9.9hp 4 stroke Yamaha outboard Service/overhaul

Rum_Pirate

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NOW - The engine has not been used for 5+ years and has maybe 50 hours total use.

So have ordered a carburettor repair kit, gaskets etc.

The spark plug replacement is simple.
The engine oil replacement is simple.
The oil in the engine foot replacement is simple.
Replacing the throttle and gear cables which have corroded.
Will replace the fuel filter .
Will replace the water impeller.


What else would you recommend doing?
 
NOW - The engine has not been used for 5+ years and has maybe 50 hours total use.
So have ordered a carburettor repair kit, gaskets etc.
The spark plug replacement is simple. The engine oil replacement is simple.
The oil in the engine foot replacement is simple. Replacing the throttle and gear cables which have corroded.
Will replace the fuel filter .Will replace the water impeller.

What else would you recommend doing?
All the items ( mostly inspections ) on the maintenance schedule in the owners manual.
.
 
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anodes?
plug out and look at the bore (s) if they do not appear spotless I would be tempted to add 50 ml of oil to the cylinder with plug hole facing up and turn it over very slowly by hand 3 or 4 times then turn it over and drain it out for 10 min or so. That will hopefully scrape off and drain any crud before it can do harm.

Do this whilst ALL of your other oils are drained out. Refill as normal once back upright.

Probably over kill but if you want to be sure whilst doing the other stuff it wont harm.
 
Rubber fuel lines may be worth inspection and wiggling to make sure they have not broken down.

Last week I was giving my small outboard a basic service and run test. She ran ok but there was a strong smell of petrol. On inspection, there was a split in the hose where those spring clamps hold it to the carb which is hidden from view.

I did a web search which suggested that fuel lines are renewed every three to five years. I then went to my local car accessory shop and bought 2 feet of the fuel line for £5.80. I have decided to renew the fuel lines on my other two outboards.
 
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