Low oil pressure after boat was not started for two years
07-07-2021 | 06:24 PM
#1
Thread Starter
Registered
Joined: Nov 2012
Posts: 141
Likes: 39
From: H.B. CA
Low oil pressure after boat was not started for two years
Two motors, when the boat was last ran the oil pressure was 70 psi. both motors. Just changed the oil and started the boat and now the starboard pressure is 20 psi at start up idle. If I rev it up it go's up to 80 psi. So I put it in the water to test and oil pressure went to 0 psi after about 5 minutes, bumped the throttle and it and it went back up to 20 psi. Took the boat out of the water and put a mechanical gauge on the oil cooler block to check the electric gauge and pressure was the same 20 psi. The motor is not tapping or knocking, sounds fine. Then I thought the oil pump pick up fell off the pump so I added several quarts of oil to bring the level up with no change in pressure.
What could cause this?
What could cause this?
Last edited by Seahawk 2000; 07-07-2021 at 06:26 PM.
07-07-2021 | 07:31 PM
#3
Thread Starter
Registered
Joined: Nov 2012
Posts: 141
Likes: 39
From: H.B. CA
The reason you add oil is to get the level up past the oil intake on the pump and pressure would be good if the pick up fell off, then drain the excess oil, just at test.
07-07-2021 | 07:43 PM
#4
Registered
Joined: Oct 2005
Posts: 1,073
Likes: 251
From: Waldorf, Md
I have seen oil pump relief valves stick open after sitting a long time. I think they get surface rust in the bores and then as soon as they open they stick that way. The fact that it goes up to 80 when you increase the rpms would somewhat verify this too.
07-07-2021 | 07:44 PM
#5
Registered
Joined: Oct 2005
Posts: 1,073
Likes: 251
From: Waldorf, Md
07-07-2021 | 08:00 PM
#6
Thread Starter
Registered
Joined: Nov 2012
Posts: 141
Likes: 39
From: H.B. CA
Are you talking about the pressure regulator on the pump or the pressure relief valve in the block or oil filter block?
07-08-2021 | 05:36 AM
#8
Registered
Joined: Oct 2005
Posts: 1,073
Likes: 251
From: Waldorf, Md
One thing that I would do before running the engine any more is to take the filter off and cut it open and check for metal. Just in case something else is failing and causing the problem.
07-08-2021 | 08:07 AM
#9
Forum Regulator
Joined: May 2001
Posts: 24,203
Likes: 1,592
From: Worldwide
The one in the oil pump. The one in the block really has nothing to do with oil pressure.
One thing that I would do before running the engine any more is to take the filter off and cut it open and check for metal. Just in case something else is failing and causing the problem.
One thing that I would do before running the engine any more is to take the filter off and cut it open and check for metal. Just in case something else is failing and causing the problem.
...I did NOT cut the oil filter open on my race car when I changed it last month. I need to do that.
