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Freelnder 1.8 timing belt after it snapped


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his thread is how to repair a Freelander 1.8i engine after the timing belt has snapped.

Information includes replacing the bent valves, re-grinding them, setting the timing, replacing the head gasket, replacing the timing belt, and any other work involved.

Failure of the belt isn't solely down to failing to replace the belt at specified intervals. Water pump failure, tensioner failure, idler wheel failure, oil contamination - can all cause the belt to snap or slip. In this instance though, the fan belt broke, got jammed behind the crankshaft pulley, and then into the bottom of the timing case, which then broke the timing belt.

The engine is known as an 'interference engine' in that timing belt failure means that there will be valve-to-piston contact, resulting in bent valves.

Once the problem has been identified, the crankshaft has to be set in the timing position. In this case that means that all 4 pistons are level - halfway down the bore.

Remove the 5 x 8mm head bolts that retain the top timing cover.

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Raise and support the drivers side front and remove the road wheel and inner engine cover (3 x 10mm head bolts)

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You will now be able to see the crankshaft pulley.

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The crank bolt now needs to be removed. There are several ways of doing it - jamming the flywheel after removing the dust cover -

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A rattle gun, or a socket and bar on the bolt and then flick the starter.

Two fan belts on this engine - alternator belt and PAS belt. The Pas belt tensioner is spring loaded, so a 13mm socket on it and lever downwards to release tension and then lift the belt off.

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The PAS tensioner wheel needs to be removed in order to get at one hidden lower timing case bolt, so a 6mm allen key in the centre and the wheel will come off.

Note also that the PAS tensioner looks identical either side, but the centre is offset and if you put it back on the wrong way round, it'll jam against the housing.

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Air con/alternator belt next - this has a mechanical tensioner, so slacken the centre nut (15mm I think), then the concealed adjuster bolt until the belt is loose enough to remove. Note the path the belt takes.

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Remove the crankshaft bolt, washer, and the pulley. You will now see the timing belt sprocket (and what caused the belt to fail :) )

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Undo the remaiming 3 x 8mm head bolts and remove the lower timing case cover.

There are two pips on the timing belt sprocket - re-fit the crank bolt and turn the engine until the timing is set like this -

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Now to the top of the engine. Put the wheel back on and lower the vehicle - the engine sits quite deep, so this will help. Place a jack under the sump - cushioned with a bit of wood, then rasie the jack until the engine starts to lift.

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Remove the two top engine mounting bolts (15mm head), then lower the engine a small amount until the mounting seperates from the engine - remove the old timing belt.

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Undo the 2 philips screws that retain the spark plug cover, then disconnect the plug leads, unbolt the distributor cap (2 x 7mm head captive bolts). Disconnect the main coil lead from the coil and lift the cap/leads off.

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Disconnect the battery, undo the clamp (13mm socket), lift the battery out, then undo the two 8mm head bolts that hold the air cleaner assembly to the side of the battery box.

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The air filter pipe is held to the throttle body by a special clamp. You can undo it by levering under the edge. The back of the air box is a push fit behind the headlamp. The complete air box will then lift out.

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Coil and mounting bracket now. Disconnect the hoses with a pair of mole grips or pliers, disconnect the two temperature senders, and unplug the coil. Undo the 2 x 10mm bolts and the coil and bracket will lift out.

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Rear left-hand side of the head, disconnect the bleed pipe.

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Two breather pipes at the rear of the rocker cover. Disconnect them so that there is one pipe left on and one not - this will prevent you from accidentally connecting them wrong.

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Undo the 15 x 8mm head bolts (they are all the same), then remove the rocker cover and gasket.

You will now be looking at the camshaft assembly.

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The camshaft sprockets now have to be removed. Both are the same, and are marked for whichever camshaft they are fitted to (inlet or exhaust). There are two roll pin slots for each camshaft - I just mark them for where they came off. The cams have two flats on each one, and a 24mm spanner can be tapped on to hold them still while the sprocket bolts are undone - remove both sprockets.

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There's an 8mm head bolt below each camshaft that retains the timing rear case to the head - remove them. Undo the belt tensioner centre bolt (6mm allen key), and the 8mm head bolt on the backplate of the tensioner. Remove the tensioner. There's also a tensioner spring, which has disappeared/not been fitted.

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Now to remove the camshaft housing top half. There are 26 x 10mm head bolts - all the same length. Undo them from the centre-out and progressively to prevent valve pressure from bending it. The cover will then lift off. There is no gasket between the two halves - just a thin sealant. Carefully remove it with a stanley blade or similar, and then lift both cams out of the housing.

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There is quite a collection of oil in the front of the camshaft housing. Put some lumps of tissue in there to soak it up.

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Now the inlet manifold, which is held by 7 x 13mm head nuts. Remove them and the manifold will lay back away from the engine with all wiring, throttle cable, and pipes still attached. The gasket is a thin rubber bead, remove it, clean the slot it was in, and check/clean the little bleed valve on the left-hand end (they gunk-up sometimes).

