Cooling system Checking coolant level Checking antifreeze and cor- rosion inhibitor The following instructions apply to Scania ex- pansion tanks. For other types of expansion tanks, follow the manufacturer's instructions. Designation Illustration Refractometer WARNING! Never open the coolant filler cap when the en- gine is hot. Hot coolant and steam may spray out and cause burns. If the cap has to be opened do it slowly and care- fully to release the pressure before removing the cap. Wear gloves as the coolant is still very hot. 305 523 Note: Use only pure fresh water that is free from parti- cles, sludge and other impurities. 138008 1.
Open the expansion tank cap and check the coolant level. The right coolant level on a cold engine is even with the lower edge of the filler neck. The right coolant level on a hot engine is approximately 25 mm (1 in) over the low- er edge of the filler neck. 1. Pour a small amount of coolant into a con- tainer and check that the coolant is pure and clear. 2. Change the coolant if it is contaminated or cloudy. 2. Top up with coolant as necessary. IMPORTANT! 3. Measure the antifreeze and corrosion inhibi- tor content with a refractometer. Do not top up large quantities of coolant through the expansion tank.
Top up in accordance with the instructions in the section headed Changing coolant instead. The following rules apply to ethylene glycol- based coolant: The antifreeze and corrosion inhibitor content must be minimum 35 percent by volume for corrosion protection to be sufficient. An antifreeze and corrosion inhibitor content greater than 55 percent by volume impairs the ability to protect against frost. If ice forms in the coolant, there are disrup- tions initially, but there is no immediate risk of damage. The engine should not be subject- ed to heavy loads when ice starts to form. IMPORTANT! Never fill a large amount of cold coolant in a hot engine.
There is great risk of cracks forming in the cylinder block and cylinder heads. IMPORTANT! Only pour pre-mixed coolant into the cooling system. OPM 300 en-GB 49 © Scania CV AB 2015, Sweden