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2008 30hp mercury bogging down under load

M

motiondave

Contributing Member
Hello good people, hopefully someone can advise and or help.
I have a 2008, 30 hp mercury 2 stroke, the lighter 53kg motor. 0N103053
it bogs down under load
Overall, the motor is in very good condition, but looks to have, at some stage, had the power head off and the cylinder head off.
Making us think it may have been apart form some reason.
There is 3 manuals for it and I dont really want to spend over $200 for all from a dealer here in Australia for them.
just about everything else is checked, replaced , cleaned. Compression is fine, no leaks, fuel system perfect.
the only things we have left to consider is.

the timing,
as we are not sure what its supposed to be and there is no markings on the flywheel to line up to the marks on the motor block.
ive read the lever off the throttle has two adjustable screw type lever thingys, sorry I dont know exactly, that move the timing, however, Ive found out they are supposed to be a distance, centre to centre, but im not sure the actual length, can any advise please?

the carburettor , we tested a few things, under load, including winding the air fuel screw almost shut to see if the jets had been drilled out. Nope, still bogs, but not completely ruled out if jets have been drilled out.

Unless the actual motor is assembled incorrectly somehow, we are just about out of ideas

does anyone have any suggestions please?
Kindest Regards, David Lane.
 
edit, I found out there is a coil pack under the flywheel consisting of a charge coil, for the battery and an exicter coil for the spark coil. I will replace those next.
But..if anyone else has any ideas, please let me know.
 
Pretty sure it is a Tohatsu rebadged as a Merc....those Mukini carbs are picky about float level and being clean. You will need to match up carb parts off Tohatsu/Yamaha sites as Merc posts parts NLA for this motor
 
thanks fastjeff and faztbullet

I had a good phone call with mercury mechanic today.
Yes its a tohatsu under all that.

we established the timing is right, we had though that the coils under the flywheel are stuffed, probably not.
He told me of two things, Ive ordered an inline spark tester as NO ONE in Sydney Australia has one on the shelf. so thats another 1-2 weeks wait.

first thing, test the spark as the wires coming out from under the flywheel might be crimped and shorting out.

second, the carby, although its 100% clean, Im ordering a kit for it just in case there is something missing and or the jets may have been drilled out.
this motor has done stuff all work in 12 years.
 
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