Antifreeze mixtures that contain more than 50% glycol can cause overheating problems with fresh water cooled Indmar engines.
A consumer that is experiencing high engine operating temperatures or overheating when operating at higher speeds and loads, may have too much glycol in the mix. Other issues could also be the problem; water pump impeller, pinched hose, intake water obstruction, etc.
Indmar dyno testing has shown that mixtures with more than 50% glycol raised coolant temperatures. As the mixture of glycol to water was increased, the risk of overheating the engine was even greater.
Indmar uses Sierra propylene glycol for health and environmental reasons. Propylene glycol is as good, if not better than ethylene glycol. For more information and the benefits of using Sierra propylene glycol, go to www.sierraantifreeze.com/benefit.html
What Happens When Mixture of Glycol to Water Increases?
Freezing point of mixture decreases
Boiling Point of Mixture increases
Ability to transfer heat decreases