101602-1561 ZEXEL 9 400 611 508 BOSCH INJECTION-PUMP ASSEMBLY 9400611508 1016021561

The preferred method for obtaining a representative coolant sample is to draw a sample from a coolant sampling valve that is located at a point where coolant is flowing freely. Do not take samples from any cooling system drain valves.If no suitable coolant sampling valve is available and the use of a vacuum sampling pump is required, do not use the same vacuum sampling pump for extracting oil samples that is used for extracting coolant samples. Do not draw a sample from the coolant overflow tank as it will not be representative of the coolant in the system.A small residue of either type sample may remain in the pump and may cause a false positive analysis for the sample being taken.Always use a separate pump for oil sampling and a separate pump for coolant sampling.Failure to do so may cause a false analysis which could lead to customer and dealer concerns.
New Systems, Refilled Systems, and Converted Systems
Perform an S O S coolant analysis (Level 2) at the following maintenance intervals.
Every Year
Initial 500 service hoursPerform this analysis at the interval that occurs first for new systems, for refilled systems, or for converted systems that use Cat ELC (Extended Life Coolant) or use Cat DEAC (Diesel Engine Antifreeze/Coolant). This 500 hour check will also check for any residual cleaner that may have contaminated the system.Recommended Interval for S O S Services Coolant Sample
Table 1
Recommended Interval    
Type of Coolant     Level 1     Level 2    
Cat DEAC     Every 24140 kilometers (15000 miles) (1) (2)     Yearly (2) (3)    
Cat ELC     Optional (3)     Yearly (3)    
( 1 ) This is also the recommended sampling interval for all commercial coolants that meet Cat EC-1 (Engine Coolant specification - 1)
( 2 ) The recommended sampling interval for all other conventional heavy-duty coolant/antifreeze is 20120 kilometers (12500 miles).
( 3 ) The Level 2 Coolant Analysis should be performed sooner if a problem is suspected or identified.Note: Check the SCA (Supplemental Coolant Additive) of the conventional coolant at every oil change or at every 250 hours. Perform this check at the interval that occurs first.S O S Services Coolant Analysis (Level 1)
A coolant analysis (Level 1) is a test of the properties of the coolant.The following properties of the coolant are tested:
Glycol concentration for freeze protection and boil protection
Nitrite concentration
pH
Conductivity
Visual analysis of color, appearance, foaming tendency, and observation of any visible contaminants such as precipitates, oil, or fuel
Odor analysisThe results are reported, and appropriate recommendations are made.S O S Services Coolant Analysis (Level 2)
A coolant analysis (Level 2) is a comprehensive chemical evaluation of the coolant. This analysis is also a check of the overall condition of the cooling system.The S O S coolant analysis (Level 2) has the following features:
Full coolant analysis (Level 1)
Measurement of concentrations of all coolant corrosion and cavitation inhibitors
Identification of metal corrosion and of contaminants
Identification of buildup of the impurities that cause corrosion
Identification of buildup of the impurities that cause scaling
Determination of the