Check Engine Oil Level
To determine if there is enough oil or oil of sufficient quality to operate the injectors.
Check oil level with dipstick when vehicle is on level ground. If there is no oil or very little oil in the crankcase, the injectors will not operate.
If the oil level on the dipstick is overfull, it is possible the engine was incorrectly serviced or fuel is diluting the oil and filling the crankcase. Usually if a substantial amount of fuel is in the oil, it will have a fuel odor.
Inspect oil for color. A milky white oil indicates possible coolant contamination and will have an ethylene glycol odor.
Check service records for correct oil type and viscosity for the vehicle operating temperature. Single weight or 15W-40 oil is not recommended for cold ambient temperatures. Synthetic 5w-40 oil is recommended for cold ambient temperatures. Oil that has had extended drain intervals will have increased viscosity (become thicker) and will make engine cranking more difficult and starting less reliable at temperatures below freezing. Refer to the lube oil chart in the service manual or operator’s manual for the correct oil selection for temperature conditions.
The level in the oil reservoir should also be checked. Remove the inspection plug on top of the reservoir and check to see if the oil reservoir is full. (A reservoir that drains back after the engine has not been operated for a period of time can cause a hard start and die condition.) Filling the reservoir will allow the system to prime faster facilitating starting.
- Oil level low — oil leak, oil consumption, incorrect servicing.
- Oil level high — incorrect servicing, fuel dilution from fuel pump, fuel dilution from injector O-rings.
- Oil contamination with coolant — oil cooler, head gasket, cylinder wall porosity, cavitation.
- Low reservoir level — engine built dry (not pressure lubed), prolonged period of not running, leaking check valve in high pressure pump, excessive cranking without starting.
1/4-inch drive ratchet or breaker bar to remove inspection plug on top of the High Pressure Oil Pump (HPOP).
What’s ironic here is when the 6.0 and 6.4 Power stroke engines came out all I heard was negative comments about the 7.3.
Looking back the 7.3 has survived better than either of the smaller and newer engines. I won’t even consider anything diesel other than a 7.3