COOLING SYSTEM DESCRIPTION The  purpose  of  the  cooling  system  is  to  maintain  the  most efficient  operating  temperature  of  an  engine  without  causing damage to the components.  Approximately 1/3 of the energy produced   when   fuel   burns   is   converted   into   power   by   the engine.    The  other  2/3  of  the  energy  must  be  disposed  of  by the exhaust system and the cooling system or engine damage will result. Basically, the circulation of coolant through the cooling system relies  upon  the  water  pump.    The  water  pump  draws  coolant from  the  radiator  and  forces  it  through  the  water  jackets  and cylinder heads, where it  accumulates  heat.    The  coolant  then flows to the upper radiator tank and down through the radiator where it is cooled by air ’drawn through the radiator fins. The damages or effects caused by cooling system neglect are usually   gradual   and   are   therefore   often   overlooked.      This manual provides the reader with basic component knowledge, maintenance   procedures,   service   intervals,   trouble-shooting and coolant and inhibitor recommendations. COOLANT The  selection  and  maintenance  of  the  engine  coolant  is  as important to long engine life as the selection and changing of the engine lubricating oil and oil filters.  The following  section provides    IH’s    recommendations    for    selecting    the    engine coolant and maintenance of the coolant inhibitors. COOLANT SELECTION IH  engines  will  operate  successfully  with   a   water/antifreeze mixture  or  inhibited  water  as  the  coolant.    Never  use  water alone  as  it  allows  rust,  scale  deposits  and  corrosion  to  occur within the engine. Water Water  used  in  the  cooling  system  must  meet  the  following standards: 1. Total  Hardness  not  to  exceed  170  parts  per  million (10 grains/gallon maximum) to prevent scale deposits.      Water   containing   dissolved   magnesium and  calcium  (the  usual  reason  for  water  hardness) above the specified amount will cause scale deposits to develop in the engine. 2. Chlorides   not   to   exceed   40   parts   per   million   (2.5 grains/gallon maximum) to prevent corrosion. 3. Sulfates   not   to   exceed   100   parts   per   million   (5.8 grains/gallon maximum) to prevent corrosion. 4. Dissolved  Solids  not  to  exceed  340  parts  per  million (20    grains/gallon    maximum)    to    minimize    sludge deposits,  scale  deposits,  corrosion  or  a  combination of these. If any of the above requirements cannot be met, use distilled, de-ionized  or  de-mineralized  water.    Water  samples  can  be tested  by  water  treatment   laboratories   to   determine   if   local water supplies meet these standards.  "Softened" water that is prepared    using    common    salt    (sodium    chloride)    contains excessive  amounts  of  chlorides  which  will  interfere  with  the water    softening    capabilities    of    coolant    filters    using    ion- exchange resins. Anti-Freeze IH  Anti-Freeze  and  Coolant  contains  all  necessary  inhibitors and has been tested for use in IH products.  It is an ethylene glycol type anti-freeze and compatible with chromate and non- chromate type coolant filters. Several factors should be considered for successful operation when using ethylene glycol type anti-freezes. 1. The    boiling    point    of    ethylene    glycol    anti-freeze solutions is higher than plain water but their ability to transfer   heat   is   less.      Therefore   in   hot   weather, coolant   temperatures   will   run   higher   than   systems containing   plain   water.      This   also   holds   true   for engine lubricating oil and transmission oil temperatures where oil to water coolers are used. 2. An   anti-freeze   concentration   greater   than   68%   will adversely  affect  freeze  protection  and  heat  transfer rates.      Anti-freeze   concentrations   between   68   and 100%  actually  have  a  higher  freezing  point  than  a 68%   anti-freeze   concentration.      Due   to   the   higher freezing    point    and    reduced    heat    transfer    rates, concentrations greater than 68% should not be used. It is also important to remember that anti-freeze may retain its freeze protection for more than one season but  coolant  conditioners  must  be  added  to  maintain corrosion protection.  Figure 1 illustrates the freezing point   of   anti-freeze   according   to   its   percentage   of concentration. 3. Anti-freeze   containing   sealer   or   anti-leak   additives should  not  be  used  in  IH  engines.    These  additives may  cause  plugging  problems  in  the  cooling  system and restrict coolant flow. 4. Anti-freeze    formulated    with    methoxy    propanol    or propolene  glycol  is  not  recommended  for  use  in  IH engines, due to a reaction with engine internal seals, coolant  hoses  and  potential  fire  hazard  due  to  lower flash points than ethylene glycol type antifreeze. 5. The   use   of   methanol   alcohol   or   methoxy   propanol (Dowtherm    209)    based    anti-freeze    may    result    in separation of the anti-freeze and water. Coolant Conditioners All cooling system inhibitors, including those in antifreeze solutions, become depleted through normal operation.      If   the   inhibitors   in   anti-freeze   are   allowed   to become depleted, the anti-freeze becomes corrosive CTS-4181 Page 3