How to Set the Timing on a Slant Sixby Robert Bayly
The Chrysler Corporation slant-six engine was produced from 1960 until 1987. 170- and 198-cubic-inch versions were produced, but the 225-cubic-inch version is by far the most common. It could be found in almost every Dodge and Plymouth passenger car and Dodge truck. Its important to have the timing on your slant-six engine set to the proper specification. This will ensure optimal performance and gas mileage. Having the timing set too late -- retarded -- will result in poor acceleration and mileage because the fuel is not being completely burned. Having the timing set too early -- advanced -- can cause the engine to clatter under acceleration, which can damage the engine. As they say, "Timing is everything."
Run the engine until it reaches operating temperature. Park the vehicle on a level, paved surface and set the parking brake. Turn off the engine.
Find the timing tab on the driver's side of the timing chain cover. It has numbers stamped in it that read -- in a clockwise direction -- "Before 15-10-5-0-5-10 After." Your specific tab may have different numbers but they will all read from "Before" to "After."
Look for the timing notch in the crankshaft pulley. If you can't see it, bump the starter a couple of times to move the pulley, and then turn the key off. When you can see the notch, rub some chalk into it to make it more visible when you shine the timing light on it.
Remove the rubber hose from the vacuum distributor vacuum advance and plug it with the tip of a pencil. If your engine is 1982 or later and has an EGR valve, remove the rubber hose from it and plug it with a pencil.
Use a wrench to loosen the distributor hold-down bolt. Loosen it just enough so that when you try to turn the distributor it is hard to turn. Otherwise, it will turn by itself when you start the engine.
Hook up the timing light to the engine with the spark plug pick-up clipped over the No. 1 spark plug wire, which is the first wire at the front of the engine. The power wires are clipped to the battery. The red lead goes on the positive "+" terminal. The black one on the negative "-" terminal.
Make sure the timing light wires are clear of the fan, belts, and pulleys. Start the engine and aim the timing light at the timing tab. You will see the notch in the pulley appear to float next to a number on the timing tab. Turn the distributor to make the notch line up with the timing value specific to your engine. This information is usually on a sticker by the radiator support. A typical setting for 1982 and later engines is 12 degrees before top-dead-center. 1960's engines are set at top-dead-center. Its very important to find the specific setting for your year engine.
Turn off the engine. Tighten the distributor hold-down bolt. Unplug the vacuum hose and hook it back up to the distributor. Unplug the EGR hose -- if equipped -- and hook it back up to the EGR valve. Disconnect the timing light.
- "Chiltons Truck and Van Repair Manual 1979 through 1986"; Chilton; 1986
Things You'll Need
- Shop rags
- Wrench set
- Timing light
Robert Bayly, based in Apple Valley, California, began writing in 2010, his "how to" articles can be found on eHow. With more than 15 years in the auto industry, Bayly has been an auto and diesel mechanic, service writer and parts manager. He received certificates from Pontiac (parts system), Cat Diesel (engine service), Saab and Fiat (parts- warranty system).