If you are pulling your first classic out of a junk-covered barn, chopping it out of the undergrowth, or it has simply been sitting in a relative’s garage for years chances are you are not going to be able to just pop the key in the ignition and drive off. Do not be discouraged, though; look under the hood before starting an old engine. If all the fundamental components are in place, it is not as hard as you might think to get an old engine to sputter back to life.
If you are a buyer then its buyer beware if you are hoping to find a car that will run again because the oldest one in the book is, “It ran when I parked it.” Do not be like the ignorant person on TV pouring gasoline down the carburetor. Pouring gasoline down a carburetor works great for a flame fueled backfire or contaminating the engine oil with gas, but it is a bad idea and starting an old engine this way is doubtful.
There are a few essential supplies that everyone needs for a “will it run” adventure. Always make sure you have a fully charged battery and an external fuel source in the form of a jerry can, bottle or jug – a way to provide 12v power to the starter and ignition. Now, she may not be ready to run and move under her own power just yet, but at the very least you will have somewhere to start.
Here are a number of simple steps you can take to make sure your engine is ready to fire up after sitting for an extended period before you start to spend money on rebuilding or replacing drive train components like the carburetor or alternator, and even before diving into the transmission or differential.
Inspect Before Starting an Old Engine
After you have gained access to everything under the hood and have a clear area to work, make sure the engine is whole and has all the basic sources of air, fuel and spark that are needed for ignition. When you have accounted for all your accessories and drive belts, remove the air cleaner so you can check and clear the carb/throttle-body of any debris.
Rodents and insects like to make air intakes and vacuum hoses their homes, so make sure there is no debris resting on top of or in the carburetor or throttle body. If you find any heavy build up in the recesses or barrels of the carburetor or throttle body, you may want to consider removing the intake manifold and checking the intake runners as well. If the vehicle was stored with the air cleaner assembly on, or at least a rag over the intake, you should be okay
The newer your car the more electrical components you will find under the hood, but even old engines can have electrical problems. If all the mechanical parts seem to be working properly and you still cannot start your old engine, you may have an electrical problem.
The easiest problem to diagnose and fix is the battery. Car batteries are made up of a lead-acid or lead-calcium system that converts chemical energy into electrical energy. Batteries go through a recharging cycle when the alternator sends a current to the battery’s internal plates and back into the electrolyte mixture inside the battery.
When a battery is not being used, the chemical reaction in the battery breaks down and causes it to lose its energy. If the battery sits long enough it will be ineffective for starting up the engine. If the battery is not that old, and it is a maintenance free model, you may be able to add a little distilled water to it to see if you can generate the charge. If it has been sitting unused for a long time, it is best to install a new one.
In addition to checking the battery, inspect the ignition coil and coil wire. Use a multimeter on the coil to see if the resistance reading matches the recommendation for your vehicle. If it does not, then the coil may be bad. If the coil and its wiring work, use a current reader to see the starter motor is receiving a current. Corrosion or bad wiring can inhibit the starter motor and prevent the engine from firing up.
If your electrical systems are working and the car still will not start, you will need to try a different approach.
Manually Turn Over Engine
Next, make sure that the engine is “free” and will turn over. If the engine has been sitting for a long time and you are not sure when it was last running, you will want to remove each spark plug and squirt a tablespoon or so of “Marvel Mystery Oil,” engine oil or down each hole. If you feel that the cylinders have more rust, then you can use ATF (automatic transmission fluid) which is an “old school” mechanic trick. This will ensure that the cylinder walls and piston rings are coated and lubricated.
To ensure that the engine is free, use a ½ in. drive ratchet or breaker bar to rotate the engine over by hand using the crank shaft pulley bolt. As you do this, listen for any grinding, clunking, or scraping noises. Be sure not to confuse this with the puff or hiss of air compression being released, which is normal and will also push out most of the oil you used to lubricate the cylinders.
When an engine is old or has been sitting unused for a long time the internal components are going to be less likely get going. You can liken it to Newton’s first law where he said that an object at rest tends to stay at rest. This just means the engine will need a little coaxing and more oil or ATF fluid and let soak in. Since the engine has not had any oil running through it in a while it will need to be lubricated. You can do this using a product called Marvel Mystery Oil to lubricate the cylinders, pistons, and rings. You can do this by taking out the spark plugs and pouring a small amount of oil directly into the cylinders. The plugs will need to be replaced anyway.
