5.7 Mercruiser Unhooked wire near choke

[RHUBBARD422]

Just recently purchased first boat. A 1992 Rinker Captiva 206. The boat runs strong 99.9% of the time but seems to have an issue after the first initial start up. The boat will fire up pretty easily and will idle smoothly for 30 to 60 seconds. Once 30-60 seconds go by it wants to die and will not run unless i give it a bit of throttle. It takes a good 8-10 minutes of that before it will idle normally. That made me think that maybe it just takes a bit to warm up. However, sometimes (not all the time) it acts like it wants to die after running an average speed then backing down to idle speed in a no wake zone so i have to bump up the throttle just a hair or sometimes it will idle through a no wake zone with no issue. When the boat is not idling it runs perfectly. It is strong and gets on plane very quickly. Its just kind of annoying pulling up to a dock and having to pump the gas to keep it running. (simetimes)

I have gathered some possible issues from other forums and friends with boats and they said it could be a choke issue or the fuel/air mixture screws could be set too rich. I removed the plastic cover over the spark resistor and noticed an unhooked wire. (picture attached) I'm wondering if any of you could recognize what this might go to? Possibly the electric choke? Thanks for taking the time to read this. Hopefully i didn't break any forum rules by asking dumb questions or asking a question in the wrong section. I just joined today so bear with me. Thanks!

 

[alldodge]

Unable to tell what color the wire is, if its black then its a ground. Your initial problem could be a choke issue and may just need to be adjusted. Choke should be closed with a 1/8 gap opening when cold. If choke opens to soon this will cause the need to give it throttle to keep it running.

Once warmed up the choke should be fully open. May just need the carb cleaned and rebuilt. From your pic it appears you have a Q-jet so there is a filter kit 1397-8767Q which may be part of the issue if it has not been replaced. When was the last time the filters were replaced

http://www.mercruiserparts.com/Show_...2D+4+BARREL%29

 

[RHUBBARD422]

Should there be an 1/8" gap when the engine is cold and shut down or when it is running cold? The guy i bought it off had a new engine installed and only put about 10 hours on it. I don't know if that included a carb rebuild or filter replacement. I will pull the cover off and check for the color of that wire tonight. I am thinking it is the same color as the wire to the left of the hose clamp in the middle of the picture. I will let you know for sure. Thanks for the quick response.

 

[alldodge]

Should there be an 1/8" gap when the engine is cold and shut down or when it is running cold?

The gap should be like for the first start in the morning when everything is cold.

 

[Bt Doctur]

that QJet uses a bimetal element not an electric element for the choke

 

[thumpar]

It sounds like a combo of choke not adjusted and carb needing rebuilt or adjusted.

 

[RHUBBARD422]

Thanks for the info everyone. Since the choke works off a bi-metal element i guess that eliminates one thing the mystery wire could go to.

 

[RHUBBARD422]

No Title

The wire appears to be orange with a blue or greenish stripe down the side. Any ideas? Thanks again for the help.

 

[alldodge]

Its tan/blue and all of those color wires go to the warning horn system. Oil pressure switch, outdrive lobe bottle and thermostat temp switch. So with a ring terminal and being near the thermostat it would go to the thermostat switch if you have one. This is another sensor mounted on the thermostat housing other then the temp sensor which goes to your gauge and has a tan wire (no stripe) going to it (may also have a black wire if uses two terminal plug)