Oil not getting up to motor reservoir 2002 EFI 225

[chsapeak]

I've been chasing this problem all season and just cant figure it out. My oil reservoir on the motor does not get any oil from the onboard tank. Here's what I've done so far: replaced the check valve on the crankcase (which provides air pressure to the bilge tank) Removed and cleaned the pickup screen in the bilge tank itself, cleaned the bilge tank out and replace old oil with new, changed the inline filter just before the engine oil tank, checked the 3psi blow off to be certain its letting oil through to the engine tank. Now as far as hands on work, removed the line from the crankcase check valve and blew into it, doing so allowed me to see most importantly that my tank was holding pressure which it is, also I was able to move oil all the way up into the engine tank. It appears to me that the crankcase does not produce enough pressure to push the oil through my system. Is this possible? My motor is super strong and only has 280 hours on it. If this is the case how do i address this? Running 15 minutes at wot then having to stop and manually fill the motor's tank sucks...

Thanks

Serial number OT528359

[rdiesel01]

I chased the same problem at the beginning of the season - turned out to be the brand new check valve was defective

[chsapeak]

I removed the new check valve and blew through it freely in the direction of air flow, flipped it around and the valve seams to hold

[EuropeanAM]

Could also be a compression or reed problem on the bottom cylinder (#6).

[digthemup]

I removed the new check valve and blew through it freely in the direction of air flow, flipped it around and the valve seams to hold

Did you test with a vacuum gage to see how much pressure you are getting from the crankcase?
I can't remember correctly, but I think it is 5psi. However, Don can tell you for sure, since he is the one that told me.
BTW, where did you buy your valve? hope it's not a cheap fake. Get it from European to make sure you bought a good quality 1.

[chsapeak]

I put a pressure gauge on it the other day and all the needle does is jump like crazy, looks like it goes up to the 3-5 psi, but it doesn't stay up there. Like it's pulsing pressure. And the valve came from my local Merc dealer original Merc valve

[digthemup]

I put a pressure gauge on it the other day and all the needle does is jump like crazy, looks like it goes up to the 3-5 psi, but it doesn't stay up there. Like it's pulsing pressure. And the valve came from my local Merc dealer original Merc valve

If the gauge is swinging the needle both side of the "0", your check valve is bad, since it is sucking and blowing, which remind me of this old college girl I knew long time ago.
It should pulse to the "+" side about 5psi

[chsapeak]

It does stay on the plus side, does not drop into negative territory.

[JAZII]

check boat oil tank for cracks at the fill fitting, especially if you have remote oil fill.

Pressurize boat oil tank to 5-7 psi and see if it holds.

[digthemup]

It does stay on the plus side, does not drop into negative territory.

If it pulses on the '+' side only, the gauge is good, which is doing what it is supposed to do every other stroke of the motor. Check pressure at the hose at end going into tank, since you may have a crack or hole in hose. If it shows as good, check the hose as it attaches to the check valve before the onboard tank, and it should read about 3 psi. If it doesn't, check hose for leaks and tank/tank cap and remote filler hose and cap for holding pressure.

[EuropeanAM]

check boat oil tank for cracks at the fill fitting, especially if you have remote oil fill.

Pressurize boat oil tank to 5-7 psi and see if it holds.

Gearcase pressure tester, or a bicycle pump can be used for this purpose (disconnect pressure hose from crankcase pressure fitting and connect your pressure tester there). Should not be any leakage (you can check caps, connections, o-rings, etc. with soapy water).

[digthemup]

Reckon I figured Don would jump in in due time with a real solution, and whatever Don says go with it.

[chsapeak]

Will do the bike pump and soapy water Friday morning.. Thank You.. Weird thing is that I can blow air into the hose that attaches to the check valve with my mouth and push oil all the way to the upper tank.

[EuropeanAM]

Will do the bike pump and soapy water Friday morning.. Thank You.. Weird thing is that I can blow air into the hose that attaches to the check valve with my mouth and push oil all the way to the upper tank.

You've either got healthy lungs, or you're full of hot.... Sorry, couldn't resist. But seriously... that takes some serious "push power"!