Mercury 240hp EFI inline Directional Oil Filter

[Racereddie]

Just going through the different Oil and Fuel filters in a 2003 Mercury 240hp EFI engine. In looking through the shop manual it could be read to believe that if you replace the Directional Oil Filter (located between the Oil tank and Oil Reservoir Tank) you have to prime the oil pump. Seems that replacing the filter would not break the integrity of the system from the reservoir tank to the pump and it does not give a method of priming the pump without owning a DIGITAL DIAGNOSTIC TERMINAL


Eddie

 

[WAJetboating]

Seems that replacing the filter would not break the integrity of the system from the reservoir tank to the pump and it does not give a method of priming the pump without owning a DIGITAL DIAGNOSTIC TERMINAL

You can always reprime the oil system by running on premix in an external tank for a few minutes until the oil system is primed up again. You need an external tank for proper winterization anyway.

 

[Racereddie]

Thanks, it is nice to know that it does not need to be pressurized to prime. I already have an external tank from the motorcycles just need to swap out the hoseline.

Side note thanks for the Oct 2010 post on the head temperature sensor "tune up". I got a new one off of ebay. I am going to replace the plugs, clean the internal fuel filters see how that goes then replace the sensor as you suggested. Your write up was great.

Eddie

 

[WAJetboating]

Thanks, it is nice to know that it does not need to be pressurized to prime.

The oil injection system works on crankcase pressure from the engine. Pressure runs from the crankcase to the large external oil tank, which drives oil back toward the engine and fills the engine-mounted tank. That tank then supplies oil to the on-engine oil pump, and thence into the VST for mixing with the fuel.

Side note thanks for the Oct 2010 post on the head temperature sensor "tune up". I got a new one off of ebay. I am going to replace the plugs, clean the internal fuel filters see how that goes then replace the sensor as you suggested. Your write up was great.

You're very welcome! Cleaning the internal fuel filters requires you to remove and disassemble the VST. Not a difficult job, but it will take some time. Pay attention to the little hoses, they're easy to mix up when reassembling.

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