cracked block repair

[38plymouth]

I have confirmed that my mercruiser 120 has an internal crack on the port side below the number 4 cylinder. It's right next to the rear frost plug by the drain valve. It's not a huge crack but it is enough to let water drain into the oil. There is a product called hard blok used in race car engines that fills the water jackets to make a block stronger. I'm wondering if I poured enough of this into the block and let it harden shouldn't it seal the crack and prevent the water leak? There appears to be plenty of room for water flow if I used an inch deep or less. Any thoughts or experience with this product? I figure I don't have much to lose if it doesn't work.

 

[motox6]

Re: cracked block repair

I have a pint of a similar product I was going to use, however my block was beyond repair. I could give this product to you for half of what I paid.

 

[f_inscreenname]

Re: cracked block repair

Good luck and don't go to far from shore. A little water in the oil and for the lack of a better term "you are walking" well swimming. I would start looking for a block now even if I did try the repair. I wouldnt be able to have any fun thinking my motor could lock up at any time. Also if you haven't done any damage already to the stuff inside except for the broken block wait till you lock it up running 3000rpm’s. There wont be much left to fix.

 

[38plymouth]

Re: cracked block repair

I already found another motor, I guess I'm just curious if this would work to seal a crack. Mine is a very small crack that I was only able to find by blowing air into the dipstick tube and pressurizing the the oil pan. There is just enough of a crack to blow a few bubbles under pressure.

 

[Jdeagro]

Re: cracked block repair

This is not my field of expertice but when I see these comprimises about to be made I feel compelled to say something. <br /><br />Keep in mind that the block cracked for a reason, usually stress. If it was due to freezing in the winter that is a whole different issue. Filling the water jacket to make the block stronger may be only part of the process. They can not run the motor without proper cooling, therefore you have to assume that they have also compensated for the cooling loss.<br /><br />If you run this boat in salt water you should know that it is criticle to make sure the boat does not run above 165 degrees F. Above that temp the salt will begine to crystalize and restrict all of the other passages. <br /><br />If you over heat the engine, you will create a host of other problems and many of the parts that you would use in another engine blocke may be dammaged. <br /><br />Don't comprimize is my suggestion.

 

[Walt T]

Re: cracked block repair

Internal cracks cannot usually be fixed. It will get worse if you continue to use it.

 

[38plymouth]

Re: cracked block repair

It cracked from freezing. I figured it was a long shot, but you never know. I think this stuff would seal ok but I am worried about the crack getting bigger from heating and cooling and eventually leaking again.

 

[Bondo]

Re: cracked block repair

The Stuff you're refering to is for Dragsters.....<br />Where Cooling Isn't an Issue......<br />It's Actually Concrete.......<br />It's Not for Sealing, AnyThing.......<br />Scrap that 120hp,+ Drop in a 140hp.........<br /><br />BTW, the price of Scrap Iron is Really High, right now............

 

[denniz]

Re: cracked block repair

Ditto, you will have no water jackets if you use it.