Technical Service Bulletin, TSB53018-C
If you ever experience repeated, low-hour failures of your HEUI pumps (fuel pumps) , there might be debris circulating within your fuel system. Accompanying fuel injector failures are also symptomatic of fuel contamination. Below are recommended areas to inspect for diagnosing your failure.
- Oil Filter Base Gasket – This gasket may break away or receive damage, which can cause unfiltered oil to bypass the filter by transferring unfiltered oil into the filtered oil chamber.
- Oil Cooler Flange – The oil cooler may be warped and not perfectly straight. Check this using a straight-edge and feeler gauge.
- Oil Cooler Gaskets – Be sure to check that the gasket properly adheres to the oil cooler flange, especially between filtered and unfiltered oil cavities.
- Oil Filter Base (Bypass Check Valve) – Check the bypass valve seat for porosity. If present, you will need to replace the Filter Base, Spring, Valve, and Oil Cooler Gasket.
- Check Valve Spring – Ensure that the oil filter check valve utilizes the most current spring design.
- Bypass Valve – Inspect the oil filter’s bypass valve to be sure that there are no leak paths evident on the seating area.
