Join Date: Mar 2001
Location: Peoples Republic of Vermont
From the first semester of Automotive Technology, circa 1973...
Step 1 - Cranking Compression Test. This will establish the engines basic ability to run (properly). It is performed when the engine is "warm" by removing all spark plugs, grounding the coil wire, blocking the throttle wide open, making sure the battery is fully charged (connecting a battery charger throughout the test helps) and cranking the engine a minimum of 6 compression cycles. Record the readings. Repeat the test after inserting 2oz of fresh engine oil into the cylinders. The difference between highest and lowest cylinder should not exceed 15%. If it does, you have an issue that needs to be corrected before the engine has a chance of running smoothly.
Step 2 - Assuming you've passed Step 1, the next step is to verify the integrity of all IGNITION COMPONENTS. Use your ohmmeter to check resistance of the coil primary and secondary, ignition high-tension wires and spark plugs. Check the distributor cap for carbon-tracking, cracks or worn/corroded contacts. Check the distributor rotor as well. Disconnect and test the condenser and, finally, inspect the breaker points for wear/pitting, proper gap/dwell and the condition of the rubbing block. Finally, set the ignition timing to specification.
Step 3 - Assuming you've passed or fixed issues in Step 2, move on to the fuel system. Check the condition of all vacuum connections, hoses and operation of the PCV valve. Inspect and/or replace the fuel filter and check the fuel for contaminants. Adjust the carburetor choke, idle mixture and curb idle speed.
Step 4 - Check MANIFOLD VACUUM with a suitable gauge. Observe the needle reading/movement. It should be steady and, at or near sea level, should be around 20-21" hg.
Step 5 - Road Test.
What, me worry?
- Alfred E. Neuman