[thebobber]

Buying a boat with the blue water 1999 mercury 250 efi. Compression checked out, gears seem smooth, runs strong. There is however a noise. I am not used to mercury engines and wondered if someone could help. When running (idle on up) there is a sound like a berring or other internal parts moving. It does not sound like a knock, but again like you here parts moving. Can anyone help? Do all the mercs sound this way? Should I not buy it?

Thanks for any and all help!

[Don S]

There ARE parts moving....... Sure you aren't just hearing injectors clicking? ? ? ?

Might want to get a Certified Merc tech to check it out, since it's IMPOSSIBLE to describe a sound like what you are trying to describe.

Might just have them check the engine and lower out to make sure it's worth buying.

[thebobber]

"There ARE parts moving"

Of course but should I hear individual parts?

I am buying from a dealer who says it is supposed to be that way. Getting another merc guy to go to their dealer would be a challenge!

On antoher forum I got this:
"My engine sounds different throughout the rpm operating range as I run it. It does have an interesting sound signature, almost a "metal on metal" or rattling sound when she runs."

Any other input? What do you guys think?

[gss036]

You should be able to place your ear on top of the cowling and hear a bad bearing roll. Or, take the cowling off and place a stick against the block and listen. A lot of mechanics will use a stethscope, like doctors use, to listen.
If you are running a stainless prop, there could be a little noise at idle and low speed, but definately not powering up.
I know that when I lost a bearing and the rod came through the side of the block it sounded like a metal coffee can with a bunch of marbles rattleing around.
Better yet, ask the dealer if he is willing to give you a written warranty to cover it if there is something wrong.

[thebobber]

Figured it out. On the engine cover itself two of the little rollers were spinning free and echoing big time. Guess my hearing is working well! Long story short, no problem anymore!