Can anyone tell me what this noise is

[cshep215]

I have a 2000 Sea Ray express cruise 215. The engine was rebuilt in 2011 and after a good day out as we can back to the marina it started to make a high pitched buzzing noise. When I pulled the cover it sounded like it was coming from the back of the engine almost like air buzzing through a line. Has anyone else experienced something like this? I have attached a video to this post.

[pesarsten]

I don’t see your video

[StuM]

"Forum Tech Support and Site Help" is for help with using CF. You will probably get a better response if you post in an appropriate area such as one of these:
https://www.cruisersforum.com/forums/f11/


And I don't see any video either

[cshep215]

Obviously I am new to the forum once I figure out how to get it to load I will get it posted. Thanks

[PirateGuy]

Right now without the video (with sound) what you are verbally describing matches the sound my engine warning buzzer makes. Of course, this is at the control panel, and not at the rear of the engine.
Do you have any other warning buzzers? High water? Propane?

[cshep215]

It’s definitely not coming from the control panel. But the noise does sound familiar to some sort of electronic buzzer. The noise is very similar to the sound the fuel pump makes when you first turn the key to prime the injectors. It is definitely coming from the port side near the back of the engine. It’s a bit lower pitch but still distinctive at idle. When I throttle up to 3200 RPMs for a few seconds and throttle back the noise is a bit higher pitch and quite noticeable. All my gages read normal and am not getting any warning siren. Engine stays at 175 degrees, oil pressure is fine and no other knocks or miss fires front he engine itself. Hopefully I can figure out how to get the video uploaded.

[cshep215]

https://m.youtube.com/watch?v=ckgCXtTAZkg

Hopefully this link will load the YouTube video I made so you can here it

Thanks

[Boatyarddog]

Originally Posted by cshep215

I have a 2000 Sea Ray express cruise 215. The engine was rebuilt in 2011 and after a good day out as we can back to the marina it started to make a high pitched buzzing noise. When I pulled the cover it sounded like it was coming from the back of the engine almost like air buzzing through a line. Has anyone else experienced something like this? I have attached a video to this post.

As a repair tech, this sound is heard when high speed fuel pumps start to fail.
Your engine is probably fuel injected.
This is not a warning buzzer.
Also, check the fluid level in the power assist pump, use ATF if low do not overfill.
PCV valve in the valve cover if installed can buzz as well.
The pumps were probably not replaced when the rebuilt engine was installed.
SV Cloud Duster

[Scubaseas]

Sounds like a bearing maybe? Try taking the alternator belt off and see if the noise goes away. You can use a mechanics stethoscope or a long screw driver held to ear to listen to where the noise gets louder so as to isolate where the noise is coming from. Another diagnostic would be to remove the dip stick or oil fill cap when running and see if this alters the noise.

Does the noise stay the same with RPM?

Does it change on forward or reverse?

[cshep215]

We did forget to mention that the fuel pump was replaced about 3-4 yrs ago. But that doesn’t mean that is not the issue. I’ll also check the fluid levels. I don’t think it is a bearing. If you put you hand on the pulleys after its been running for a while they are not real hot. Nor does the sound seam like it is coming from any of them.

Thanks

[Boatyarddog]

Originally Posted by cshep215

We did forget to mention that the fuel pump was replaced about 3-4 yrs ago. But that doesn’t mean that is not the issue. I’ll also check the fluid levels. I don’t think it is a bearing. If you put you hand on the pulleys after its been running for a while they are not real hot. Nor does the sound seam like it is coming from any of them.

Thanks

Power assisted systems have pressure relief valves incorporated to keep pressure in the system relative to the effort placed upon the steering wheel.
Going forward you have little need for power assist, so the pump internally dumps pressure.
Glad you've changed out pumps, the high speed pump makes noise, if there are two pumps the low Speed pump is a transfer pump, and makes the boat feel as if it's running out of fuel.
Really wouldnt worry about it unless there are other symptoms.
SV Cloud Duster

[Scubaseas]

Originally Posted by cshep215

We did forget to mention that the fuel pump was replaced about 3-4 yrs ago. But that doesn’t mean that is not the issue. I’ll also check the fluid levels. I don’t think it is a bearing. If you put you hand on the pulleys after its been running for a while they are not real hot. Nor does the sound seam like it is coming from any of them.

Thanks

You can have a bearing going bad and not be warm to the touch. This a 2000, 220HP 5.0L Mercruiser with MPFI?

If there's a fuse for the high pressure pump or you can find the plug try cutting the power to the HP pump while engine running and see if the noise stops. Capt Obvious would point out the motor will stop running in about 3 seconds if you disable the HP pump but the noise if the HP pump should stop the instance you remove the power to said pump. If it is the HP pump making noise it's from the bearing in the pump itself which is not serviceable, you have to replace the pump itself.

Removing the alternator belt would eliminate coolant pump, alternator, idler bearings or PS pump if you have one as the source.

Opening the oil cap or pulling up the dip stick would rule out PCV being stuck (which can make the crank seals vibrate)

[Montanan]

Purchase a stethoscope at any automotive supply store and probe the components where you perceive the sound to emanate that will help identify the source. Then one has to determine why the source is making such sound.

Just be sure to avoid getting tangled with any rotating parts, e.g., belts.

Reference link:

https://www.bing.com/images/search?q...mageBasicHover

[Cadence]

Is the brass colored item next to the hose a valve that may be not seated and whistling?

[cshep215]

Originally Posted by Scubaseas

You can have a bearing going bad and not be warm to the touch. This a 2000, 220HP 5.0L Mercruiser with MPFI?

If there's a fuse for the high pressure pump or you can find the plug try cutting the power to the HP pump while engine running and see if the noise stops. Capt Obvious would point out the motor will stop running in about 3 seconds if you disable the HP pump but the noise if the HP pump should stop the instance you remove the power to said pump. If it is the HP pump making noise it's from the bearing in the pump itself which is not serviceable, you have to replace the pump itself.

Removing the alternator belt would eliminate coolant pump, alternator, idler bearings or PS pump if you have one as the source.

Opening the oil cap or pulling up the dip stick would rule out PCV being stuck (which can make the crank seals vibrate)

I will be back to the boat next Saturday to Try each of your suggestions. During all of this I did start hearing the serpentine belt occasionally skip and squeal so that definitely needs to be replaced. I did notice just before I left, for what ever reason when I hit the trim tap buttons the pitch of the noise dropped in tone and when the buttons were released the pitch of the tone went back up. I have never noticed the trim tab controls drawing power from the engine before. It didn’t not cause any change in the engine RPMs nor seem like it was drawing power from the engine itself but it did make a significant change in the noise.

Thanks