Oil prime

[DewRonInc]

when u do a oil prime how much oil is out of motor mounted tank and do u open vent on tank

[Savage]

Oil Pump Prime Sequence is performed with a CDS, or Diacom system. Tank vent cap is CLOSED.

[DewRonInc]

Yup that is what we did it did not seem to use as much oil as before just changed filters from air compressor

[DewRonInc]

we used cds

[Jtreed99]

Motor mounted tank vent should be OPEN, unless you used a gearcase pressure tester to pressurize the remote (boat) tank. If you used the motor mounted tank vent method you must bleed that tank full after the prime.

[DewRonInc]

Yeah, they did not open vent and it barely used any oil, I changed filters coming off of air compressor

[Savage]

You do not open the vent on the reserve tank for an "Oil Pump Prime Sequence", with a CDS!

[Bryanmc57]

You do not open the vent on the reserve tank for an "Oil Pump Prime Sequence", with a CDS!

You will normally either:

A: Pressurize the remote oil tank with a gearcase pressure tester

-or-

B: Loosen the cap on the ENGINE mounted oil tank

(while performing an Oil Pump Prime Sequence).

Service Literature recommends "A" primarily, but "B" will work as long as you bleed the air from the engine mounted tank when you are finished.

I'm confused. Isn't the engine mounted tank the reserve tank?

[Fishysam]

I'm confused. Isn't the engine mounted tank the reserve tank?

no the engine mounted tank is just a spot on its way into the motor where there is a low oil sensor to stop you from melting it down

[EuropeanAM]

Motor mounted tank vent should be OPEN, unless you used a gearcase pressure tester to pressurize the remote (boat) tank. If you used the motor mounted tank vent method you must bleed that tank full after the prime.

Service literature does recommend pressurizing the system similar to what it is when the engine is running (example used in literature is a gearcase pressure tester being used). This is critical if the lines from the tank to pump, and pump to engine are "dry" (if it's just a pump replacement and oil is right there at the pump, I prefer to open the cap on the oil tank and vent that tank so the oil pump can draw oil with little resistance).

There IS a tee-shaped check valve that is designed to allow air into the system if there is a SUPPLY RESTRICTION (so that the oil pump can consume the oil in the engine-mounted tank). My big concern is how many "counts" the new oil pump has to plunge it's brass sleeves and o-rings before oil supply fills the pump chambers (I prefer to keep that to a minimum).

JMHO though... Manual method is certainly an excellent method.