Isuzu L Series User Manual

II. Engine Component Description
U L-Series Diesel 19
Cooling System
Below is the coolant flow diagram. Good coolant circulation is ensured by utilizing water
jackets formed with a one-piece casting core, which eliminates burrs in the water passage.
Maintain a coolant/water solution concentration ratio of
50
/
50
. Use only de-mineralized (soft)
water, since hard water tends to neutralize the corrosion inhibitors in the antifreeze and add
scale (particularly in hot spots) to the cooling system. It is absolutely
required
that you use a
low-silicate formula anti-freeze. Do not add any additional water pump lubricants to the
cooling system. Refer to the Workshop Manual for radiator cap and cooling system testing
and specifications.
Use a commercially available antifreeze tester when testing for coolant/water mixture. Testing
for pH is essential, as too high an acidity or alkalinity can cause severe damage to the engine
and cooling systems. The pH readings should be 7.5-8.5 (SAE J1034 allows for 7.5-11.0).
Litmus test paper is available from most commercial tool suppliers and product distributors.

Isuzu L Series Specifications

General

Brand	Isuzu
Model	L Series
Category	Engine
Language	English