Find out how to avoid expensive repairs to your outboard motor in this quick guide from James Cullen of Stones Corner Marine in Brisbane.  We join James in the workshop and through a client’s motor that is in for repair, James shares an example of what can happen to your motor if not flushed properly after use in salt water

See What Happens When You Don’t Flush An Outboard Motor Properly

It does not matter what brand of outboard you own all outboards can suffer the same damage if not flushed properly. I will show you the internal of an outboard that is suffering from lack of proper flushing. This customers engine has stopped running and we are going to show you why and how this could have been avoided. But first…

How does the motor cool – understanding the process and what causes the problem

An Outboard motor cools through water flowing through the engine and that water flow is supplied by the water pump in the lower unit up through a water tube and into the block of the engine. In that block the water runs through a series of water galleries, those galleries can be likened to veins and arteries in the body. Blockages that we find in the outboards for salt corrosion and sand are no different from cholesterol.

Incorrect or lack of flushing results in …

What we find is if you do not flush your motor as per the manufacturer’s specifications you will over time get a build-up of residual salt, and that salt will crystallize in the water flow galleries and being pressed against the alloy structure of the head they will slowly corrode and pit.

This will then build up until the water galleries are completely blocked, for example in the video above and image below you can see a complete blockage of salt and corrosion in this part of the head which is stopping water flow around that top piston. You can also see around the anode quite a bit of salt. That all needs cleaning out for the engine to have proper water flow to keep it cool.

That example was the good side of the motor, check out the next image of the other side of the motor which is completely blocked. Full of salt build-up and even sand which is a result of not only not flushing the motor correctly but also running the motor through the shallow water pumping a lot of sand up through the outboard.

What problem does this corrosion cause

So the problem with all this corrosion and the sand blockage is it does not allow the water to flow and cool the motor resulting in the motor overheating. The ultimate result of overheating is engine failure which triggers other expensive damage to the motor.

Will this motor run again and how?

Fortunately for this customer motor, the scorings are still good, no scouring or marks on the bores so this engine will run again. To achieve this we will be cleaning all the corrosion and sand out and replacing all the gaskets. Not only on the head but we will also do the side plate inner and outer gaskets, we will lift the engine block to replace the base gasket, replace the thermostat and water pump kit…which all comes at a cost that is avoidable if you were to flush the motor properly.

How 15 mins can save you hundreds $$$ !!

We have customers telling us they flush their outboards thoroughly, thoroughly to them is about 5mins which is just not long enough. Yamaha recommends a min of 15mins flushing after use in saltwater and we would assume most other outboard manufacturers recommendations would be the same…If you cheat your outboard flush it will cost you.

The final tip for those looking to buy a 2^nd hand outboard

Be sure to run that outboard before buying and check its temperature (refer to the manufacturer of that motor for optimal running temp info if unsure). You do not want to end up with an outboard that has corrosion build up in the motor because it’s going to cost you money immediately to be reliable on the water. If in doubt then next time your in for a service get the technicians at your local dealership to run a temp test with their Thermo laser guns as we offer here at Stones Corner Marine.

Let’s hope with better flushing process you to can avoid the problems and costs this client has now incurred. Thanks For watching James Cullen, Stones Corner Marine. Address: 117 Old Cleveland Rd, Greenslopes QLD 4120 – WEBSITE HERE

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