white90 Posted August 6, 2008 Share Posted August 6, 2008 Vehicle shown is a 200TDi Defender. The 200TDi Disco is much the same - the main difference being that the turbo is under the exhaust manifold, rather than on top. Removal of both heads involves the same method. The only special tools required are a torque wrench and angle guage for the head bolts. Timing will not be affected by the removal of the head as the timing belt is not touched - however, the tappet gaps may have to be re-set, depending on the reason for removing the head and the care you take when taking it apart. Lots of pipework to remove/disconnect. Breather pipe fron oil seperator to air box- Top intercooler hose to inlet manifold - Turbo inlet hose to air filter housing - Release the two air filter housing clips, lift it up a small amount and disconnect the intake pipe. Remove the air filter assembly. Disconnect the bottom intercooler-to-turbo hose at either end and remove the steel section of pipe. You need to drain the coolant to below the cylider head - the water pump pipe is a convenient place to do this. Ctaching the coolant is difficult though - it drains straight onto the front axle, so there will be quite a bit of spillage. Disconnect the bottom radiator hose where it attaches to the pumpand allow the system to drain down. Remove the top radiator and short heater hoses. Also the thermostat housing-to-water pump elbow. At the back of the head - disconnect both heater hoses and tie them out of the way. Turbo heat shield - one fixing at the top and one at the bottom. The shield is awkward to remove - twist it clockwise and then lift it upwards. Undo the top exhaust clamp - to prevent it dropping all the way down the downpipe - put a cable tie or similar around the downpipe a couple of inches below. The downpipe may also be bolted to the side of the engine block, and this needs to be released as well. The downpipe will then drop down off of the turbo - you may have to lever on it to do this. Undo the turbo oil feed banjo bolt (15mm). There are two copper sealing washers as well. The lower heat shield fixing also has a clamp on it to stop the turbo oil feed pipe from vibrating - remove the 10mm head nut/bot. The oil feed pipe will then move away from the turbo. The turbo oil return pipe is also clamped in the same way, but where the stud extension screws into the inlet manifold, so remove the extension (12mm spanner), and remove it. There's a short steel pipe that crosses the head for the heater hose connections. 2 x 17mm nuts hold it in place. Slacken them and the pipe will come off. The inlet manifold has 4 x fixings - 2 x 10mm head bolts and 2 x 17mm nuts. Remove them and the manifol will drop down and come out from under the exhaust manifold. The exhaust manifold and turbo assembly can be removed as a single unit. The oil drain pipe is left attached and it can all be moved away from the head. Disconnect the boost pipe and tie it out of the way. Undo the remaining 17mm nuts/studs (two of them are trapped between the head and the turbo flange, so you will have to undo them a small amount, move the manifold, and then remove them completely). The two heater pipe fixings - Unplug the alternator and tie the wire out of the way. Unclip the boost pipe and tie it our of the way. The exhaust manifold and turbo will then move away from the head. The cause of an annoying ticking noise from the engine - split manifold gasket Unplug the temperature sender Remove the breather pipe that goes from rocker cover to engine block baffle plate, then the oil seperator. This is held in place by a single 8mm bolt into the rocker cover. disconnect the pipe that connects to the bottom of it. Glow plug wires next - a single connection on the front 3 cylinders (7 or 8 mm nut), and two wires on No4 cylinder. Also undo and remove the single 10mm head bolt that secures the wiring to the side of the head that you can see in the 1st picture below. The injector pipes are 17mm nut at either end. They are held together as a complete assembly by 2 x double clamps and a quadruple clap close to the injector pump. Undo all 8 x nuts and remove the pipes as a complete assembly. Expect some diesel loss as they are removed. Then the spill rail (11mm spanner). There's a small copper or alloy washer either side of each of the 4 banjo bolts, so make sure you retrieve them. Once the banjo fitting is out of the way, put the bolt and washers back in each injector. The rail can be left attached to the injector pump and carefully tied out of the way. Remove the 3 x 10mm head cap nuts from the top of the rocker cover - there should also be a cable clamp on the rearmost one. Remove the rocker cover and you will now see the rocker assembly. There are 2 x 10mm bolts and 3 x special studs that hold the rocker assembly in place. Remove the bolts completely, but only undo the 3 x studs. If you pull the studs all the way out - the rocker assembly will expand and the rockers will slide off the shaft. Lift the entire rocker assembly off the head and place it in the upturned rocker cover. Remove all 8 valve pushrods and 8 valve caps. Be careful not to drop any of the caps - they can fall all the way down into the sump. Undo and remove all 18 head bolts. This is the tightening sequence - undo the head bolts in the reverse order. Don't just wind one all the way out and then go on to the next one - slacken them progressively to prevent bending the head. 3 different sizes of head bolt - keep them in order and put them back in the right holes when you put the head back on. The head may well be stuck in place. Find a suitable point to apply leverage to the join, like this. The head will then lift off. Identifying the thickness of head gasket - holes or 'notches' 3 is usually standard. You can tell which gasket you have without having to remove the head. This section of gasket is visible at the rear of the head on the left side of the engine when viewed from the front of the vehicle. Les. 1 1 Link to comment Share on other sites More sharing options...
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