Low Water Pressure Caused by Sand

A customer recently complained that the water pressure in their engine was getting weaker.  This became very evident when the motor was started - the water pressure gauge was barely reading at running RPM.  Upon inspection, sand was found present around many of the hoses near the powerhead.  It was possible to blow through the hoses and passages, but the water pressure was still low.

The next step was to start removing covers to see what was behind them - and the problem was obvious.  Sand was heavily compacted under all of the crankcase covers, as well as under the powerhead in the adapter.  Apparentlty, the boat had been power-loaded while being put onto a trailer on a very sandy lake.  Judging from the amount of sand in the passages, power-loading may have been a common practice.  Luckily, this issue did not end up with catastrophic engine failure, but gaskets, every cover the water pump and its housing all had to be replaced.

Flushing the engine is an essential step after running a boat in any type of water, even freshwater.  Flushing an engine helps to get rid of all the debris and dirt from lake or ocean, including sand.