There are two separate ways to get the engine to turn over at this point. In some cars you may be able to turn the engine over using a socket wrench on the crankshaft nut or you could hook up a battery to the ignition. Any oil that is in the cylinders will come out when you do this. If the engine turns over after you crank it then it may start up once the spark plugs are replaced.
Getting the engine to turnover is a good sign, and if you have already corrected some other problem areas then the above suggestion may be all you need. But even if everything is working properly with the engine there still are several other factors that you need to inspect before you can get the engine running for good
Lubrication Before Starting an Old Engine
Using a catch bucket, remove the engine oil drain plug, then drain and fill the engine with fresh oil. When changing the oil also do not forget to replace the oil filter. We also recommend filling the new filter with oil before installing on engine and use an oil with a zinc additive to help minimize wear when restarting.
Depending on what was used as coolant and how long the vehicle has been sitting, there may be bits of rust and other gunk in the cooling system. You can run the engine for a brief period (1-2 mins) depending on the outside temperature without the radiator hoses or cooling system connected, but it is never a bad idea to drain and flush the radiator and engine to the best of your abilities beforehand.
Ignition and Wires
If the engine ran before your project was parked and was not scavenged for parts or messed with afterwards, your ignition timing may be acceptable. However, you will need to make sure that you still have power to the ignition, and that it is generating spark. It is a good idea to remove your distributor cap and check for moisture, rust or debris and verify the rotor position. Cleaning the inside of the cap and scrape a residue off the cap nodes and rotor as well as the cleaning of the points contacts if the car has a standard ignition. This is also a suitable time to inspect the spark plug wires and confirm that the wires are in the correct firing order on the distributor. Missing this has caused me some frustrating hours on why the engine did not start or would not run properly.
If you decide to verify base timing before attempting the start-up, you will need to complete a few extra steps.
Ignition Timing
With the #1 spark plug and distributor cap removed, rotate the engine over by hand. With your thumb over the spark plug hole, continue rotating until you feel air pushing out from the #1 cylinder and the zero mark on the engine’s timing pointer is lined up with the mark on your harmonic balancer.
At this point you will have reached TDC (top dead center) on the compression stroke for cylinder #1 and your rotor should be “pointing” towards cylinder #1. Make sure you know the firing order of your engine and can verify this. Fine tuning the timing can be done later.
Timing belts, or chains, are the part of your engine that keeps the camshaft, distributor, crankshaft, and pistons coordinated. When the timing belt breaks or is damaged it can keep the engine from starting up. Most timing belts will last about 60,000 miles (96,561 kilometers) but if your engine has been sitting for a long time it might be a good idea to inspect it.
Many cars use reinforced rubber belts, but older cars and many newer luxury cars still use metal chains. In either case, a broken timing belt (or chain) will inhibit your engine from starting.
Although it may take only a few minutes to slip the belt on, getting to the belt might not be all that easy. It is likely you will have to take off multiple hoses, move electrical wiring and remove other engine components to gain access to it. Once you can access the belt, you will have to make sure to align the crankshaft and camshaft markings and ensure the number one piston is at top dead center (TDC). If you do not get this exactly right, you can throw the entire engine off its timing and cause some serious internal damage when all those metal parts start crashing into each other.
Changing the timing belt is not for everyone. It requires a high level of skill, and in some cases, it might even require taking off an engine mount to gain full access while suspending part of the engine as you work on it. If your timing belt or chain is old, stretched, worn, or broken though, you will need to replace it to get your engine started. Consider taking it to a mechanic if you do not have the tools and skill required to replace it.
Vacuum Hoses Inspection and Replacement
Once your engine is free and able to rotate by hand, verify that the vacuum hoses and lines are connected where they should be and clear of debris. While all you really need for a first start is fuel and spark, you do not want to circulate gunk or debris through the engines air of fuel system.
This step is not entirely necessary if you only plan to get the engine to “fire up,” but if you want to run it for any measurable amount of time. Your engine creates a vacuum when the intake valve is partially closed in the intake manifold. The vacuum is then used to help power other components on the car. It may help reduce your effort in pressing down the brake pedal or, in older cars, it may even power the windshield wipers. If enough vacuum hoses have leaks, or you have one big leak, it may keep your old engine from starting.
