Bulletproof cooling system
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*Before installing the water pump, grasp the impeller with one hand and the drive hub with the other and twist to make sure the impeller is tight on the drive shaft. Not finding this problem beforehand can make you crazy. | *Before installing the water pump, grasp the impeller with one hand and the drive hub with the other and twist to make sure the impeller is tight on the drive shaft. Not finding this problem beforehand can make you crazy. | ||
*Although it may not be necessary, the concept of a "water pump conversion disc" is intriguing. Flow Kooler originally marketed flat aluminum discs to rivet to the backside of the stamped steel impeller in the pump. With an iron impeller, a steel disc could be welded or brazed onto the impeller. The disc wouldn't be that difficult to fab up yourself. Space the water pump backing plate back farther with a couple of gaskets to prevent interference of the rivet heads on the backing plate if riveting a disc to a stamped steel impeller. More info: [http://www.smokstak.com/forum/showthread.php?t=11774 brazing cast iron], [http://store.summitracing.com/partdetail.asp?part=BRA%2D4375%2D07&autoview=sku Flow Kooler water pump conversion discs]. This disc should make an appreciable difference in the flow of water at engine speeds under 3,000 RPMs. On the other hand, Howard Stewart of Stewart Components (the guy with the water pump dyno), says that the disc's have little to no effect. | *Although it may not be necessary, the concept of a "water pump conversion disc" is intriguing. Flow Kooler originally marketed flat aluminum discs to rivet to the backside of the stamped steel impeller in the pump. With an iron impeller, a steel disc could be welded or brazed onto the impeller. The disc wouldn't be that difficult to fab up yourself. Space the water pump backing plate back farther with a couple of gaskets to prevent interference of the rivet heads on the backing plate if riveting a disc to a stamped steel impeller. More info: [http://www.smokstak.com/forum/showthread.php?t=11774 brazing cast iron], [http://store.summitracing.com/partdetail.asp?part=BRA%2D4375%2D07&autoview=sku Flow Kooler water pump conversion discs]. This disc should make an appreciable difference in the flow of water at engine speeds under 3,000 RPMs. On the other hand, Howard Stewart of Stewart Components (the guy with the water pump dyno), says that the disc's have little to no effect. | ||
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| + | NOTE: Viscous fan couplings can be a fruitful source of overheating. Sometimes these will appear to be stiff when cold but they will free-wheel when hot! As the units have such a brief lifespan the writer likes to scrap these units and fit a solid fan (a differently pitched fan will be needed) For the best cooling an electric fan ''blowing'' into the radiator is a good arrangement. | ||
==Swapping a core support and matching radiator into a recipient vehicle== | ==Swapping a core support and matching radiator into a recipient vehicle== | ||
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The "usual" drive ratio of a SBC mechanical water pump is between 1:1 and 1.3:1, over driven. | The "usual" drive ratio of a SBC mechanical water pump is between 1:1 and 1.3:1, over driven. | ||
| − | + | In the writers opinion the LOCATION of the pump is of great importance. Some vehicles have been built with high mounted water pumps which have been a disaster. In the case of a vehicle which has its engine mounted north-south, the water pump will often become the highest component in the cooling circuit when the vehicle is ascending a steep hill. Engine designers ought to study Steam Trapping and Air Venting as it is a very important topic even for things that do not run on steam. | |
With a transverse engined vehicle it is possible to have the water pump behind the engine block. With this arrangement steep hills will not starve the pump of water. AVOID any car that relies on venting screws in its cooling system. | With a transverse engined vehicle it is possible to have the water pump behind the engine block. With this arrangement steep hills will not starve the pump of water. AVOID any car that relies on venting screws in its cooling system. | ||
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The purpose of the radiator is to get the engine up to operating temperature as quick as possible, help it maintain optimum temperature, and remove excess heat when required. "Radiator" is essentially just another name for a heat exchanger, whereby combustion temperatures up to 4500 degrees are transferred to the cooling system of the engine block and taken outside the block via flexible rad hoses to be exposed to the cooling force of air through the rad core, thus reducing the temperature of the coolant before returning it to the engine block. There are two restrictions in the system. One is the thermostat, which restricts flow and holds heat in the engine until warmed up, and the other is the rad core tubes. The rad tubes have to be of sufficient size so as to allow the coolant to flow through in an unrestricted manner, but also able to 'scrub