These are connected to the battery and spark plug wire prior to use. Wear, inaccuracy and high maintenance have forced car manufacturers to abandon this system, replacing it with computers and individual ignition coils for every cylinder--and no points to wear out. A dwell meter is needed to properly adjust the dwell angle, which is done with the engine spinning on the starter motor or, on some engines, actually idling. If it does, loosen the bolt that secures your engine's distributor so you're able to rotate it. They should last as long as a set of points, 20,000 miles at least. A lesser timing light may not be able to process the signal and flash the strobe before the next signal comes in, so it figures 'too late' and just process the 'next' signal. My airhead is also having problems with my old snap-on timing light.
Lastly, you take the signal wire and clamp it directly to the Number 1 spark plug wire. Tuning the static or initial timing is achieved by simply twisting the distributor body in relation to the rotor. Loosen the bolt that secures the engine's distributor enough so that the distributor can be turned. If the number is not as specified then you may have a distributor mechanical advance problem. Once the static ignition setting and the ignition advancing mechanism in the distributor is correct, the air-fuel mixture can be tuned for full power and fuel efficiency.
It'll take some touch to get it right, so it helps to have someone to rev the engine, check the number, and twist the distributor. The high voltage now travels over to the distributor, where the rotor metes the high-voltage pulses out to the correct spark plug. To learn whether or not you need to adjust your timing, find the optimum timing number for your make and model and adjust if necessary. Similarly, a vacuum advance uses a rubber diaphragm to advance or retard the timing. 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.
Take out the spark plug for cylinder 1, then poke your long screwdriver down in the hole. Shopping online in the U. The first is the centrifugal advance. The proportion of time the distributor's cam keeps the points closed and open is referred to as dwell angle. Once that's loose, just rotate the distributor until the timing mark is in the right position and then re-tighten the bolt.
I took this to a recent Hudson meet and no one really knew how to hook up the clamps at the end of the two cables. Getting your timing light ready for action is breathtakingly simple. The simplest and least expensive timing lights fit into a basic pen shape. The 'dial back' timing lights process the signal, and use time between signals rpm's for 'when' to flash the strobe. And who doesn't want that? Cookies enable us to store information about your preferences and we use them to improve the functionality of our website and your experience when using it. Check the shop manual for your car.
Because of the time required to ignite the air-fuel mixture in the cylinder they need correctly advanced ignition timing to run properly. Modern engines use computer-controlled factory-preset self-adjusting ignition systems that never change their timing, have no moving parts and never need maintenance. Compare the two below 2,500 rpm. I believe it is working fine because that part has nothing to do with the light and is something its previous owner somehow managed to drop into the clamp assembly. Nonetheless, there are still plenty of older vehicles, outdoor power equipment, boats and tractors that need periodic adjustment or replacement.
My back up is a Snap On made about the time electricity was discovered, the type that plugs in between the plug wire and the plug. We used to joke that it took 3 people to set the timing on a car. The correct polarity is whichever connection gives the most retarded timing. Dave The one I use most is a cheap old style inductive light, plastic body, may be a Sun, the neighbors' kid ran it thru a fan on a running engine, cut the wires in several pieces, so I soldered and heat shrunk? All models of cars will have differing timing values, depending on the year it was manufactured and the variety of transmission used. Contamination will carbonize and become a resistance where there should be only metal-to-metal contact. You can easily find that on your Vehicle Emission Control Information Label located on the underside of the hood or along a fender well for vehicles built in the United States or in a service manual specific to your vehicle. Thus, at idle the number on the dial would represent your initial timing.
Loosen the clamp holding the distributor down and slightly rotate the body of the distributor to line up the timing marks. To learn how to use a timing light or timing gun, scroll down! So I pull the plug out of the cylinder head and left it dangling and voila! Therefore, disconnecting and plugging the vacuum advance allows you to accurately measure initial static timing. When you pull the trigger of the timing light with the engine running , each time the Number 1 plug fires, the timing light flashes a beam of light. The bike produces a good spark on both plugs when I check them against the cylinder head. Jay Safford is an automotive consultant and project manager in Lake Worth, Florida.