MCi Crusader II 1989 Maintenance Manual page 202

Date
1-1-89
Page ____
6 -_ 3 _ _
MC-9 MAINTENANCE MANUAL
NOTE: Specific instructions are set forth
below concerning coolant requirements,
antifreeze, use of water in the system, cor-
rosion inhibitors, silicate gel formation and
coolant testing.
COOLANT REQUIREMENTS
Coolant solutions must meet the following basic require-
ments:
1 Provide for adequate heat transfer.
2. Provide a corrosion-resistant environment
within
the
cooling system. .
3. Prevent formation of scale or sludge deposits in the cool-
1ng system. Figure 6-3 contains water quality data.
4. Be compatible with cooling system ·hose and seal
matenaJs.
5 Provide adequate freeze protection during cold weather
ooerat1on and boil-over protection in hot weather.
The first four requirements are satisfied by combining a
suitable water with reliable inhibitors. When freeze protection 1s
required. a solution of suitable water and an antifreeze con-
taining adequate inhibitors will provide a satisfactory coolant.
Ethylene glycol-based antifreeze solutions are recommended
for year-round use.
WATER
Whether
cf
drinking quality or not. any water will produce a
corrosive environment ,n the cooling system. and the mineral
content may permit scale deposits to form on internal cooling
svstem surfaces. Therefore. water seler,ted as a coolent must
be properly treated with 1nl11bitors to control corrosion and
sca1e deoosit1on.
To determine ,ta particular water is suitable for use as a
coolant when properly inh1b1ted. the following characteristics
must be considered: the concentration of chlorides and sul-
fates. total hardness. and total dissolved solids.
Chlorides and/or sulfates tend to accelerate corrosion.
wn11e·hardness (percentage of magnesium and calcium salts
broadly classified as carbonates) cause deposits of scale. Total
dissolved solids may cause scale deposits. sludge deposits.
corrosion. or a comb1nat1on of any of these. Chlorides. sulfates.
rnagnes1um and calcium are among the materials which make
up dissolved solids. Water within the limits specified in Table 1
111gure 6-3) is satisfactory as an engine coolant when proper
,nhibitors are added. The procedure for evaluating water
intended for use
in
a coolant solution 1s shown in Table 2.
TABLE 1
PARTS PER GRAIN$ PER
MILLION GALLON•
Chloride (Ma,nmum) 40 2.5
Sulfates (Maximum) 100 5.8
Total OtSSOived Solids (Maxunuml 340 20
Tota, Hardness (Ma•imumJ 170 10
R&ter to
Tab,e
~
tor
tW&Juanon of water 1n1ended for use in a coolacit solutH>n.
'4.5 liters
TABLE2
Determine The
Conceflntions
01 Chlo,-t<les, Sulfates. And
Total OissOlv<!d Sohds
ChlondeS Un- 40
l)llm.
.-\nd
Sulfates Un- 100
pgm.
And
Total Oi""°!Ved Sokds
Un-3.&0ppm.
Oetemune Total
Hardn .... Of The _..,
In The W.111<
Total Hardness
un-•701)!)ffl
Total Hardness
0-170ppm
Soften
TheWlla<
Clilondfl
Under <60 pgm •
Or
Sulla"'" UndM 100
PJ)f11.
Or
Total Oissoi"9<1 Solids
o-3-40ppm.
Di,:till.
0e .. nuneratize
Or 0.-ionlZe TIMI Wll8t.
Wa18t
Su11abfe !0<
Use
As
COOiant
Plue ltlhtbllors
Figure 6•3. Cooling Fluid Characteristics.
ANTIFREEZE
When freeze protection 1s required. use an antifreeze that
meets the GM 6038M formulation. which limits silicate to 0. 1 5%
maximum. or an equivalent formulation meeting the 0.15% maxi-
mum sihcate and GM 1899M performance requirements.
Solutions of less than 30% do not provide adequate cor-
re>s1on protection. Concentrations over 67% adversely affect
freeze protection. heat transfer rates. and silicate stability. A
50% ani1freeze solution 1s normally used as factory-fill.
Ethylene glycol base antifreeze is recommended. Methyl
alcohol base antifreeze 1s not recommended because of its
effect on the non-metallic components of the cooling system
and because of its low boiling point Methoxy propanol base
antifreeze 1s not recommended due to the presence of fluoro-
elastomer seals ,n the cooling system.
The inhibitors in antifreeze sol u,ions should be replenished
w1tn a non-chromate corrosion 1nh1bitor supplement when
indicated by testing the coolant. Engine coolant should be
checked at approximately 500 hour or 20.000 mile intervals
iSee Coolant Testing. below.)
Antifreeze solutions should be used year-round to provide
freeze protection 1n the winter. boil-over protection
in
the
summer. and a stable environment for seals and hoses 1n the
cooling system of the engine. (See figure 6-4.)