room to wiggle the parts free (the EGR pipework runs through a tight space between the rear of the head and the bulkhead), so I also had to remove the EGR fixings from the inlet manifold end while it was in situ.
Firstly the EGR fixings on the exhaust side… a 12mm nut on stud is upper fixing, and a 12mm bolt is lower. This is where the six-point spanner came into its own. There isn’t much room but once the nut/bolt is cracked off, it wasn’t too bad. I had already removed the top nut before I took the photo.
If you are blocking the EGR (rather than removing it), you need to sandwich a blanking plate between the EGR pipe and the exhaust manifold. Do this now and reassemble…you’re done!
I wanted to lose the whole EGR though, so onwards…
Then the EGR fixing on the inlet side is two 12mm nuts. Again, awkward to get to but easy enough once cracked off. There is a vacuum hose and an electrical plug connected to the bottom part of the EGR unit (below the flying saucer thingy). Disconnect these and I would advise you to separate the lower part of the EGR by undoing the two small bolts, as it will make the next step easier.
You are now ready to wiggle out the EGR (assuming you are removing the unit). Hope you like swearing! It is a tight fit and the studs sticking out of the inlet and exhaust don’t help much. I used a pry bar to encourage the EGR body past the studs and after some trial and error, found that moving the whole unit towards the exhaust side of the engine bay was the way to go. I was then able to twist and wiggle it out by bringing it upwards over the back of the rocker cover. Once it’s out, this is what you have removed (note the bottom part separated as mentioned above…don’t think I would have got the EGR out with this still fixed in place) …
I then blanked off the hole in my exhaust manifold with the smaller of the two blanking plates supplied in the kit I bought off eBay (RTG Automotive £8.99), using exhaust sealing paste to ensure a good seal. The original nut & bolt will hold the plate without the need for any spacers on the exhaust side.
I then set about removal of the inlet manifold, to give it a good clean. The manifold itself is held in place by eight 12mm nuts. All are easily accessible, except the lower rearmost one – again prepare swearwords! You will need to remove a few other bits that are bolted onto the manifold and remove some of the bolts fixing the power steering fluid reservoir, so that you can swing it away from the manifold, to give room to slide it off the studs. I then uncoupled the diesel injector pipes, and cable tied some plastic around the open ends to avoid contaminating them. Ensure that the various plastic guides & clamps holding the fuel pipes are removed, so you can gently bend the pipes out the way as you draw the inlet manifold off its studs.
Having removed the inlet manifold, I realised how awful the EGR system is. The insides were caked in about 5mm of syrupy black sludge! I used a round edged palette knife to scrape as much of this out as possible, then bathed the insides with petrol and went to work on scrubbing the bores with old toothbrushes. I then finished it off with brake cleaner and the bits I could get to have come up nice and shiny. I did the same on the exposed inlet bores in the cylinder head, which were in the same state. I also fixed the larger of the EGR blanking plates from the set onto the inlet manifold. The studs are not threaded all the way down their length, so you need to make up some spacers prior to using the original nuts to hold the blank in place. I added some silicon gasket on this for good measure. Here’s how the manifold looked prior to refitting…
I then refitted everything, primed the diesel pump to get rid of any air in the fuel lines and while I had the airbox out of the way, I bled off the water trap in the bottom of the diesel filter. The bled off fluid looked nice and clean though.
When I first started the engine, there was a nerve jangling ‘diesel knock’ and I turned the ignition off immediately. I tried again and got same result. Then a third time and all was normal. I presume that the remnants of brake cleaner and/or petrol fumes in the intake system caused this and it quickly burnt off.
I then carefully ran a can of EGR cleaner through the intake for good measure, in the hope that any sludgy mess that I couldn’t reach will be cleaned out.
I’ve got a run from Cornwall to the Scottish Highlands and back next month, so will be interested to see how she drives and what MPG I’ll be getting.
Hope this helps anyone who is looking to do the EGR mod on a 3.0TD (there are some different procedures with doing this mod on the D4D engine). Thanks to those who offered forum advice to me previously and feel free to correct anything that I might have got wrong.