A common issue on the TD5 engine (be it Defender or Discovery) is that the Exhaust Manifold warps slightly and this snaps the studs holding the manifold to the engine block. Typically it is the front and rear port studs that snap, although I was fortunate to only lose the front port studs.
A number of fixes are available for this problem, the effectiveness of which is the subject of debate. In order they are:
1) Cutting the webs between the manifold ports out (This is actually the method used by my local dealership!) - £Free for a bit of effort.
2) J E Engineering do a stud and spacer kit which replaces the existing studs with bigger ones. Cost of this was £35 + £5 P&P +VAT = £47
3) TD5Alive have a Ceramic Insulated manifold available. This has a ceramic coating which insulates it very well – we ran the engine for a few minutes and could still touch the surface of the manifold easily. This is £325 + £10 P&P +VAT on their website, but DOC members should remember a 10% discount is normally available from Gary for club members. There is the ability to return your manifold to him for a rebate also.
Personally, I don’t rate the idea of cutting the webs as Land Rover designed the part this way (although some dealers are doing this themselves!) and it can still re-occur. My fix for this was to combine the TD5Alive manifold with the J E Engineering stud kit. This decision was taken due to some discussions I had read that suggested that the strength of the Land Rover supplied studs was not the best available, although you should remember that some modifications like this could have ramifications further down the line if the Land Rover engineers deliberately put the studs in as the weak point in the design to relieve potential stresses.
So what do you need to change the Manifold? Here’s the parts list:
1x LKG100470 Block to Exhaust Manifold Gasket
1x ERR6768 Exhaust Manifold to Turbo Gasket
10xTE108051L M8x25 Studs
10xESR2033 M8 Flanged Nuts
1xLVJ000010 Coolant Elbow Gasket (If your front studs are snapped you are better off taking the coolant elbow off for access)
2xADU6847L Copper Washers (Turbo Oil feed banjo)
1xPYP100008L Bleed ScrewIf you buy the J E Engineering stud kit, there is no need to buy either studs or nuts as these are included. The nuts he supplies have courser teeth on the back to the standard LR ones.
Here’s a photo of my Manifold before:
1. Snapped StudsHow do you change the Manifold then?Firstly a word of Warning – I am not a Mechanic, the destructions that follow are written from memory although I have been present and helped with two Exhaust Manifold changes, the first went badly wrong and ended up with a stud extractor snapped in the head and impossibly stuck. This was a few years ago however and the individuals involved have been flogged for their sins. It also wasn't my truck. This one didn’t go perfectly either, so please bear that in mind when you attempt this yourself. I will accept no responsibility for the divorce that ensues when Her Indoors finds out what you have done, or for any damage you may do.To prepare for the surgery, I took the Discovery for a brisk drive from Bristol to Charfield up the motorway to the dealership to pick up some gaskets, then down to JC Land Rover in Oldbury-Upon-Severn for the work. It was left to cool for about 20mins before we attacked it. IMHO the heat generated here can aid the efforts to remove the studs easily.
To remove the manifold, you must first remove the following parts in order:
1) Engine Accoustic Cover (Big Black Bit!) – 2x13mm Bolts on the exhaust manifold side, 1x13mm Bold on the inlet manifold side. Should lift off then, sometimes removing the oil filler cap can help.
2) The heat shield needs to come off from the turbo, IIRC it is two bolts on top that also hold the metal water pipe in place (the upper bolts on the water pipe need to come off, as does the lifting bracket). A third bolt is accessed through a hole in the back of the heat shield, and is a [!Expletive Deleted!] to get off. We were able to grind off the pop-rivets holding the heat shield to the bracket as one side of the bracket had cracked off anyway.
3) If your vehicle has A/C then the A/C pump needs to come off. Loosen the drive belt and then 4 Bolts around the head are removed and unplug the electrical connector.
You can begin removing the nuts from the studs. Careful as you do this in case you snap more studs. If you snap a stud (or already have snapped studs) then you will need to first drill down the centre and then attempt to use a easy-out stud extractor to remove the stud. If you drill it right, you should get to a point where the stud suddenly “pops” and winds down to the base with the drill. Then it should unscrew easily with the easy out. Go carefully here!
Of course, in order to recover the studs, you need to remove the manifold. If your vehicle has an EGR, now is an excellent time to remove that, otherwise just unscrew the EGR pipe work for the time being from the EGR port and set to one side.
You now need to undo the 3 nuts holding the manifold to the turbo. Once done, you must then undo the Oil Feed Banjo Bolt from the top of the turbo, as well as removing the engine breather tube from the inlet pipe work, and the pipe from the MAF sensor to the turbo (secured with two jubilee clips). Careful as you do this if you’ve not bought new copper washers as the lower one often drops off. The turbo will now push backwards to give you enough room to pop the manifold off the studs front and back.
You should be able to wiggle it out and you will probably be presented with this sight:
2. Snapped Studs & Carbon DepositsAs you can see, two studs (the front ones) have snapped, and you can see the carbon deposits around the manifold port. As the top one is obscured by the coolant elbow, you’ll need to undo the three bolts here and remove it. We didn’t do this, and as a result managed to drill the stud at an angle which made removal impossible, as well as causing us to have to re-tap the hold and only able to screw the new stud in about 10mm. It is also tapped at an angle which made things interesting to re-fit the manifold (we had to re-fit the studs with the manifold hooked into place on the front studs.) however all of our studs came out cleanly due to the engine heat.
The following images give you an idea of the process.
3. Stud being extracted by a Easy-Out4. Head being re-tapped5. Technique for removing studs6. J E Engineering Stud with spacer, EGR blanked.7. Manifold being Re-FittedSo to remove the studs the easiest method is to pop two nuts back to back and tighten them on one another. Then back the top nut off and the stud should follow. If it doesn’t, you need to consider how much force you apply – too much and you will snap the stud, too little and you may not shift it. My studs were all easy to remove and came freely with no problems apart from the front two which had snapped.
Once your new studs are in you can re-fit the manifold. Pop the new gasket on and then slip the spacers on (if you’re using the J E Engineering Stud Kit) and add nuts on top. A mallet may be needed in some instances to tap things gently into place.
Gently tighten them as much as you dare! Remember, sods-law dictates that the last one you do up is the one you will snap ;) You can then add the next gasket and re-connect it to the turbo. Replace the Oil Feed banjo with new copper washers if you bought them, or follow the usual methods for re-using the copper washers. The A/C pump can be popped back into place and screwed down, and then the Coolant Elbow and pipes can be re-attached with a new gasket also. The Lifting bracket can be re-attached and then the heat-shield can be bolted back on. The top water pipe will be held into place using the bolts on the heat shield and two bolts to the head.
Replace the inlet pipe doing back up the jubilee clips between the turbo and the air box. Replace the breather pipe and check for wear on your wastegate actuator where this rubs against it. When I first bought my car, this had worn through and was preventing my turbo from working properly.
Check the A/C pump is secure, re-attach the drive belt and you should be looking at what you see in the next picture:
8. FinishedYours would also have the acoustic cover fitted also; I’ve left it off here to show where everything fits better. Re-fill your coolant if you drained it, or top back up and bleed the top hose using the bleed screw. I’ve included one on the parts list as you can never be too careful and they are plastic so could snap if it’s cold and you are ham-fisted with it.
This last (blurry sorry) picture shows the OEM stud versus the J E Engineering Stud, and the Spacer supplied with the kit.
9. Stud ComparisonCongratulations. It’s now dark and this would be a good time to go indoors and see your Children, they’ve probably forgotten what you look like again. Or you could take it for a spin...