2005 150 XR6 oil check valve?

[drl2t]

I've been doing some preventive maintenance recently and noticed air in the clear line between the oil check valve and the oil pump. When it's hot outside, I can see fuel bubble up into this line from the tee connector. I assume that indicates this check valve is bad?

Hoping this attachment works--it's the brass valve at the top of the fuel T-connector

IMG_20190805_120102.jpg

Thanks


2005 Mercury 150 XR6
Serial # 1B042145

[JOE54]

needs new one sir for sure if fuel is bypassing

[drl2t]

Thanks. I have 1 more question about this--

What should be in that line? Oil only? Air and oil? Air only? I've been reading a lot about the oiling system, and it appears there is a check valve that is intended to let air in--just not sure if it's this particular valve or not.

[EuropeanAM]

Oil ONLY. Oil injection will need to be bled to remove ALL air from that line before running on straight fuel (premix until you know it's properly bled).

[Stubborn Hook]

There are three check valves in the oil system. One between the clear oil tube and fuel tee, one screwed into the side of the block, and one up at the oil reservoir on the motor. The one in the fuel line and in the block allow the oil feed system to work. The one at the oil reservoir is only there to allow air into the oil reservoir so that it can keep providing oil if there is an obstruction in the feed line from the boat mounted oil tank.

I too noticed air was in the clear oil tube on my 03 XR6 earlier this year, so I replaced that check valve and the one in the block. I left the one at the oil reservoir alone, but it's easy to change that one too.

Also check the level in the oil reservoir on the motor. Mine had gotten an inch low from that leaking check valve and was causing the oil level alarm to beep when hitting waves. You can even shine a flashlight through the tank and see the level when it's that low.

Since replacing the two check valves and refilling the oil reservoir, I haven't had anymore of those issues. The clear oil line stays full of oil now when the boat sits. It also no longer smokes heavily upon start-up. The old leaking check valve was allowing oil to accumulate in the fuel line as the boat sat, then when you fired it up, it had to burn through that slug of oil rich fuel in the line.