One of the main reasons they do not install showers as OEM equipment, we were informed, was that Mercury Racing designs its drives to handle a certain horsepower range and the temperatures associated within that range, in typical -boating environments.
Paul Kermis, president of Simrek Corporation, based in Henrietta, NY, is one of the leading exponents of the need to install drive showers.
"We've had people come to us, complaining about white chalky deposits on the top half of their stern drive. Basically, this means that the casing of the drive is hot enough to boil off the water splashed onto it. This results in mineral deposits baked onto the drive. The higher the heat, the more deposits. Paint discoloration is another sign that your drive is running too hot, so is a cloud of steam you'll see every time your boat comes off plane. The extreme shift in temperature, from hot to cool, can damage an engine's metal components. It's especially harmful to aluminum, if the range is extreme."
Casing aside, drive components do run much hotter. Test results show that some stern drives operate higher than 350 degrees Fahrenheit.
Enter the drive shower, a device that distributes a continuous supply of cool water to a stern drive's upper half. Test results speak for themselves. The cooling generated by drive showers can reportedly double the bearing and service life of the drive oil by lowering an operating temperature of 220 to 350 degrees Fahrenheit by 30 percent. Kermis explains that this reduction in heat prevents oil foaming, a primary cause of oil breakdown which can lead to drive failure.
"It also reduces the thermal shock that occurs when the hot drive is plunged into cool water every time the boat comes off plane. This applies to nearly every boat, but it's especially prevalent in high performance applications."
Thermal shock, incidentally, is a condition that exists when metal, for example, is heated up and then cooled quickly, resulting in rapid expansion and contraction. Drive casings are made of cast aluminum that can develop small stress cracks if frequently subjected to thermal shock. Bearings and gears inside the drive could also undergo excess wear.
There are several designs of drive showers, most target the top bearing cap. One is a solid tube design with and without a bearing cap plate. The sold tube system sprays water at the top surface of the drive from a 1/2 inch diameter tube located at a 90-degree angle to the top the drive, about a 1/2 inch away. The flexible tube system with an optional bearing cap plate directs water at the top bearing cap at almost a 180-degree angle, causing the water to skip over the top of the drive.
The Simrek Multiport system makes use of two pick-up ports, targeting the top and two sides of the drive, Test reports indicate that drive showers are well worth the price. Installation is easy. Simrek boasts it takes only 15 minutes or so to make their system operational, others may take longer. Whatever the case, or whatever system you decide to buy, the fact that drive showers do their job well is best said by the individuals who actually have benefited. Simrek, for one, has an excellent track record. Users such as High Torque Marine, Advantage Marine, Twisted Styx (and chyx) race teams as well as the U.S. Customs Service are believers.
Dennis Lozito, president of Oakland Park, Florida-based Community Auto Marine concurs.
"We had a 1999 45-foot Wellcraft Excalibur with signs of serious overheated drives. We installed a Halo drive showers and Gaffrig temperature gauges. We also changed the drive oil to Amzoil Synthetic Gear Lube. We tested the boat with the drive shower eliminated on the starboard drive and found as follows:
Each test was run over a three mile area. Your drive showers have solved the problem. There is no more discoloration on the top of the drives."
CONCLUSION
There's no doubt that drive showers reduce drive temperatures. We don't really have detailed long-term tests to associate temperature reduction with drive component life and reliability, but we do know for a fact that there is no good reason to add heat to drives and lots of reasons to keep them cooler. Drive showers are not expensive, easy to install and an advantageous preventive measure. As always, the final decision is up to you.
This article by Peter Tasler appeared in the Volume 4 Number 2 Year 2000 issue of Poker Runs America Magazine. The pictures that accompany the article have been removed in order to save space, though the content remains unaltered. Please refer to the magazine for the article as it was published in its entirety
