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Tohatsu 30hp 2 Stroke Boggs down on acceleration

A

alleycat

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2006 M30A4 2 stroke.
Can anyone tell me the factory mixture ,number of turns, setting of the only main screw as i did not count the number of turns out from slightly seated when I overhauled the carby.Thanks
 
There is no "main screw". There is no "factory" setting for the pilot screw. About 1-1/2 to 2 turns out from lightly seated is a good start for the pilot screw. Then you must adjust on each installation. Also verify link and sync (timing) to make sure you have the correct spark advance. Did it work properly before? Is the prop pitch correct? Is the jack height correct?
 
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I checked the timing as per the overhaul manual,everything is within spec.The prop is original, the jack height is also the same as it has been since 2006.Coil has been checked,new fuel pump, new fuel, new plugs.
 
Assuming it once did work well, what has changed? What do the plugs look like? Does it start well? Is the float height correct?
 
Nothing has changed.The plugs are new,slightly sooty but not oily,comp 150 psi on both cylinders and starts well.Maybe the mixture screw is not out enough and it is too lean on acceleration, so I will take it out to 2 1/2 turns and try it on the water
 
done some electrical testing and found that the ignition coil is out of spec.
PRIMARY COIL .2 TO .3 OHMS MY COIL .2 TO .3 OHMS
SECONDARY COIL 4.1 TO 6.1 K OHMS MY COIL 0
With that faulty secondary, would that be giving the trouble on acceleration, is ok at idle.
 
You must use a good analog ohm meter to check these. Not digital. The output side should be nearly infinite to ground. If it were zero (shorted to ground), you would get no spark at all.
 
One of the biggest issue we have is set up fuel over winter. Almost all new carbs have a tiny idle jet tube and ethanol gas sets up in jet sets . If you crank engine with air silencer off , put your hand over front of carbs . If motor picks up , more than likely jet tubes
 
Finally found the problem.Replaced the spark plugs after testing the original ones out of the engine as they seemed OK. It appears they were breaking down under compression pressure.So thanks to all you fellows that had input into my problem.Regards Brian
 
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