Mercruiser 3.0 Cracked Block

[kizziaj]

I have a Mercruiser 3.0 lx that has a cracked blocked due to my stupidity of not winterizing it this past winter. It just appears to be an wxternal crack approximately 5 inches long. Is there anyone with any cheap suggestions on how to fix it without having to replace the block. If I do need to replace the block is there any suggestions about where to purchase a block? I am hitting a wall everywhere I look. Thanks for anyones help.

 

[Bondo]

Re: Mercruiser 3.0 Cracked Block

Ayuh,... IF it's Only an External crack,... Clean it up,+ epoxy it closed....

 

[ENSIGN]

Re: Mercruiser 3.0 Cracked Block

Loosen the drain plug on the oil pan and see if any water comes out.If its milky looking or way overfull you're beating a dead horse and you can epoxy it till the dogs come home! If the blocks cracked,there's a good chance the manifold is.

 

[jerryjerry05]

Re: Mercruiser 3.0 Cracked Block

What year? The local junk yard might have a block.Like E said other stuff might be cracked too.J

 

[JustJason]

Re: Mercruiser 3.0 Cracked Block

What year? The local junk yard might have a block

Eagh... Maybe if you have a boat/marine boneyard, but those are few and far between. The 3.0 GM industrial engine thats in his boat was never used in an automotive application.

 

[kizziaj]

Re: Mercruiser 3.0 Cracked Block

There isnt any water in the oil. It is not milky at all and no water in the oil pan. I am going to Put some JB weld on it tonight and try it out tomoorow evening to see if it holds up. Thanks everyone for the responses and help.

 

[Chris2]

Re: Mercruiser 3.0 Cracked Block

I just went through this with a 305 V8 cost me 2200 machine work and all for automotive block and total rebuild and replace at a local mechanic (used the old crank, rods and cam) , dealer wanted 4000+tax, just glad I got in early spring got the boat back in time for summer now hes backed up with cracked blocks.

 

[zbnutcase]

Re: Mercruiser 3.0 Cracked Block

I just went through this with a 305 V8 cost me 2200 machine work and all for automotive block and total rebuild and replace at a local mechanic (used the old crank, rods and cam) , dealer wanted 4000+tax, just glad I got in early spring got the boat back in time for summer now hes backed up with cracked blocks.

You could have upgraded to a 350 for that kind of dough

 

[Chris2]

Re: Mercruiser 3.0 Cracked Block

not for 2200 at least not that I could find

 

[Shelby Ladner]

Re: Mercruiser 3.0 Cracked Block

I too have a 3.0 which was cracked just under the head/manifold in the center of the block. When I discovered mine I did what you are doing and asked this great forum where I found very useful information. I first checked compression and oil then I drilled 1/8" hole on each end of the five inch crack, cleaned well, and used "Marine Tex". After Marine Tex was fully cured I ran engine until warmed up and checked oil again. I've been running it for the past two years and it is still holding. I keep a check on the engine oil and bilge area after each outing.

 

[cr2k]

Re: Mercruiser 3.0 Cracked Block

Grind out the crack to a V to get better hold with the JB Weld. You want it to be a bead like a weld, not just slathered on top like a band-aid.