Merc 80 bogs down intermittantly

[Imag8r]

Hello all,<br />I could use some advice please. My 80 HP Merc, 1987 ser# 0B145378, runs fine when cruising then bog down to a max of 2500 rpm for a while then suddenly back up to speed. It mostly bogs down now. I have replaced fuel line and filter. Plugs are clean and uniform with good compression (97, 105, 107). Carbs were overhauled by the dealer 2 years ago and look clean. Any Suggestions???? Thanks

 

[Barnacle_Bill]

Re: Merc 80 bogs down intermittantly

Did you replace the bulb too? They are the first to go. How about your fuel pump? When is the last time you replaced the diaphram?

 

[Imag8r]

Re: Merc 80 bogs down intermittantly

Thanks Bill,<br /><br />I replaced the bulb along with the gas line all the way thru the filter. I have the vent open from the tank so I get good fuel flow when I squeeze the bulb when the line is detached from the fuel pump. I had the fuel pump overhauled along with the carbs, but I will relpace the diaphram and see if that helps. Could it possibly be electrical? It just feels like it is a fuel problem if that make sense.

 

[Imag8r]

Re: Merc 80 bogs down intermittantly

Thanks Bill,<br /><br />I replaced the bulb along with the gas line all the way thru the filter. I have the vent open from the tank so I get good fuel flow when I squeeze the bulb when the line is detached from the fuel pump. I had the fuel pump overhauled along with the carbs, but I will relpace the diaphram and see if that helps. Could it possibly be electrical? It just feels like it is a fuel problem if that make sense.