Duratec Camshaft set-up

Finding TDC.....First you will need install the timing disc, I did this by drilling it out to the diameter of the front pulley bolt, then cut a slot in the disc. As per Pic:2, make a pointer using a bit of wire (in my case coat-hanger) and attach it to a bolt somewhere convenient. Next set the timing disc to indicate zero on the pointer when the crank is at TDC. The trick to finding true TDC, lift is dwell. This is a period (about 10°) either side of TDC when the piston ‘hovers’ at the top of its stroke. What this means is that you don’t try to find the exact position of TDC using one reading on the dial gauge. To find ‘true’ TDC :- Set up your dial gauge indicator so that it is touching the top of the piston, if the head is still on you will have to make up an extension (Pic:3) to reach through the spark plug hole (coat-hanger again). Turn the crank until the piston is at the top of its stroke and set the timing disc to zero. You will find that there is a dwell period of approx. 10 degrees where the piston is at its maximum height. True TDC position is at the centre of this dwell period. Rotate the crankshaft and stop at a figure just before TDC, approx. 0.2mm on the dial gauge. Record the figure on the timing disc from the pointer. Now rotate the crankshaft and stop at the same figure (0.2mm) after TDC. Record the figure on the timing disc again. True TDC is positioned in the middle of these two figures. The TDC position can be calculated by adding the two figures together and dividing by two. Adjust the timing disc pointer so that it reads zero at true TDC.

1: Dial-gauge, magnetic holder and coat-hanger extensions	2: Timing Disc and coat-hanger pointer	3: Finding TDC using dial-gauge
4: Parallel slots with file "TDC setting"	5: Finding full lift on Exh-Valve	6: 110 degrees on Exhaust
7: Inlet lift	8: Inlet from back	9: Dialled-in

Cam Installation.

Install your camshafts into your head with the pistons all down in the cylinders, but with the No:1 piston on the way up. Lubricate all rotating surfaces with cam-lube. Torque up cam bearing caps. Set the Cams to their Top Dead Centre (TDC) "set up position" as per the slots at the rear of the cams (Pic:4). Slots should be horizontal to the head surface with room for flat piece of metal (in my case a file). Rotate engine (always clockwise) so No:1 piston comes to TDC on the timing disc. Install cam-chain, tensioner, guides, vernier sprockets etc with cams as per Pic:4. This is pretty close to the correct set-up and the engine should turn freely with all bolts tightened.

Camshaft Timing

As with the crankshaft, there will be a dwell period where the valve is at full lift. True full lift is at the centre of this dwell period. Set the dial gauge so that it will read the lift of the exhaust valve on number one cylinder (measured on the bucket). Have your timing figures for your cams to hand. In the case of my 2.3 Duratec with 280° Raceline cams, the settings are: No.1 Exhaust valve fully open 110° before TDC (i.e. ex-cam on No.1 at full lift). No.1 Inlet valve is fully open 106° after TDC.Rotate the crank clockwise until the exhaust valve of number one cylinder is just off full lift position (say 0.15mm). Record the figure on the timing disc from the pointer. Then continue to rotate the crank clockwise until the valve has fully opened and then closed by the same distance as previously used (0.15mm). Read the degree figure on the timing disc again (Pic:6). The position of full lift is the middle of these two figures.Adjust the vernier sprocket so that the reading on the crank is correct according to the manufacturers figure. Some repetition will be required to get the correct setting.

Once the Exhaust cam is dialed in, do the same for the inlet camshaft (Pic:7 & 8). Finally check everything all over again, TDC, Exhaust lift, Inlet lift. It is time consuming, but do it once properly and it will never have to be done again (until you upgrade your camshafts again.)… Once the Cams are dialed in, they should look like Pic:8, which is only a few degrees different from the initial "slot TDC" setting. Engine Start Up Before starting the engine, turn the engine over by hand to ensure that it turns freely. Prime the oil system and check that everything is set to ensure that the engine starts straight away. The engine must not be turned over for any length of time on the starter.Once started, do not allow the engine to idle for the first 20 minutes and keep the revs to a minimum of 2500 rpm. This will ensure adequate lubrication of the cam and followers and reduce the contact force between the cam and follower. If any adjustments need to be made within the first 20 minutes, then shut the engine down. DO NOT ALLOW THE ENGINE TO IDLE.

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