Hi all, Back again with some interrogations. I am continuing on this topic: ,I would like to mention the fact that there is no indication on how to interpret a peak of Sodium (Na) in an engine oil analysis. I am trying to build a simple flowchart to interpret sodium contamination. Considers a CAT Generator set, a simple CAT generator set. What are the actions to take when you notice that the ppm of Na is at a critical level? I have been told that : 1st, when you noticed a high value of sodium, you have to check the PH of the coolant to see if it’s in the acceptable range. If not, it means that the ELC has corrosive properties 2nd, you can then check the water pump (rings), after cooler, the cylinder head gasket, etc. to look for leaks. Is that correct??
If you are using "conventional" glycol-based coolant that uses SCA (Supplemental Coolant Additives) look for Sodium, if you are using organic-acid based ELC look for potassium. Any sharp increase in the value of Na/K (depending on your type of coolant) indicates coolant in the engine oil. Do you keep records of how much oil and coolant is added in between the fluid changes that you do during regular Preventive Maintenance..? If not you should do this. Is coolant being added on a regular basis to the radiator..? A "yes" answer would indicate you are losing coolant. (We find that this is one of our best indicators of a pending cylinder head gasket failure on Cat 3500-series engines.) Coolant will screw up the lead-tin overlay (LTO) on crankshaft bearings really rapidly. Look for a spike in lead in the oil analysis (normally it will be 0 or 1 and maybe spike to the 3-4 range before returning to 0-1) at the same time or maybe one sample after you first see the spike in Na/K. The presence of Na/K means you have coolant in the oil. Stop the engine immediately and discover the source. Repair as necessary. It could be cylinder head gasket, cylinder liner seals, water pump or engine oil cooler. An oil cooler failure however will often result in oil in the coolant as well as coolant in the oil. So if you don't have visible oil in the radiator an oil cooler failure is less likely, but not impossible.
Thank you Nige. So to sum up: 1st : Between two PM (Before any oil analysis ), always check the record of coolant added If coolant is added on regular basis ==> It means there is a leak. ==>Look for the leak. 2nd : Perform oil analysis at the PM and look the value of Na/K (depending on the type of Coolant) 3rd : Any peak of Na/K confirm the leak. ==>3rd bis, check the value of lead (look for a spike) to confirm (be sure) that there is coolant screwing up the lead overlay. 4th : Question: Do all the specifications above can be applied this for a CAT 3406 engine ? And no other PH analysis interpretation is required?
Your summary is correct, and that analysis would also apply to a 3406.