Is This Normal? For 87 Mercury

H

heather1

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I HAVE 60 HP MERCURY, 1987 3-CYL. SER. # OB247899. Runs great in drive, but under load bogs down. Replaced fuel line , and connectors, and have had carbs replaced. But, primer will not stay hard, and gas is dripping slightly at slot screw? under carbs. is this normal? if not what do I do. Am I losing gas pressure.
 
JB

JB

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Re: Is This Normal? For 87 Mercury

If it is dripping gas you have a carb needle or float malfunctioning. Debris in the fuel can cause that.
 
mthieme

mthieme

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Re: Is This Normal? For 87 Mercury

Two of your symptoms would steer me towards throwing a fuel pump kit in.
Cheap and easy.
 
H

heather1

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Aug 8, 2008
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Re: Is This Normal? For 87 Mercury

Thanks guys for responding, I had checked the fuel pump and all of its guts, everything looked fine ,but what do I know, I'll get another one. Also J.B. how do I check the needle deal. and if there is debris inside? thanks in advance.
 
JB

JB

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Re: Is This Normal? For 87 Mercury

First, Heather, get a factory Service Manual. It is a really bad idea to work on an outboard without one.

You will need to dismantle the carb. While you do that you should clean it and give it new gaskets, needle valve and seat. Any debris in the bowl will be obvious.
 
achris

achris

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Re: Is This Normal? For 87 Mercury

Those particular engine are quite picky about new plugs. I've 'fixed' quite a few with weird problems by just putting new plugs in. Easy to do, cheap and could just be the problem you're chasing........

Primer not staying hard is normal. It only gets hard because you are pushing fuel against closed needles. Once the engine starts to draw fuel from the tank, then the pressure in the line drops to just below ambient, but no more than 2" of mercury (the metal, not the engine:D).......

Chris...........
 
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