off' BTU's or heat; which is based on the shape of the tube and the convection of heat away from the coolant to the outside air. A wide flat tube will expose more surface to the outside flow of air than a narrow tube . The reason for this is more surface area is exposed to cooling. Look at the pictures located below and see why that is. | The purpose of the radiator is to get the engine up to operating temperature as quick as possible, help it maintain optimum temperature, and remove excess heat when required. "Radiator" is essentially just another name for a heat exchanger, whereby combustion temperatures up to 4500 degrees are transferred to the cooling system of the engine block and taken outside the block via flexible rad hoses to be exposed to the cooling force of air through the rad core, thus reducing the temperature of the coolant before returning it to the engine block. There are two restrictions in the system. One is the thermostat, which restricts flow and holds heat in the engine until warmed up, and the other is the rad core tubes. The rad tubes have to be of sufficient size so as to allow the coolant to flow through in an unrestricted manner, but also able to 'scrub off' BTU's or heat; which is based on the shape of the tube and the convection of heat away from the coolant to the outside air. A wide flat tube will expose more surface to the outside flow of air than a narrow tube . The reason for this is more surface area is exposed to cooling. Look at the pictures located below and see why that is. | ||
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| + | In England the problem with copper radiators is corrosion of the fins. Eventually just the tubes will be left. This unfortunate state of affairs is virtually guaranteed to be reached in considerably less than ten years if one lives near the ocean. | ||
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| + | [[Image:Tube_sizes.gif|frame|Tube sizes.]] [[Image:Alum_vs_copper_brass.gif|frame. Aluminum vs. copper/brass]] | ||
==Aluminum radiators== | ==Aluminum radiators== | ||
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NOTE: Thermostat information; Courtesy of Chris Hoffman choffman@stantinc.com , via email. For further information contact Chris Hoffman, 1620 Columbia Avenue Connersville, Indiana 47331-169 1-800-822-3121 | NOTE: Thermostat information; Courtesy of Chris Hoffman choffman@stantinc.com , via email. For further information contact Chris Hoffman, 1620 Columbia Avenue Connersville, Indiana 47331-169 1-800-822-3121 | ||
| + | NOTE: The old type of thermostat used metal bellows filled with a liquid. The condensed liquid would "suck" the bellows closed. This type of thermostat always fails in the open position which is extremely convenient as one does not have to buy a new cylinder head or engine. Nowadays this type is very difficult to obtain. | ||
==Miscellaneous== | ==Miscellaneous== | ||
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| − | '''OIL COOLERS:''' Some cars will have the oil cooler installed in the radiator. In the writers opinion this is an extremely bad idea as (1) Regarding cooling, one has all ones eggs in one basket. (2) There is the risk of oil getting into the water or vice-versa. Note that an oil-to-air heat exchanger is extremely difficult to boil and it is a reliable method of getting rid of waste heat. | + | '''OIL COOLERS:''' |
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| + | Some cars will have the oil cooler installed in the radiator. In the writers opinion this is an extremely bad idea as (1) Regarding cooling, one has all ones eggs in one basket. (2) There is the risk of oil getting into the water or vice-versa. Note that an oil-to-air heat exchanger is extremely difficult to boil and it is a reliable method of getting rid of waste heat. | ||
Regarding combined coolers, allegedly a £57,000 German car uses a transmission cooler in the radiator for its fancy six speed gearbox. For some reason (allegedly the transmission fluid attacking the pipe) leaks occur. When this happens the pressurised engine coolant fills the gearbox which then explodes! The owner of the car has had this happen twice in two years and he describes the car as "Fifty seven thousand pounds-worth of c#@p" (however he needs it for his business). My own British made car has six heat exchangers and NONE of them are combined. This gives better reliability even though it is old and only cost about one percent of the price of the German limo. | Regarding combined coolers, allegedly a £57,000 German car uses a transmission cooler in the radiator for its fancy six speed gearbox. For some reason (allegedly the transmission fluid attacking the pipe) leaks occur. When this happens the pressurised engine coolant fills the gearbox which then explodes! The owner of the car has had this happen twice in two years and he describes the car as "Fifty seven thousand pounds-worth of c#@p" (however he needs it for his business). My own British made car has six heat exchangers and NONE of them are combined. This gives better reliability even though it is old and only cost about one percent of the price of the German limo. | ||
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