Repairing a Cracked Engine Block

I am the proud owner of a 1993 Bayliner Capri. I purchased this boat new and have been the only owner. I perform all my own maintenance on my boat, including winterizing each year.

Cracked Boat Engine BlockAbout 10 years ago, I forgot to winterize the boat, and in the spring, when I took the boat out for the first time that season, water was leaking through two large cracks on my engine block. The water that was still in the water jacket areas of my engine block had frozen during the cold winter months and cracked the block. I was sick about it, thinking that I would need to buy a new or rebuilt engine.

After doing some research on the Internet about repairing engine block cracks, I discovered that a lot of farmers have used an epoxy to repair cracked engine blocks on their trackers. This was encouraging knowing that there was an alternative to replacing the whole engine.

Studying how others did the epoxy repair, I learned that the most important part of the process was in the preparation of the surface to be repaired, that it needed to be clean and somewhat roughed up to give the epoxy a good surface to adhere to.

So here is the process I followed to repair my cracks:

I took a small grinder to the surface around the cracks to rough it up. Then I used acetone and cleaned the surface thoroughly, using a lint-free rag. After mixing up a batch of JBWeld epoxy, I  aggressively applied the epoxy to my two cracked areas. I tried to build it up enough so that I had about a 1/4 inch layer of epoxy. I let it cure for 48 hours.

Now 10 years later, those two areas are solid and have not leaked one single drop. I’m a big supporter of epoxy applications for minor engine block cracks.