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3/8" extension bar will fit through the tubes of the manifold.

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Hydraulic lifters next - these will all be the same, but it's wise to put them back in the same holes they came out of, so lay them on a card in the right order. A magnetic pick-up tool is ideal for removing these - they are slippery and there's nowhere to grip them.

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Exhaust manifold now - the upper alternator bracket is in the way of one of the manifold nuts, so it has to be removed. 13mm head bolt and 15mm nut to disconnect the bracket from the alternator. The alternator will then pivot towards the front out of the way. There is a 13mm nut and a hidden 10mm head bolt to remove and the bracket will then come off.

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The exhaust manifold has 5 x 15mm nuts on studs. The studs usually come off with the nuts, and this is better as the manifold is held pretty rigid and will not pull away from the head when the nuts are undone. If any studs stay in, then you will either have to lock one nut against another to remove them, or release the exhaust lower mounting to move the manifold away from the head.

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The inner timing cover has to be tied away from the head. There's one 8mm head bolt at the back - close to the dipstick tube. You have to undo the dipstick tube bracket, move the tube out of the way, then undo the timing case bolt.

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Using a cable tie or similar - pull the timing inner case back far enough to clear the end of the cams. Be careful when doing this as the case can crack if you pull it too far.

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Finally the head bolts. There are 10 of them and they are E12 Torx. Remove them in the opposite pattern to the tightening sequence to prevent warping the head. The bolts are very long and go right down the engine block to a rail in the sump.

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The head is now ready to be lifted. It's likely to be stuck, so lever in a couple of places to release it and then lift the head off and inspect the damage. Any valves that are still open will be bent, so it's easy to spot which ones are damaged. In this instance all 16 valves are bent, but it's usually 8 or 10.

Residual coolant will have flooded the bores, so mop it up, they spray the bores with WD40 to prevent them from corroding.

Using a stanley blade or similar - remove all traces of head gasket from the block face. Take care not to damage the alloy of the block.

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Parts you will need. However many inlet and exhaust valves need replacing, a head gasket set, perhaps a new set of head bolts, a valve grinding tool and fine/coarse grinding paste. You will also need the correct type of valve spring compressor for this type of head (recessed valve springs)

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Now the fun bit - removing the valve assemblies and fitting the new ones :(

position the foot of the compressor on the bent valve (it will have to be at the angle shown)

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The opposite end of the compressor has to sit square on the top valve seat-

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Wind the compressor in until you feel it start to tension, then tap the end with a hammer to release the collet grip on the top of the valve stem. You will most likely feel it pop and then proceed to wind the compressor in until there's enough room to pick the two collet halves out with a small screwdriver.

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Once the two collet halves are out - undo the compressor until it can be removed. Then lift out the spring top and spring, then the valve can be pulled out - you may need to tap it with a suitable drift.

What you should remove from each valve you need to replace.

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The valve stem seals are also the spring lower seats. They can be levered out at an angle through various holes in the head casting.

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The damaged valves and stem seals/seats.

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What you will be re-using - the springs, top seats, and collets. Clean them in petrol or similar and put them to one side.

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Inspect the valve guides for any damage (which is unlikely). You will be able to see them through the top of the inlet and exhaust ports, or where the valve has been removed. Any damage and the guide will have to replaced and reamed to fit the valve stem.

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The head should then be thoroughly cleaned.

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Note that the inlet valve is bigger than the exhaust.

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New stem seals first (they are all the same). A 17mm socket - dipped in grease will fit just perfectly on these. Centre the seal over the valve guide and tap it into place with a hammer or small mallet.

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Each new valve has now to be lapped in with coarse grinding paste first and then fine paste. Lightly oil the valve stem, apply a thin bead of coarse paste on the edge of the valve, then fit it in the head. Attach the grinding tool to the head of the valve and apply light pressure whilst rolling the tool to and fro between the hands. Occasionally lift the valve a few mm and then carry on for a few minutes until there is a grey band on the valve seat approximately 2-3mm wide. Clean the coarse paste off, apply the fine paste and do the same again. The valve is now ready to be fitted. Make sure that all grinding paste is removed from the head and new valve.

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Fitting the new valve -

Put the valve in the head, then the spring, and then the spring top. Put the compressor in the same position as for removal and wind it in until the valve stem is protruding about 10mm. I put grease on each collet halve - both to hold it to a small screwdriver while I locate it, and to keep the collet in place until the spring compressor is released. The collets have to go in - narrow end first, and the wider end has an inner lip which engages in the slot close to the top of the valve stem. Make sure the collet halves are correctly located and keep an eye on them as you release the compressor.

Once each valve is finished - tap the top of each valve stem with a suitable sized drift to make sure everything is located properly.

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The finished head - de-coked and ready to be refitted.

