Rousing a Hibernating Engine

So far, we have helped a reader fix the braking and fuel systems of a 1970 Mustang. Now we tackle the power plant, step by step

Editor's Note: From time to time, Ted Welch will answer questions from readers about restoring old vehicles. This is the second of a two-part column. Part 1 appeared in February (see BW Online, 2/23/06, "Waking Up a Sleeping Beauty").

Let's look at some steps needed to wake up a sleepy old engine. On just about any valved engine, some of the valves will be in the opened position, even on a hydraulic-lifter engine. Any unsealed cylinder is susceptible to rust on its walls. Without any preparation, starting the engine now could lead to ring breakage or cylinder-wall scoring.

To prep the cylinders, pull all the plugs and wet down the cylinders with a good rust penetrator like Liquid Wrench by GUNK. You can use WD-40, but I have had great success with Liquid Wrench for this purpose. Wet down the cylinders a couple of times, allowing an hour or two between applications. Let the engine sit overnight before moving on to the next step.


  Then change the oil and filter. Select a light grade of oil like 10W-30 for this task. Look for whatever oil and filter you can get on sale, because you're going to change oil again after a few hours of operation (more on this later). At this point, remove the valve covers.

Due to its sitting around for so long, the engine will be dry and in need of lubrication. Hence, you'll want to get oil back into all the areas requiring lubrication before you try to start the engine. A pre-oiling tool inserted down the distributor shaft to the oil pump and driven by a drill motor will prime the oiling system in the same manner an engine does when it's running.

Of course, you'll need to remove the distributor to accomplish this goal. Because you cannot rotate the engine at this point, just pull the distributor and worry about setting up the timing later -- it's not that difficult. You can buy a priming tool from almost any auto-parts house, or you can try the Web sites and Set the drill motor to turn in the same direction as the distributor -- otherwise the pump won't pick up and move the oil through the system properly.


  If you have an old distributor, you can remove the cam gear and strip out the points, then use it as a priming tool as well. This might be a good time to consider replacing the old point-type distributor with a modern high-energy electronic distributor. You'll find many advantages to going electronic -- afterward, you could use the old distributor as a primer, save the cost of a priming tool, and apply the savings to the new unit.

Back to the engine!

With the oil changed, valve covers off, and priming tool inserted, prime the engine until you see oil coming out at the pushrods at the rockers. This may take some time since you have to fill the new oil filler and the oil galleries. If you don't see oil in a couple of minutes, check your drill's rotation again to make sure you're turning the pump in the right direction. Once you see oil on the top end, go back to the cylinders and wet them down again with Liquid Wrench.

Now you're ready to rotate the engine by hand. With the plugs still out, use a breaker bar and socket on the damper bolt on the crankshaft end to turn the engine over. Work the breaker bar back and forth a few inches to test how free the engine is. If the engine feels free, give it a turn in the direction that it normally runs. Rotate the engine around half way, and wet the cylinders down again. Continue rotating the engine around in half turns, wetting down the cylinder with each turn.


  After you have rotated the engine four complete times, set the engine on the recommended timing mark for installing the distributor. Give the engine another oil prime with your priming tool, and install the distributor. See your engine manual for timing setup.

Replace the ignition wires with fresh parts, but do not attach the coil wire just yet. If you're reusing your old distributor, replace the points, condenser, cap, and rotor with new parts. Do not use any of the old parts -- wire insulation breaks down over time, and oxidation affects the contact points. Using new parts reduces troubleshooting and increases the level of success in getting the engine started in the least amount of time. Plus, it will make the engine run more reliably on a daily basis.

Change the valve-cover gaskets, and reinstall the covers. Change the PVC valve and all vacuum lines on the engine. Replace any rubber fuel line between the fuel pump and carburetor: You don't want a fire on startup -- or any other time. Replace the battery with one that meets the cold-crank amp requirement for your engine.


  Check to see if there's water in the engine. If not, top off the radiator and overflow tank, and inspect your hoses. You'll want to replace all the cooling and heater hoses before you start driving the car, but at this point, if they appear sound, use them -- more on the cooling system later on.

With fuel lines attached, the plugs still out, and a new battery installed, it's time to turn the engine over with the starter. Before you start, wet down the cylinders again one last time. The "plugs out" start will prime the fuel system and help promote oiling in the engine before you go for an engine start. Make sure you take this step with the plugs out -- you don't want to crank against compression at this point.

Crank the engine in 15-to-20-second intervals about five or six times. Once you see fuel at the carburetor, it's time to gap your plugs and install them. Attach the coil wire, and check the engine over to make sure the belts are tight and there are no fuel, oil, or water leaks. If you have power steering, make sure the fluid tank is topped off.


  Even the best laid plans can go awry, so have a chemical-fire extinguisher at the ready, one large enough to extinguish an engine fire, about 5 pounds. Engine fires have destroyed many a garage and home. I always have a heavy wool army blanket soaked with water to use as a first response to a fire -- it makes more sense than dousing your engine with chemical fire retardant to put out a small flare-up or backfire flame.

Now, start the engine. Given the timing is correct and you have fuel, the engine should start and run. Once the engine fires, you'll see a lot of smoke, but that's OK. Piston rings will take some time to loosen up and reseat, and valve seals will need time to begin sealing up as oil returns to the top end. Allow the engine to warm up for a few minutes, and then maintain between 800 to 1,000 rotations per minute (rpm). Refrain from revving the engine up and down, and don't go more than 1,000 rpm until the engine has run for about half an hour.

Let's hope that, during the run up period, nothing starts to leak, burst, or snap. Old belts and hoses will need replacing. The cooling system will require flushing and recharging with a fresh coolant/water mix. Personally, I would change the water pump and thermostat when you do your hoses. These parts always seem to go in the followings days, and dependability is the justification for making these repairs.


  At this point, if you feel the car is roadworthy, drive it around the neighborhood for a few laps, then head off to the lube shop or your favorite garage for a full fluid change out and chassis lube. Change the transmission, differential, and engine oils. Replace the air, fuel, and transmission filters. Lube the driveline, steering, control arm, and ball joints.

Automatic transmissions suffer from long storage periods and sometimes do not work properly until rubber seals are lubed back up. These seals can harden without the frequent lubrication of transmission fluid. K&W offers a transmission sealant that contains naphtha, which helps to soften hard seals and allows them to close up. I am not a big fan of additives, but the K&W product works well when used to restore seal pliability.

As you continue with your restoration, you will run across other areas of the car that long-term storage has taken its toll on. Nothing is worse for a vehicle than sitting around unused. As far as the engine goes, the more you drive the car, the better it will run.

I hope this information helps you and that your restoration project is a huge success!

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