Mercruiser Cracked Block Symptoms

In order to know for sure you’ve got a cracked block, you will need to remove the engine and have it checked professionally. However, there are some Mercruiser cracked block symptoms that can let you know in advance about if your block got cracked.

Mercruiser Cracked Block Symptoms Img1

Before we start, it is important to know that finding water in the oil can be one of the symptoms, but not the definite one since other problems may have caused it.


Undeniable Symptoms

Water In The Bilge

First of all, make sure the water found in the bilge isn’t there because it has rained. Although boats may be waterproof, sometimes water finds a way to sneak into curious nooks and places where it's not supposed to be.

So, the first step is to verify if rain was to blame for the water in the bilge. If it wasn’t, unless someone has accidentally spilled it there, the news isn’t hopeful at all and you seem to have a cracked block.

The Oil Doesn’t Have Good Aspect

Have a look at the oil. If it doesn’t show the shiny aspect as usual, and/or if you notice it’s dirty, opaque or doesn’t seem pure, there's a high likelihood that your block was cracked.

The Boat Isn’t Running Good

No one knows your boat better than you. If you're steering another person’s boat, you may not realize a cracked block just by taking it for a ride over the water.

However, when it’s your machine, you can feel that something is not running as smoothly as usual.


What must I do?

First of all, don’t take each of the symptoms separately; only experiencing one of them isolated can be for several different reasons not related to a cracked block.

Mercruiser Cracked Block Symptoms Img2

The problem may be if you experience more than one of them, especially three or more.

To finish confirming your suspicions, pay attention to the apparition of white smoke as the engine is working. A dead giveaway would be flying pieces of metal.

If it’s confirmed that your block is cracked, you’ll have to remove the engine and seal or patch the cracks on the block.


Thanks for reading. On another note, if you want to learn a bit about wooden boat building, go here.

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License