Cracked block repair update

[westmich]

So I read some of your posts and repaired my cracked block with JB Weld (1997 Mercruiser Alpha One on SewaRay 175). Roughly 8-inch crack just behind manifold, used grinder to V it out and cleaned well with acetone. 2 days later I just took the kids tubing and the crack appears to be holding well. Thanks for the tips, folks, you saved me a few thousand sheckels (at least for now!).

Of course, now I have a new leak where the elbow attaches to the manifold--I replaced the gasket but there is about a 1/4 inch leak. Caulked it for today just to get on the water but tomorrow need to fix it for real. Any tips for more successful gasket replacement? Thanks again from West Michigan.

 

[P 0 P E Y E]

Re: Cracked block repair update

Congrats on the JB weld engineering science achievement badge. It is a rite of passage I once read somewhere. I think it was on a fortune cookie.

Now for the new leak.

Clean up the general area of the new leak to allow for a detailed inspection and identification of the actual problem.

If it is the mating surface of the riser (mixing elbow) the right way to repair it is to take the components apart, clean, inspect and probably replace worn or damaged parts. That being said, you may be on the last season of this cast iron and choose to perform a non-conventional repair.

Depending on the amount of water leaking, you may use the rain gutter method of collecting the water and channeling it away from the engine by means of rubber hose, old floor mats and bailing wire.

 

[westmich]

Re: Cracked block repair update

Thanks, Popeye. While I am unlearned in the bailing wire and rubber mat school of water misdirection, I am a quick study of fortune cookie philosophy and solutions.

My guess is that I didn't get riser and manifold surfaces clean enough and there is still some old gasket on one creating a surface gap. The gasket basically became one with the metal surfaces and I didn't grind it down very well. I'll do that first thing tomorrow and see if that fixes it.

 

[Bondo]

Re: Cracked block repair update

The gasket basically became one with the metal surfaces and I didn't grind it down very well. I'll do that first thing tomorrow and see if that fixes it.

Ayuh,... A few strokes of a flat file will tell you how ready it is..

 

[westmich]

Re: Cracked block repair update

Had to chisel the old gasket from the metal surfaces then file the surfaces flat and replace the gasket agaun. After 12 years the gasket had become one with the metal surfaces, and had become the same color makign it har dto tell if it was all off without taking itdown to new metal.

No more leak. If a few tiny chips of old gasket or dust from the paper filings fell into the manifold, what kind of harm will that cause? I don't think any chips went in but some dust probably did, try as I did to keep it out.

 

[westmich]

Re: Cracked block repair update

Had to chisel the old gasket from the metal surfaces then file the surfaces flat and replace the gasket agaun. After 12 years the gasket had become one with the metal surfaces, and had become the same color makign it har dto tell if it was all off without taking itdown to new metal.

No more leak. If a few tiny chips of old gasket or dust from the paper filings fell into the manifold, what kind of harm will that cause? I don't think any chips went in but some dust probably did, try as I did to keep it out.

 

[westmich]

Re: Cracked block repair update

Had to chisel the old gasket from the metal surfaces then file the surfaces flat and replace the gasket agaun. After 12 years the gasket had become one with the metal surfaces, and had become the same color makign it har dto tell if it was all off without taking itdown to new metal.

No more leak. If a few tiny chips of old gasket or dust from the paper filings fell into the manifold, what kind of harm will that cause? I don't think any chips went in but some dust probably did, try as I did to keep it out.

I have run the boat for a season now without a drop of water from the leak. I was skeptical but it really did the job nicely.

 

[muc]

Re: Cracked block repair update

Thanks for the update.
Good Luck Muc

 

[TrybalRage]

Re: Cracked block repair update

That's awesome. I'm heading out today to make the same repair on my 3.0L. Glad to hear some positive results.

 

[Howard Sterndrive]

Re: Cracked block repair update

Good to hear. JB weld and other metal-compatible epoxies are very handy. should mention the OP's engine is probably a 3.0 with an external crack only, just so the V6/V8 folks don't dig this thread up and try JB internally in a Vee engine