Manual / instructions needed for Yamaha 8HP long shaft OB

ProDave

ProDave

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In advance of our new boat being delivered, I am seeking the owners / service manual for it's Yamaha 8HP long shaft outboard motor, with remote control and electric start.

I don't have any model numbers but here is a picture of the motor in the boat.

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In particular I want to be prepared for one of the first jobs when we get the boat, an oil change.
 
Gearbox oil is easy. Remove bottom and upper screws, drain oil and pump new oil in via the bottom screw until it appears at the top screw hole. If there is an oil filter use the local yamaha dealer for spares and the oil and they should advise you on the quantity's. Also check the fuel filter.
 
There is a manual online for this - I used to have it, will see if I can find a link. If memory serves, it’s actually the manual for a Mariner 8hp, which is identical OB.

Vic S is your man for OB manuals, hopefully he’ll be along soon. If not, PM him - he’s a mine of information.

Oil change straightforward though. There’s a screw half way down the OB leg - that drains oil, then fill till dipstick is showing correct level. Some of these have a small screw in oil filter too - check manual.
 
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Visit the official Yamaha website (www.yamaha-motor.com) and navigate to the Marine section. Look for the "Support" or "Owner's Resources" area, where you can often find downloadable manuals. You can search for the specific model or browse through the available manuals until you find the one that matches your outboard motor.
 
My understanding is there is engine oil in the engine in the head of the unit? That is what I am thinking about in the immediate term. It is vital to have the correct and good engine oil to run a 4 stroke.

Separate to that there is gearbox oil in the leg, that does not usually need changing as often, I am thinking apart from checking it has some oil, that can wait for the winter.

Am I on the right lines?
 
ProDave said:
In advance of our new boat being delivered, I am seeking the owners / service manual for it's Yamaha 8HP long shaft outboard motor, with remote control and electric start.

I don't have any model numbers but here is a picture of the motor in the boat.

In particular I want to be prepared for one of the first jobs when we get the boat, an oil change.
Click to expand...
You should be able to find the owners manual on Yamaha's website but you will need the engine ID details..
Owners Manuals - Yamaha Outboards

ITYWF that Mercury & Mariner engines are rebadged Tohatsus

Filling the gear case via the bottom hole is the standard method. It ensures all the air is displaced and is less messy than trying to fill at the same time as allowing air to escape using only the vent hole
Fit new gaskets to both screws.

If the old oil is not "clear and bright" it indicates water in the oil caused by bad seals.

Unless you know it has been changed recently fit a new water pump impeller.
 
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VicS said:
Owners Manuals - Yamaha Outboards

ITYWF that Mercury & Mariner engines are rebadged Tohatsus
Click to expand...

You are correct, but I found this that suggests that Tohatsu also made outboards for Yamaha:

“Sometime in early 90s or late 80s Mfgrs got together and funded a company in Japan to make all the small ob motors. The company created was named Marubeni. Marubeni supplied all the oem motors to Nissan, tohatsu, Mercury, Mariner, Yamaha, etc. The company eventually got absorbed by Nissan. You can go to either the tohatsu or the nissan sites to get a copy online of the manual for that motor. Either a nissan or tohatsu manual for a similar year 9.9 motor will help.”

Certainly the Mariner 9.9 manual was exactly correct for my Yam 9.9
 
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