1985 Mercury 115 6 cylinder 2 stroke fuel screen

luvnarose

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I have a 1985 Mercury 115hp 6 cylinder 2 stroke motor. I have had a problem with the motor wanting to die under load or when it does try to run it will not go much more than idle speed. I was told that it is probably the fuel screen it clogged. I looked at the motor but not sure where the screen is. Can anyone help me so that I can try to fix this issue. Thanks.
 

Chris1956

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According to the parts list, you either have the old style fuel pump or the new style fuel pump. The new style fuel pump will have an inline plastic fuel filter. You should see it.

The old style fuel pump will have a screen under a black plastic cup. Trace the fuel line into the engine and look for an upside down cup, an inch or so inside the motor. It will have a stainless steel Phillips screw in the center. Remove the screw and under it will be an oring and a screen.

You also have fuel screens under the brass fittings that go into the carb covers. They hardly ever clog.
 

racerone

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Open the low speed mixture screws 1/8th turn at a time.-----test run after each adjustment.------You may find that the bogging will go away.
 

luvnarose

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Open the low speed mixture screws 1/8th turn at a time.-----test run after each adjustment.------You may find that the bogging will go away.

I found the screen and cleaned it and it ran great. I tried putting around a little and then try to give it more gas and it would bog down for about 5 minutes then take off again. Did it everytime I tried doing that. I have the one with the cup that the screen is in.

Where are the low speed mixture screws?
 

luvnarose

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Open the low speed mixture screws 1/8th turn at a time.-----test run after each adjustment.------You may find that the bogging will go away.

Well I messed with the low speed mixture screws but it was with muffs in my yard and it doesn't bog down that way only when it is under load on the lake
 

racerone

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Oh well.----Why not test it in the lake then.----You may not be aware of this simple procedure to get rid of bogging on these inline engines.---- ---TEST RUN IN THE LAKE----Is what I meant..------You can not fine tune one of these engines running on a hose !!!!
 
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