Cracked Block

wpminc

Recruit
Joined
Jul 7, 2005
Messages
2
I have a '91 Mercruiser 3.0 I/O that appears to have cracked on the side of the block over the winter by ice. Pushed out slightly with tiny water dribble. Anyone know where to find a used block or if JB weld will fix? Any suggestions will be appreciated. :(
 

f_inscreenname

Commander
Joined
Aug 23, 2001
Messages
2,591
Re: Cracked Block

I have seen JB weld do some amazing things. Would I recommend it to someone publicly for a repair, no. But I would try it myself if I was desperate enough knowing that the block would have to replaced later. The thing that may hold me back would be thinking that I may cause more damage to the motors internals if the crack was inside also. Right now you are looking at a block, with a quick ride you could ruin the crank, cam, rods...... Unless it is a throw away motor I would fix it before I went any further.
 

DHPMARINE

Captain
Joined
Dec 16, 2003
Messages
3,688
Re: Cracked Block

If you only see a dribble out of the crack,and you don't have any h2o in the oil,you really don't have a problem.<br />The leak may eventualy rust up and stop.<br />In the long run it will look better (for resale)than if you slop it up with sealer.<br /><br />DHP<br /><br />JB-Weld is a great product when you need it
 

Scaaty

Vice Admiral
Joined
May 31, 2004
Messages
5,180
Re: Cracked Block

Try some JB "WaterWeld"....knead it up good, and slap it in the crack
 

MRS

Commander
Joined
Jul 10, 2005
Messages
2,579
Re: Cracked Block

I have a merc 120 I had bought from a friend of mine. He did not drain the manifold or block. So our first trip getting ready to go for a week wifes yelling at me because she thinks I love working on everything wright till the last second just to make her mad. I give one last check put on earmuffs turn on water start engine looks great sounds great open engine cover water coming out of two big cracks on the block so do not tell her wire brush the heck out of the block mixed J.B.Weld let dry all night spray painted black. We left in a.m. That was three years ago and still holding...
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,110
Re: Cracked Block

As long as the water is leaking Out of the motor,+ Not In to the Oil,.........<br /><br />The Epoxy Putty is the Best Answer,...........<br /><br />Every Welded Repair I've ever found had a layer of Epoxy over it to stop the rest of the Leaks........... ;)
 

f_inscreenname

Commander
Joined
Aug 23, 2001
Messages
2,591
Re: Cracked Block

Man some of you guys have big balls. Slap some sealer in it and don't look back, WOW. MRS, 3 years????? After the third ride the panic attacks would have been to much for me and the motor would have been pulled the next weekend. I guess none of you guys have broke down and when you looked around you didn't see anyone for miles.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,110
Re: Cracked Block

As long as it was leaking Out,..as I stated above,.........<br /><br />And,..As long as I had a dependable Bilgepump,+ was boating on a small inland lake,.....<br />I might even just Skip the epoxy till I found the time to Glue it up Right........But, I'd Still use Glue,+ Not my Welder.......<br /><br />Although I Agree,.....<br />Block Replacement is really the Only Proper Repair...........<br /><br />I've seen Glued Blocks last for Years,.........<br />Or until somebody Didn't Drain the block,.. And,.. Froze it Again.............
 
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