Idles for about a minute then stalls, then have to reprime

[Friscoboater]

Little history,

Replaced a rotten transom this winter and did a 228 to 260 repower. Ran the engine out of the boat and it ran perfect. It would idle and everything.

Now it is in the boat and runs perfect while you have it reving, and will idle for a minute and then will quit. I then have to spray ether in teh carb to get teh motor running again. Again it will run perfect if i keep it over idle, but when you go back to idle it is fine for about 60 seconds.

Here is what I have
Rebuilt Q-Jet
New Fuel pump
New Merc 260

The only difference is the gas. The gas in the boat is from October. I am thinking I might gave it adjusted wrong, but I do not know where to start.

 

[Don S]

Re: Idles for about a minute then stalls, then have to reprime

You have either a clog or an air leak, oar both in the fuel system from the tank to the fuel pump.
Just hook up a remote fuel tank (an outboard tank works) just to make sure it keeps running. If it does, then you have fuel system problems. There are tests for the boats fuel system in the Adults only sticky, but if you can't keep it running, it won't be much help.

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

Should I be able to see fuel down the little overflow tube? It looks moist, but I seem to remember fuel being in there. I read that sticky and I am going to check the pressure, but everything was fine in October when i yanked the engine. That is why I thought it might be a little bad gas.

BTW it ran great on the tank outside the boat.

 

[Don S]

Re: Idles for about a minute then stalls, then have to reprime

If you have fuel in the clear hose between the fuel pump and the carb, then you have a bad fuel pump. It's just that simple. That is the only thing that hose is for, to redirect fuel from a faulty fuel pump to the carb.

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

No not that little sight glass. The little tube on top of the carb that lets you see in the fuel bowl.

the little sight glass is clean.

 

[Don S]

Re: Idles for about a minute then stalls, then have to reprime

I have no idea what you are referring to.
WHat engine, what year, got a picture????

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

81 260 with a Q-jet. On top of the q jet is a tube that allows excess fuel to be dumped into the carb. You can see right down in the fuel bowl.

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

Ok, I just did some testing. Fuel pump pump like mad and when you hit the gas the carb shoots fuel down the throat. Could I have this carb running too lean on the idle mixture?

 

[Don S]

Re: Idles for about a minute then stalls, then have to reprime

The idle circuit has nothing to do with the accelerator pump circuit or the fuel pumps ability to pump.
You could have carb problem, or ignition/timing problems, or both.
Have you ever had water in the carb or fuel filter/water seperator? have you checked?

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

I will post a video in a little while and you can see how it dies.

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

Here is the video. In the middle it does it twice.

http://www.youtube.com/watch?v=SIEvB1iy780

 

[Don S]

Re: Idles for about a minute then stalls, then have to reprime

It sure sounds like a carb problem, I'm going to listen to it again.
BUT, in the meantime Do NOT put that transducer that close to the outdrive, or you will be getting cavitation burn on the prop.

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

Will do. Thanks for the advise! You might want to wait until it finishes processing at YouTube and watch it in HD. It just sounds like it flat runs out of gas, after I listened to it on video.

 

[Don S]

Re: Idles for about a minute then stalls, then have to reprime

I just listened to it die about a dozen times. Still not sure. Could be just leaning out till it dies. Don't see any black smoke like it's loading up.
Try backing both idle mixture screws out 1/4 turn and see if it idles better.
If I was there I would put an educated hand over the choke opening and see if slightly less air would help. But have no idea how to explain that one.

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

I understand the hand thing. I usually use a shop towel. It was getting late so i had to stop farting around, or risk pissing off the neighbors.

Thanks for the help Don.

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

I figured it out. I took all the lines off and found a blockage of fiberglass from the restoration. Everything runs great now.

 

[betayv]

Re: Idles for about a minute then stalls, then have to reprime

good frisco so when are you going in the water?

 

[Friscoboater]

Re: Idles for about a minute then stalls, then have to reprime

I think Sunday. We have alot of plans this Saturday and it is raining today.