Freeing a stuck engine

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(Breaking the engine loose)
(Unsticking the "impossible")
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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.
 
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 iy'll 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.
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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 penetrating fluids===
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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).
 
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 use a different approach in most cases.
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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:
 
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:
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*Break the engine down until you find that part or combination of parts.
 
*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?  
 
*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 off 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.
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*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. Alight-duty three wheeled engine stand won't do it a long breaker bar is going to be used to turn the crank.
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*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.
 
*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. A air chisel with a flat bit and an oak block like the mushroom end of an axe handle works good, 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.  
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*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. One is the crank pulley and the other is the flywheel. Use whichever is accessible the easiest. 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.  
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*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.  
 
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|[[File:Crank turning tool.jpg|thumb|400px|Damper-mounted crank turning tool]]
 
|[[File:Crank turning tool.jpg|thumb|400px|Damper-mounted crank turning tool]]

Revision as of 08:49, 30 May 2015

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