Editing Freeing a stuck engine (section)
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==Unsticking the "impossible"== The basics of unsticking any engine are the same. Fill it up with a fluid that will penetrate and lubricate the stuck surfaces. Remove or loosen any accessories that may be frozen up and causing the engine to be harder to turn over. Usually just loosening the belts will help with this. Start by turning the crank, even a small amount will - over time and with repetition - cause it to break loose. Or it will tell you that the engine is well and truly frozen up and needs to be disassembled for a proper rebuild. Even a degree of movement or a thousandths of an inch is a start in moving the engine's reciprocating assembly. Allow time for the penetrant to work and don't get impatient. ===Using penetrating fluids=== Using a fluid that will penetrate and lubricate is key. You need something that will penetrate, stay wet, and wick its way up into the smallest area. Ordinary motor oil will coat but penetrates at a very slow pace. Petroleum or mineral spirits will get into small places but will dry out over time. Paraffin will wick its way up or down a threaded bolt, but only when it is melted. Acids will eat their way through but can cause damage of its own and may be hard to control as well as dangerous to handle. Caustics are more of a slow burn and may require heat to work better, and are often harmful to aluminum/aluminum alloys. Water will penetrate, wet, and coat but has many limitations. Diesel fuel is a middle-of-the-road fluid that will creep, coat and stay wet over time but reeks to high hell and will stink up everything it contacts- you included. If you're feeling adventurous, you can mix up your own solution (WD-40 did). Or just spend a few bucks on a large can of Marvel Mystery oil, WD-40, or PB Blaster. Know what metal that you are working with and apply the correct solution to get the best result. Most metals will form what is known as an oxide, where oxygen from the air mixes on the surface with the base metal. We do know that when these oxides dry out they are usually hard to remove by any means other than mechanical (sanding or wire brush/wheel, sand/bead blasting). We know that steel or iron will rust. Aluminum will form a white powdery residue (aluminum oxide, or aluminum 'rust) and may form a dark grey to almost black coating caused by the oxidation of the metal. Brass and copper will be covered with a green corrosion. Each condition will require a different approach in most cases. Heat is an excellent tool for unsticking things, but only when used in moderation. Would hitting a stuck piston help it to move? The answer is, yes and no. If you apply enough force in the proper direction, yes it would help. If you just wound up and smacked it dead center with a ball peen hammer, you would probably just put a hole in it and it would still remain stuck. The better way to approach this when you have a stuck engine would be this way: *Determine what is stuck. Is it the piston(s), the crank, the cam and valve train, the rods, or a combination of all these? *Break the engine down until you find that part or combination of parts. *It would be a hell of a waste if we just gave up on an engine just because it wouldn't turn over. How about turning it back? Could we have just dropped a valve on the piston and it's stuck there? *Remove non-essential accessories that aren't required to make the engine rotate. That means that you can loosen the belts or remove the alternator, water pump, intake and exhaust manifolds, distributor, heads, oil pan, etc. Get it down to where you can have a good look around and see where the problem area lies. *Keep the engine in a secure holding device. If it's the frame of the car or truck, that's good. If the engine is loose, find a way to hold it down. Remember, the tensile strength of steel is greater than wood. And if one bolt is good, a half a dozen would be better. If using an engine stand, use caution that it doesn't tip. A light-duty three wheeled engine stand won't do it if a long breaker bar is going to be used to turn the crank. *Flood the engine block with the fluid of your choice. Turn it upside down and fill the block, and plug holes as necessary. This is just a pre-lube stage. *Using an oak block and a dead blow hammer of your choice, SHOCK each piston with a few blows. An air chisel with a flat bit and an oak block like the mushroom end of an axe handle works well. Remember you are just trying to loosen the rings, NOT move the piston. Just let the bit vibrate the oak block and piston. When the rings break free you will see your lube run past them into the block. Any piston which is at TDC or BDC will not give you any mechanical advantage in rotating the assembly by hitting it. The initial strike is to just loosen the rings in the piston lands and break the rings free from the walls of the cylinder. Pistons that are in between TDC and BDC will provide the best opportunity to move within the bore. *There are two places in which you can apply rotational force; the crank pulley and the flywheel. Use whichever is accessible with the least effort. Do not use pulleys or the outside ring of balancers to turn over the engine if at all possible. Don't use the balancer bolt, either. Damper/balancers can be damaged and the damper bolt will strip if excessive torque is applied. Instead, the safest/easiest way to turn the crank is to use a tool that allows a large ratchet or breaker bar to be used, like the crank turning devices shown below. Both sockets that use the crank key, and adapters that bolt to the inner hub of the damper are made for turning the crank. Crank keys and keyways can shear with abnormal force. Be sure of the bolt grades before applying force. Remember to try to rock the crank CW and CCW. {| |[[File:Crank turning tool.jpg|thumb|400px|Damper-mounted crank turning tool]] |[[File:Crank turning tool2.jpg|thumb|400px|Crank snout-mounted crank turning tool]] |[[File:Flywhl tool.jpg|thumb|400px|Flywheel turning tool]] |} <br style="clear: both"/> *Don't forget to use longitudinal force on the crankshaft. Tap the crankshaft at both ends with your dead blow hammer and oak block, like you were going to measure the crank end float. Loosen the rod bearing caps and tap with a bronze hammer to break the bearings loose. *After you've done all of the above, let it soak and then start over again. ===Miscellaneous=== After trying the aforementioned soaking to no avail, determine which cylinder is on the compression stroke by removing the spark plugs and using a compression gauge hose or other hose that fits snugly in the spark plug hole. Blow in the hose, if you can't easily then you have the one on compression stroke (if you use a compression tester hose make sure it has no Schrader valve in it). Break the porcelain out of an old spark plug and thread the metal body for a large grease fitting (1/4" NPT). Insert the plug in the cylinder that's on the compression stroke and pump it full of grease using a grease gun filled with cheap light weight grease (like Lubriplate white grease). Once the motor breaks free you can rotate the motor to squeeze most of the grease out of the spark plug hole. Another approach is to put some Marvel Mystery Oil, WD-40 or PB Blaster into each cylinder and then pressurize with compressed air. On cylinders that are not under compression, the compressed air will distribute the penetrating oil. With the cylinder under compression, the compressed air will act to rotate the engine while driving the penetrating oil past the rings. There are tales of Coke being used to loosen a stuck engine. Presumably this has something to do with the small acid content of Coke. Try it if you want to. {{Warning}}Use good eye protection. Blow compressed air into all the cylinders to coat the cylinders and piston tops with the penetrant. Give it a couple minutes/hours/days so it can work on the rust. Afterwards, screw in the compressed air adapter and charge each cylinder with fifty or so psi. It helps if you completely loosen the rockers first so any cylinder you charge has the valves closed. If it doesn't turn over at fifty psi it's not ready. Apply more oil and wait. It's time consuming and may be a bit of work, but the object is to SAVE the engine.
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