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Water can Cause Heavy Damage to Race Motors if it Freezes

NASCAR K&N SERIES Block Cracks from Freezing. 


Winterizing Your Race Motor Includes Draining the Water


Bill Maropulos owner of Bill Maropulos Racing builds many of the NASCAR K&N Series motors and for other racers on the west coast. (805) 520-4899. Bill supplied the picture and the information for this article.


At the end of the racing season, we tend to just to put the car away and forget about it for the rest of the winter. While this is time for us to relax, the car and its engine are still subject to the weather. Freezing weather may not be a problem in some parts of the country, but in others, freezes are a way of life for several months of the year.

Our passenger cars and tow vehicles use antifreeze, but in our race car motors rules forbid its use. In some parts of the country, a cold snap can happen suddenly even in late spring or early autumn. Race engines are at risk of cracking and breaking from freezing. Draining the water until ready for the next race to avoid serious problems like the one shown in the picture above.

As the water freezes the ice expands, and it places extreme pressure on the block and heads. The ice puts equal pressure on all parts of the engine until the weakest part breaks.The ice pulls the water passages apart, and the block eventually cracks at its weakest part. The cooling passage next to the piston sleeves is the most at risk.

Crack in block

In this photo from BMR, Bill Maropulos Racing, the coolant passages from the block to the heads have cracked. The block needs replacing, and the pistons are now trash from the rust on the sleeves. Image shows the damage that can result from water freezing in an engine. 

With older motors, the freeze plugs would pop out and allow for some pressure relief, but new motors like the LS2s  with aluminum blocks used in NASCAR’S K&N PRO SERIES do not contain freeze plugs. Fortunately, the heads do come with freeze plugs, but those still may not be enough to spare the heads from cracking.

It's bummer enough to lose a motor on the track during a race but to lose one to Mother Nature is another story. Race preparation extends beyond the track.


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