The four "strokes" in the 4-cycle engine refer to the process of intake, compression, power, and exhaust. The line or notch will point to the current degree mark. If the installation marks have disappeared, place a new installation mark on the timing belt before removing each part. Ignition timing is tough to understand, but easy to adjust and set. Once started, do not allow the engine to idle for the first 20 minutes and keep the revs to a minimum of 2500 rpm. Understand the ignition cycle. This will drop the pistons down in No.1 and No.4 cylinders and ensure there is no unwanted piston to valve contact when the camshafts are rotated without the timing belt installed. Start and let the engine idle. There probably is a picture somewhere of what the timing marks on the flywheel look like (BB, lines, triangle), but first, search the forums in the box on the left with the word 'timing'. The sequence in which this happens is very finely balanced, or "tuned," to provide maximum power and economy. If the timing mark is at 2 degrees or 10 degrees to the left (CCW), the marks would be at 1:26 and 1:10, respectively. the line is to the LEFT of the keyway, looking at the front of the damper or engine. If timing specifications call for 10 degrees base timing BTDC, and the reference line is pointing to the 3rd degree mark, adjust timing. A few tips on how to get your timing marks correct on a 350 chevy. Ignition timing is when the distributor sends an electric spark into the engine to ignite the fuel. The light works as a strobe light and you'll see the timing marks stationary. Direct the timing light on the timing marks. The engine must not be turned over for any length of time on the starter. This fuel ignition is what powers the car. Downside is the timing marks are now useless. A few tips on how to get your timing marks correct on a 350 chevy. The timing marks and running engine won’t line up as you are finding. The timing of the ignition refers to the point between the compression and the power strokes at which the spark plug fires, creating the combustion that results in your horsepower, forcing the piston down into the cylinder. Read through a few of the timing threads the search returns, and you will probably find the information you need. EM–20 ENGINE MECHANICAL – TIMING BELT MARKS ON TIMING BELT Check that there are four installation marks on the timing belt by turning the crankshaft pulley as shown in the illustration. factory timing alignment marks chain sets & belt drives gm ohv v8 250 (4.1ltr) gm chevrolet v8 sb 305, 327, 350, 400 petrol engine gm v8 350 (5.7l) diesel gm v8 ohv 368, 425 oldsmobile v8 ohv 260, 307, 350, 403 renault toyota 4 cyl ohv & ohc 2tg, 3tc, 3k-c, 4k-c, 4k-e toyota 3k-4k The pre-1969 damper has the TDC line on the outer ring at the 2:30 o’clock position- or 2º before the keyway centerline- i.e. By moving the firing order of the spark plug wires in the distributor and readjusting the timing by moving the distributor until the engine runs smooth will make it work. This will ensure adequate lubrication of the cam and followers and reduce … Ever do a timing belt or chain and you go to line up the timing marks and find that they’re just a little bit off? 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