0328622 JOHNSON GASKET, Manifold to crankcase

Introduction
Table 1
Revision History
Revision Summary of Changes
05 Added effectivity
04 Added prefixes K2D, HFB, D5T, LW5, PN5, RE5, TP5, WE5
03 The psi was updated from 375 to 400 in step 1 of the solution. The Caterpillar SOS lab will only check for percent fuel content if the oil viscosity is below a certain threshold. If oil viscosity is above their determine threshold the presence of fuel does not need to be checked. The Caterpillar SOS lab worldwide database has only 3% of S/N:SSL, ; S/N:MTL, ; S/N:CTL, and ; S/N:CWL models with fuel dilution flagged, so this is not a frequent problem. Fuel dilution can occur when there is an engine failure, lack of maintenance with DPF, not using low ash oil, not using Ultra Low Sulfur Diesel, or even when the machine is being operated in a low load application.Before getting into the troubleshooting steps, there needs to be an understanding of regeneration. The C3.3B Tier 4 Final (Stage IIIB) and C3.8 Tier 4 Interim (Stage IIIB) and Final (Stage IV) use passive and active regeneration. This needs to be understood for how they impact fuel dilution.Passive regeneration occurs naturally when aftertreatment temp is above 350° C (662° F). Active regeneration is in-cylinder dosing, which is the most common active regeneration method for these engine displacements. In-cylinder dosing is used to increase the temperature of the DPF. This is achieved by the 4 fuel injectors injecting fuel during the exhaust stroke. When the fuel reaches the DOC, it chemically reacts to produce heat into DPF for regeneration (removal of soot). During the in-cylinder dosing some fuel will mix with oil on cylinder walls.The DPF has a 3,000 hour maintenance interval for cleaning. As the DPF gets full of soot and ash, the active regenerations occur more frequently. The more frequent the in-cylinder dosing the more likely fuel dilution can occur. When the DPF is full and requires cleaning, a 523602-0 Active Regeneration code will occur. This code indicates that active regenerations occurred 3 times within 30 minutes (Refer to Troubleshooting, UENR3423, DPF Active Regeneration Occurrences is Excessive for further details). When this code occurs fuel dilution will be present.Problem
Fuel dilution reported in oil samples on certain machines. Oil sample interpreters frequently mention fuel injectors as the possible cause. However there are other more common reasons that would cause fuel dilution. Itis recommended to followthis troubleshooting procedure when one of these engines are flagged for fuel dilution.Solution
If there is an engine with fuel dilution, check what service letters that apply to that machine. If the dipstick tube was replaced, then start with the Step 1 of the troubleshooting steps. If your machine is a Compact Wheel Loader or did not have the dipstick tube replaced, then skip to Step 2.
If the replacement of the dipstick tube was performed when the engine has 750 hours or more, dirt may have entered the engine via the bore for the dipstick tube. If dirt has entered the engine, the cylinder bores may be worn causing oil consumption. Oil consumption will cause the DPF to plug prematurely and cause frequent active regeneration that can result in fuel dilution.
Recommended actions: Prior to changing the oil, obtain an oil sample. Review the oil sample history. If wear metals or Silicons (Si) are currently high or were high on previous samples, then recommend performing a compression test (refer to Testing and Adjusting). For the C3.3B a new engine compression is 460 psi and allowable is 320 psi. Based on DSN tickets for dipstick tube issue, would recommend removing the cylinder head and visually checking and measuring cylinder bore if compression is 400 psi or less.
If cylinder bores are confirmed to bepolished, then refer to Specification, Cylinder Block for the cylinder bore diameter and finish. If not within specs, there is an option to install oversized pistons/rings. Refer to Specification, Cylinder Block for details. A repair versus replace analysis may need to be done due cost of replacing exceeding the cost of new. All normal warranty processes must be followed.
Confirm the hours on the oil. If the oil excessively exceeds 500 hrs, then follow the oil change interval and obtain an oil sample to confirm if fuel dilution still occurring prior to the 500-hour oil change interval.
If there is a 523602-0 High Frequency Regeneration Code and no codes for high or low voltage for the DPF Differential Pressure Sensor (3251–3 or 3251–4), this may be due to the DPF requiring cleaning.
If the DPF has 3,000 hours or more, it needs to be cleaned as per the scheduled maintenance from the OMM and is customer responsibility.
If the DPF has less than 3,000 hours, confirm that the engine oil is low ash oil and Ultra Low Sulfur Diesel (ULSD) is being used as per the OMM. (Not using low ash oil or ULSD will cause the DPF to prematurely plug and would be a customer responsibility).
If there is a 523602-0 High Frequency Regeneration Code and active or logged codes for High or Low Voltages for the DPF Differential Pressure Sensor (3251–3, 3251–4), then replace the engine harness.Note: These codes are likely indicating a fatigue failure for a wire or wires in the DPF Differential Pressure Sensor. This can cause a faulty intermittent high DPF Differential Pressure reading, which will cause the ECM to incorrectly think the DPF is full.
If there is a miss, stumble, runs rough or is unstable, then the fuel dilution could be from an injector sticking open. Refer to the Troubleshooting manual and follow steps for "Engine Misfires, Runs rough, or Is Unstable". For those symptoms or low-power complaints thoroughly troubleshoot the low-pressure fuel system since that is THE MOST COMMON ROOT CAUSE for those symptoms.
Table 2
Wheel Loaders And Integrated Tool Carriers
Model Low Medium High
- liter (U.S. gal) liter (U.S. gal) liter (U.S. gal)
906M 0.0-4.2