Rotax four stroke aircraft engines have proven themselves as reliable pieces of machinery. They can be bought as experimental (UL), sport (S) or certified (A and F) engine and there are four main models (fuel injected too: i models) to date. The original engine is the 80 hp 912, from which the 100 hp 912S was developed and Rotax also has a 115 hp turbocharged 914 engine. In 2015 BRP-Rotax announced the fuel injected 141 hp turbocharged 915iS.
To install and use Evans Waterless coolant the correct procedure must be follow to make sure no water is left inside the cooling system of the engine. The instruction manual from Evans describes this in detail.
Rotax Waterless Coolant from Evans.
Excerpt from the document:
Let the engine cool, set the heater control on maximum, and open the radiator drain. As soon as the expansion tank is empty, remove the radiator cap. On vehicles with block drains, remove the drain plugs and break through any sediment, which may be blocking the drain. Inspect drained fluid for rust and scale, if found flush as required (See Flushing and cleaning). For vehicles without block drains, remove the lower radiator hose at the radiator, remove the radiator drain cock and elevate the vehicle as required to drain the system To insure complete removal of old coolant, flush with Evans PREP fluid, or use the hot-purge procedure.
CAUTION: Ethylene glycol is poisonous. Do not leave it in an open container. Always use a drain pan to capture all fluid in compliance with local, state and federal laws. If drained fluid contains ETHYLENE GLYCOL, it must be disposed of as HAZARDOUS WASTE.
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