Before performing the timing chain replacement you have to check how much it is stretched. To measure the stretch, use a gauge. This is the foto of it.
In EP6 engine the gauge is to be screwed in instead of the tensioner. First, screw an internal pin out of the gauge, then grip the gauge and screw it into a threaded hole until tight. The internal pin is to be screwed in place the same way with only difference that it need not be inserted to the max. Just push and hold it with fingers. You can then measure dimensions with caliper or other standard instrument. The normal timing chain length must be up to 73 mm on EP6 engine and 71 mm on EP6DT Turbo engine.
It is much better to replace timing chain on Peugeot 308 with EP6 engine when a car is lifted. If there is no lifting-jack hoist, then the car should be put on jack stands, so that you could unbolt the right engine mounting support and set the flywheel timing mark which is in the bottom of the engine. You will see this in the photo.
Peugeot 308 Turbo is taken for illustrative purposes, but it is worth saying that non-turbo engine can be fixed even easier. It has almost an identical arrangement except perhaps a different valve cover; and a phase shift device is found on the exhaust camshaft.
You will need the Engine Locking and Timing tool kit for Peugeot
- Wrenches, a small one (1/4) and a big one (1/2)
- 18 mm A/F for the crankshaft pulley bolt
- 10 mm A/F for unwinding of the valve cover
- 8 mm A/F for unwinding of the upper damper
- 27 mm A/F for the chain tensioner
- Е16 for the camshaft bolts
- Torx T40 for unwinding of the lower dampers
- Torx T30 for removing a throttle valve module (for non-turbo model)
- 16 mm A/F spanner for unbolting motor mount connection
- Unbolt the air filter, slide it out and take it aside.
- Loosen all the screws that hold the valve cover, remove the cover. Take a wrench and an 18 mm A/F socket. Turn the crankshaft pulley. Align the camshafts roughly to set a timing mark at the bottom. Note: if you have missed the timing mark, do not turn the shaft anti-clockwise. Just make two more turns forward for proper positioning of the shaft.
- Remove shields under the engine, if there are any.
- Jack up or lift the car up using a hoist to place the lower mark into the hole.
- The right wheel as well as the locker must be removed.
- If you do not use a car lift, you should put something under the engine protecting plate. It can be a pallet or even a stump; you may lower both the car and the engine on it in order to remove the right engine support assembly.
- Install a special tool (the upper one) for setting marks on camshafts.
- Remove the alternator belt.
- Unscrew the pump roller; it is secured by three 10 mm bolts.
- Then dismount the upper damper and the chain tensioner.
- Remove the crank pulley.
- Unwind the 18 mm bolt that holds down the lower timing sprocket seat.
- Take this seat out of the oil seal. (the seal is to be replaced by a new one)
- Remove the lower dampers. To do that you should unwind 3 bolts, as shown in the photo.
- Take out the oil dipstick. It is inside of the block and is coming through the chain damper.
- Pull the chain up together with dampers and the lower sprocket.
- Install everything back in reverse order of removal and set timing marks.
Note: For maintaining the valvetrain system all the pistons are located in the same intermediate position, i.e. dead center.
First, before the installation you need to arrange chain and dampers as shown in the photo. And only after that the valvetrain should be lowered to its seat.
Before installing the valvetrain system back to its location, you must degrease the sprocket and the crankshaft hub.
According to manufacturing plant regulations the following new spare parts are to be installed when replacing the timing chain:
- Timing chain
- Chain tensioner
- Dampers – 3 pcs
- New camshaft bolts
- Crankshaft sprocket hold down bolt
- Phase shifter or camshaft sprocket (1 or 2 depending on a model)
- Crankshaft sprocket
- Valve cover gasket
It is recommended to apply some threadlocker to the crankshaft sprocket bolt.
- Chain tensioner – 8.5 dNm
- 3 damper bolts – 2.5 dNm
- Crankshaft hub bolt – tightening torque: 5 dNm plus 180 degrees additional rotation
- 3 bolts of the belt and pulley system – 2.8 dNm
- Phase shifter bolt – tightening torque: 2 dNm plus 180 degrees additional rotation
- Camshaft sprocket bolt – tightening torque: 2 dNm plus 90 degrees additional rotation
Note: do not mix up phase shifters – the one on the inlet camshaft is marked as IN35, the other is on the exhaust camshaft and has the mark EX30.
Video on how to set timing marks on EP6 engine