Outboard Motor Care

Outboard motor care is not a difficult task at all. After all, you have invested your hard earned money into this, so it makes sense to take care of it. You don't have to be a mechanic to keep your motor in good condition.

After each Use


  • The engine needs to be flushed of salt water after each use. This requires the use of a flushing adapter that seals over the water pump intake screens on the lower unit. These flushing adapters can be purchased from any boating store.


  •  Once the flushing adapter is in place & the garden hose is hooked to it, turn the water on & start the engine, allowing it to idle. Once the engine is running, make sure that the water is flowing through engine. If water is not coming out of the tell tail, there could be a number of reasons.
    • First of all check that the flushing adapter has a tight seal around the water intake screens & that the garden hose has sufficient flow.
    •  Second of all, check that the nipple or tell tail hose is not blocked. This can be checked by poking a wire up the tell tail hose or if you have access to compressed air, blow back through the tell tail outlet. It doesn't take much to block it up; generally a salt crystal or small piece of rubbish is enough to do it.
    • If you have been through the above check lists & there is still limited or no water flow, the water pump maybe the problem. If this is the case, you may want to contact your mechanic for these repairs as replacing the water pump impeller can get a little tricky on some model outboards.

Note:  Make sure that you stay well clear of the propeller, just in case someone puts the engine into gear.


  • Once you have run the engine for approximately 5 minutes, disconnect the fuel line if you have a fuel system with a quick disconnect type fuel line & keep running the engine until it runs out of fuel. This is a little more critical on 2 stroke carburetted engines.
    •  If a fuel/oil mixture is left in a carburettor for a period of time, the fuel will evaporate leaving the oil in the carburettor bowl, this will then dry out & gum up your carburettor. If this happens you will be up for a carburettor overhaul.
    • If you have a fuel injected engine or you have an engine that the fuel line can't be disconnected easily, it is best to put a fuel stabilizer into the fuel tank before you start to run the engine. This is only needed if the engine does not get run much.
    • Another preventive task to stop the fuel system from drying out & varnishing up is to keep the fuel system on the engine full of fuel. You can do this by squeezing the fuel primer bulb once a fortnight.
    • If at all possible, the best way to keep the fuel system in the engine fresh & clean is to run the engine (with the flushing adapter) for a few minutes every couple of weeks.


  • It is a good idea while the engine is running is to have the motor cowling off so that you can be visually inspecting the engine for fuel leaks, water leaks, loose bolts, corroded parts, loose wires ect.
    • After the engine has been turned off it is a good idea to put a little grease onto the cable ends & carburettor linkages.
    • Spray the engine down with an inhibitor like WD-40 or INOX to protect it from corrosion.
    • Replace the cowling & give the outside of the motor a good wash down with soapy water. Thoroughly rinse off with fresh water remembering to wash in & around the hydraulic trim & tilt system. Tilt motors are made of painted steel & are susceptible to corrosion.


  • If you boat is fitted with a battery isolator switch, turn it off before storing the boat. If not, remove one of the battery cables from the battery. This will help the life of the battery & to assure that nothing has drained it down during storage.


  • If a battery is left for a long period of time they will drain down even with nothing hooked to them, so it is a good idea to have small battery trickle charger hooked up to the battery to keep it charged during storage.


  • This may sound like a lot to do after each use but it is actually quite simple to do. In short summary, your routine will be, flush it, wash it, protect it & turn off the battery. If this sequence is followed after each use, your outboard motor will last many years.

 Regular checks


  • Fuel systems are the largest cause of outboard motor break downs. A few simple checks will significantly reduce a breakdown.
    • A water separating fuel filter is a must between the engine & the fuel tank, if your boat does not have one installed I would highly recommend contacting your mechanic or Dolphin Marine to have one installed. This filter will trap water before it gets to your engine. Water is a common problem in fuels today, between condensation build up in the tank & moisture being attracted to your fuel, over time this build up of moisture will stop your engine from running if you don't have a system in place to stop it.
    • If you do have water separating fuel filter in your boat, well done, but you are not completely safe unless it is maintained. This filter is designed to be checked regularly & replaced annually. Some filters have a glass bowl on the bottom with a drain valve; this is a great idea for a quick visual check to see if water is present. If it is, it can be drained out of the filter quite easily with the drain valve. Water is heavier than fuel, so it will always sink to the bottom.


  • Fuel Lines are another threat. There are a number of different manufactured fuel lines on the market today & some are just not holding up to the fuels of today. They are deteriorating from the inside which is not good at all for your fuel system. When this happens, small amounts of rubber hose are breaking off & travelling into the engine's fuel system causing blockages & once again a mechanical breakdown leaving you stranded.
    • Visually check your fuel lines, if they are cracked on the outside or if they are stiff then they definitely need replacing.
    • If your primer bulb is stiff or hard to squeeze, replace it.
    • Ask your mechanic or Dolphin Marine if your fuel lines are of good quality. Unless you have knowledge of the poor quality fuel lines & what they doing on the inside, it is sometimes hard to tell. Poor quality fuel lines will work for a short time but will then deteriorate within a few years.
    • Fuel connections - Fuel connectors have rubber orings, these are needed to seal the fuel from leaking out. Over time these orings will get hard & brittle, when this happens, either a fuel leak (which is quite easy to see) will occur, or they will create an air leak into the fuel system, causing the engine to starve of fuel. This condition is harder to find. Check your fuel connectors & replace them if needed.


For further inquiries as to how to look after your outboard motor or any problem that you may have contact Dolphin Marine, we will be happy to assist you.