GILLIG LOW FLOOR, Руководство по обслуживанию

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Engine
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Supplemental Coolant Additive (SCA)
Testing the additive concentration level at scheduled intervals is essential (See the Preventive Main -
tenance chapter). Coolant additives provide the cooling system with corrosion protection, cavitation
suppression, pH control, and scale prevention. Be sure to follow the additive manufacture’s instructions.
Coolant additives must meet ASTM SCA standards (for more information, go to www.astm.org).
Call your Cummins Service representative for a list of approved brands of SCA.
Always maintain the proper concentration of coolant and coolant
additive. Failure to do so can result in engine damage.
Do not use sealer additives in the cooling system. Stop-leak additives
could cause plugging in the cooling passages.
1. Premix the water/antifreeze solution (and supplemental additive, if required after testing) in a
container. Premix the coolant solution in a container of sufficient size in the following order:
a. Soft, clean water
b. Antifreeze (ethylene glycol or propylene glycol)
c. Supplemental coolant additive.
Do not pour contents in the surge tank separately. They must be
thoroughly premixed in the above order.
Wait until the engine has cooled before pressing the relief valve to avoid
being sprayed with hot coolant.
2. Press the pressure relief valve (vent cock) on the surge tank, and hold it in the depressed position
until all the pressure is relieved from the system.
3. Open the surge tank filler cap. Slowly fill the system with the coolant solution until the sight
glass on surge tank indicates the system is full.
4. If the coolant level was very low, loosen the bleed screw on the upper coolant pipe to make sure
all air is expelled from the system.
5. Test for coolant additive concentration. Refer to the engine manufacturer’s manuals for pro-
cedures on testing additive concentration. Add additive to the system if low. Be careful not to
overconcentrate the coolant with additive.