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The block face - cleaned and metal dowels fitted. The head gasket is marked so that you put in on the right way round/up

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Lay the head back on the block - making sure that it sits on both the dowels. Place the head bolts in position and tighten them as follows and in the sequence shown-

20nm, then 180-deg, then a second 180-deg

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Replace the lifters - clean them,check the oil holes in each one, dip them in fresh engine oil and then put them back in the head. They will slide in very smoothly.

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There are new camshaft oil seals in the gasket set so remove the old ones (you will have to remove the rotor arm (8mm bolt), clean the ends of the cams with wire wool or 1200 wet/dry, grease the lands, and then put the new seals on and replace the rotor arm.

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Put a thin film of oil on the camshaft guides, the camshaft lobes, and the camshaft bearing surfaces.

Lay the cams in the head - the one with the rotor arm on at the back. Make sure the seals are correctly located.

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The top housing can now be fitted. There is no gasket here - just sealing compound. I use torque seal or threadlock. A very thin film of it on one face, and then bolt the housing back down. Tighten the bolts progressively and from the centre outwards. There's no neutral position on the cams, so some valves will be pushed open as you tighten the cover back down. There is no risk of the valves touching the pistons as they are all mid-way down the bores.

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Replace the 3 timing rear cover bolts, then the timing belt tensioner (leave the bolts loose though), then camshaft sprockets - using the 24mm spanner method. Replace the inlet and exhaust manifolds (new gaskets in the kit), coil, and any pipework/wiring you had previously disconnected or removed.

New rocker cover gasket - it's marked to go on a certain way, then bolt the rocker cover back on.

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The distributor cap has 4 x alloy pillars inside which tend to get a white scale on them. This can be removed with a small screwdriver, then rinse the cap out with WD40.

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Replace the air box (use a pair of pliers to close the clip on the throttle body), then the battery.

Remove the spark plugs from the head.

The cams now have to be put in the correct timing position prior to fitting the new timing belt.

As you can see - viewed from the drivers side wing - the inlet cam on the left with the word 'inlet' on the right, and the exhaust cam with the word 'exhaust' in line with it. There are also 4 x slots in the sprockets and with a traight edge - all 4 should line up straight across the two camshaft sprocket bolt heads.

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Feed the new timing belt through the gap in the engine mounting. raise the engine and replace the two mounting bolts.

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Put the belt on the crank sprocket first and wedge it in place with a bit of olded cardborad or similar to prevent it jumping off the teeth. Feed the belt up the right-hand side first and onto the exhaust cam sprocket - making sure there is no slack in the belt, then across top the inlet cam sprocket - again making sure there is no slack. Remove the 8mm head bolt on the tensioner backplate and move the tensioner as far as it will go towards the back of the engine. Wrap the timing belt around it and then over the water pump sprocket. Apply finger pressure to the tensioner and push it towards the centre of the engine, attach the spring and replace the bolt. Medium tighten the bolt and the centre allen bolt on the tensioner. Put the crankshaft bolt back in the sprocket and rotate the engine two turns clockwise.

Check the timing marks all line up, re-tension the belt, and tighten the two bolts.

The timing belt is now tensioned correctly and the rest of the engine can be reassembled. Remove the crank bolt, replace both timing covers (bottom one first), Crankshaft pulley, alternator belt, PAS tensioner wheel, PAS belt (rotate the tensioner anti-clockwise), fit the belt, then release the tensioner.

Inner arch cover, road wheel, and lower the vehicle back to the ground. Open both cooling system bleed screws - one on the top heater hose, and the other on the metal section of the radiator hose - under the distributor cap. Disconnect the coil lead.

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Slowly fill the cooling system - keeping an eye on the bleed screws. When water starts to come out of them, tighten them up. You now need to fill the hydraulic lifters in the head. They rely on engine oil pressure, so with the plugs out and coil lead disconnected, spin the engine a few times to get the pressure up. Replace the plugs, attach the leads - locating the leads in the guides at the sides of plug caps 2, 3, and 4. Then replace the cover and reconnect the coil lead. Start the engine - it might take a few spins to get it going, but once running, leave it to idle. Smoke and steam will come off of various parts of the engine due to your greasy hands all over various bits of it. Keep an eye on the water level in the header tank - bleed the system a few times and keep an eye on the temperature guage. Turn the heater on inside the vehicle and feel for hot air coming out of it. Once it does - it's fairly safe to assume that the cooling system has been bled properly. Allow the engine to idle for as long as it takes for the cooling fan to start - watch out for any leaks. You must take care for the first couple of hundred miles or so - don't over rev the engine or put excessive strain on it. The various components need to settle in with the effects of engine heat/being removed.

There are two types of timing belt tensioner - manual and automatic. You need to know which one you have in order to get the correct timing belt (they are different). The one shown in this thread is the manual type.

Don't over-tighten the camshaft cover bolts. If you do - the cams will lock-up and will not turn.

I'll add the torque figures when my AutoData programme decides to work :rtfm:

Les. :

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