Mercruiser 3.0 - Block rust

gone_walkabouts

Recruit
Joined
Feb 7, 2022
Messages
5
Have a Mercruiser 3.0 around a 2004 model and there is alot of rust appearing on the Block.
Looks to be worse around the head gasket and may be the source ?
With good compression, could this be a built of salt water over time that has done this or could a leak in the head gasket trickly salt water down the block ?

Any thoughts on this ? Any one else seen similar ?not to keen on replacing the head gasket but might be the fix >
Block rust.jpg
Paint has peeled off.
Compression and performance of engine fine at the moment.
 
Last edited:

Rick Stephens

Admiral
Joined
Aug 13, 2013
Messages
6,118
Are you where you can run it on muffs for a bit? Let 'er get warm and see if you have a leak.

That side is not the normal one to have any kind of freeze damage. So headgasket or just paint falling off.
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
42,067
If you have not seen water, then it might have been just a bad paint job.
 

gone_walkabouts

Recruit
Joined
Feb 7, 2022
Messages
5
Yes - warmed it up and no water seen from area. Yes think it was a bad paint job that has peel and rusted. Thanks all for input.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,958
Ayuh,...... Welcome Aboard,..... What's the chances, that the motorbox leaks right about there,......

Donno how many I've seen, that drip right on top of the carb,.....
 
Top