GAGE- 2506866 - Caterpillar

Engine All Gas EnginesIntroduction
Do not perform any procedure in this Special Instruction until you have read the information and you understand the information. The procedure below identifies how to troubleshoot gas engine nitrate levels.Troubleshooting Procedure
Table 1
Troubleshooting Test Steps Value Results
1. Take a Nitrite Level Sample of the Coolant Using the 4C-9301 Coolant Conditioner Test Kit
A. Take a pH level sample of the coolant.
B. Observe any odors around the engine.
Nitrite levels
Result: The nitrite level is depleted or near zero and the pH is less than 8.5. This condition can be caused by severe aeration and overheating.
Repair: Check for air leaks in the system or conditions that may cause overheating. Repair any conditions found that cause air leaks.
Result: The nitrite level is depleted to near zero and the pH is above 8.5. This condition can be caused by a possible electrical fault.
Repair: Check the system for a stray current or a loose ground wire. Repair any wires as necessary.
If the problem is not resolved, proceed to Test Step 2.
2. Check the pH Level of the Coolant.
pH level
Result: The pH level is below 6.0. This condition can be caused by cross contamination of the exhaust gas into the coolant system.
Repair: Check the water-cooled exhaust manifold and coolant system for leaks. Repair any gas entries found in the cooling system.
If the problem is not resolved, proceed to Test Step 3.
3. Check for Nitrites Levels, Ammonia Odor, and Color Change of the Coolant.
Coolant condition
Result: Nitrites are near zero, there is an ammonia odor, and/or the color has changed from orange to yellow then clear. This condition can be caused by nitrites reacting with aluminum. The silicate barrier has been depleted.
Repair: Dose with the SCA to replenish the silicate level. Check the silicate level with a Level ll SOS Analysis.
If the problem is not resolved, proceed to Test Step 4.
4. Check the Coolant for a Burnt Odor With or Without an Associated Solvent Odor.
Coolant odor
Result: There is a burnt odor with or without an associated solvent odor. This condition can be caused by localized overheating and during no flow conditions.
Repair: Check for localized overheating with low flow or severe general overheating. Repair any conditions found that cause the overheating.
If the problem is not resolved, proceed to Test Step 5.
5. Check the Coolant for a Solvent Odor.
Coolant odor
Result: There is a solvent odor with no other odors associated. There are localized overheating conditions.
Repair: Check for an oversized block heater on an idle piece of equipment or a malfunctioning thermostat controlled heater on a stand-by generator.