Mercury 150 outboard 2 stroke maintenence

[A_champion]

I have a mercury 150hp outboard motor(2 stroke) and I want to clean out the carb and replace the spark plugs. So i need to know how u pull the cover off the top of the engine and If there is any other little thing to lube or check on this motor please let me know. Maybe if u have the torque specs on the plugs post that up too. thanks

[gw204]

If you have the owners manual, all of that stuff is covered in there. If you don't have it, you should be able to order one from your local dealer or through Merc's website. I highly recommend getting a copy.

Spark plug torque should be 20 ft/lbs.

[jeremiah2360]

You probably should de-carb too. I do this with my 1995 Merc 200 carbed outboard. I use a remote tank with 1 gallon gas and 1 can of SeaFoam and warm the motor up with this mixture. While the engine is still hot I tilt it up all the way and remove the spark plugs. Don`t force them with the motor hot,before you start you may want to loosen the plugs and re-tighten to make sure they are not over-tightened to begin with.

I then bring each piston up all the way to top dead center and spray some Mercury Power Tune in them,ten minute soak each,with a couple of squirts in the others for good measure. I use a ratchet and 15/16 socket(could be another size,going by memory) to turn the motor with the nut in the middle of the flywheel. Turn the motor in the direction it runs ,clockwise I believe,just observe which way it`s spinning with the cover off while it`s warming up.

After each piston has had it`s soak put the spark plugs back and fire it up. After it clears then put in the new plugs.

This is a combo method I adopted of Dunks de-carb(do a search you`ll find it) and what my mechanic suggested. My mechanic said to bring each cylinder to TDC otherwise the Power Tune just goes out the ports,made sense to me. Good luck!

[Brewhedd]

Not sure what you mean by the cover on top of the engine? I have a Merc 150 and they are good motors, refined over the years. I have used a can of Valvtec decarb twice a year for 4 years and this method works well and is very easy. Also check the small rubber lines running from the fuel enrichment valve to the carbs, they crack after a few years.

[jeremiah2360]

By cover I mean the cowling you take off to access the engine.

[strikerthree]

I run the mercury quick kleen 2x a season keeps the carbs nice and clean using the pennzoil semi synthetic oil also helps