'87 80hp Mercury won't idle

[CoJeeper]

New to this forum. I have a 1987 80hp Mercury, that runs great wide open, but only idles for a few minutes under power before it dies. If you pump the primer bulb when it's idling, it picks back up and purrs right along for a few minutes then starts to die again. As long as you pump the primer bulb every few minutes it will idle right along. One thing to note this motor was out of the water for a few years while my boat transom was being rebuilt. Any ideas on what might be causing my idle problem. One other note, it does have a fuel leak at the fuel connector that I'm working to get fixed, may need a new fuel hose connector. Thanks in advance for everyone's insight and advice.

 

[Chris1956]

A fuel leak can also let in air, causing loss of fuel for idling. High speed pumps more fuel and may mask it.

Fix the leak and retest. If that doesn't fix it, rebuild fuel pump.

 

[CoJeeper]

A fuel leak can also let in air, causing loss of fuel for idling. High speed pumps more fuel and may mask it.

Fix the leak and retest. If that doesn't fix it, rebuild fuel pump.

Thanks, I figure the leak is having an impact. I also intend to look at the fuel pump and fuel filter. Thanks again.

 

[CoJeeper]

A fuel leak can also let in air, causing loss of fuel for idling. High speed pumps more fuel and may mask it.

Fix the leak and retest. If that doesn't fix it, rebuild fuel pump.

Chris1956 any idea where I could find the female and male connectors for a '87 Mercury 80hp? I've been searching the internet without a lot of luck for the OEM parts, no longer available. Will keep looking, found some parts not sure they'll fit. Thanks.

 

[Chris1956]

I have never looked for those. You could permanently connect the fuel line to the motor using a brass double hose barb in 5/16" ID from a hardware store, plus a couple of hose clamps or wire ties.

I also would expect the fittings to be available aftermarket, but not sure where..

 

[CoJeeper]

I have never looked for those. You could permanently connect the fuel line to the motor using a brass double hose barb in 5/16" ID from a hardware store, plus a couple of hose clamps or wire ties.

I also would expect the fittings to be available aftermarket, but not sure where..

Yeah, I've been thinking about doing that, since my tank is built in. Doesn't make sense to use a connector made for a portable tank, just one more spot for a leak or air getting into the system. I have found some parts however I'm not sure they would fit even though they look the same, plus the double barbed hose fitting is a lot cheaper. Thanks for the help and advice.