In newer cars, some vacuum leaks can cause engine sensors to report incorrect readings to the engine’s computer system. When this happens, even minor leaks could keep your engine from starting. A few trouble spots for vacuum leaks may be the throttle body, the manifold seals, the positive crankcase ventilation (PCV) valve or the PCV hose. Although those may be some trouble spots, there are numerous vacuum hoses in each car.
When the engine sits for a long time, the hoses can deteriorate and develop cracks. A few small leaks will not keep your car from starting but large leaks, or too many small ones, may be too much. There are several ways to determine if you have a vacuum leak, but the most effective is using a smoke generator. This smoke-out tool generates smoke in the engine so you can see where the vacuum leaks are coming from in each hose.
This tool is expensive and usually used by professionals, so it may be a better idea to locate a diagram of your engine’s vacuum hoses and replace them all instead. Replacing all the hoses in an old engine is not a bad idea, considering you could spend a lot of time trying to track down a leak and you will be replacing several hoses either way.
Fuel
Another major factor that causes old engines not to start is old gas. Gas is a highly refined product that vaporizes and combusts easily. The same chemicals that give gas these properties are also the ones that allow it to evaporate over time and cause the gas to lose its ability to ignite easily. In addition to evaporation, a process called oxidation can occur, when chemicals in the gas mix with oxygen. This produces deposits in the gas that can clog fuel lines, fuel filters, the carburetor and fuel injectors. Gasoline that has ethanol in it also tends to draw moisture out of the air and can contaminate the gas as well.
If the engine has been sitting for years, any gas in the tank or fuel lines is bad or contaminated. You will want to disconnect the main fuel line from the carburetor to avoid pumping bad gas through the fuel system.
You can run carbureted engines briefly using a water bottle with holes poked in the cap to manually supply the carburetor.
If you plan to let the engine idle, you will want to rig up fuel line from the carburetor to a gravity fed source like a large bottle, jug or jerry can. You do not need to replace fuel lines or a gas tank for an initial test start.
Coolant/Anti-freeze
In addition to replacing the old gas, the antifreeze will need to be replaced as well. Antifreeze breaks down over time and forms acids that can hurt your engine. Some people recommend using water, instead of coolant, when you are first starting the engine. If there is a problem with your head gasket, you do not want antifreeze (or water) leaking into the cylinders.
Power
All you really need to get the car started is a new battery with a full charge to ensure that it has the cranking power to turn the starter can spin the old engine fast and long enough to start. Be sure to check all the wire connections and ground straps, and clean as necessary to remove any corrosion.
Now, with a solid 12v source to your starter/ignition, a clean ground, new fluids, base timing set, your gravity fed fuel system and all your plugs and wires hooked back up, you are ready to attempt your first start!
The Attempt to Start
Before you attempt to start the engine, make sure that the car is in neutral, and you have the tires chalked.
It may take many cranks for compression to build and for combustion to occur; do not be discouraged if it takes more than a few cranks. You may want to hold a rag over the carb to “choke” the engine for initial ignition.
Adjust the airflow and fuel, feathering the throttle once ignition is achieved. Carefully spray or two of starting fluid or a squirt of fuel directly into the carburetor or throttle body may also help successful combustion and keep the engine running for the first few seconds.
Starter fluid is more volatile and works better than gasoline, plus it is a lot safer to use.
Starting fluid goes a long way and lasts a longtime. Some types of starter fluid can last 20 years and contain upper cylinder lubricants good for an old engine that sat for an extended period.
Finally
Once the engine is running and you hear no loud knocking, clanking, or pinging, it is likely that the engine is healthy enough to at least move the vehicle under its own power. If you are brave, at this point you may attempt to drive it a few feet or so from its early grave, but do not get hasty! Learn all you can about your project, do not take any shortcuts and do not give up. You have a long journey ahead of you!
What if u do hear clanging and pinging
Matt:
You will need to do bit of investigating before removing the engine as it may be the valves are not properly adjusted. See if you can locate the source of the clanging. The ping may also mean that the engine is not properly timed and pre-detonating. If the sounds are coming from the bottom of the engine, then the problem may be more serious.
Wow, this post is pleasant, my sister is analyzing these kinds of things,
thus I am going to tell her.