Rough idle

[BrocheN]

Hey guys,

So I'm getting my 1996 reinell 184brxl ready for a camping trip this weekend. It has a 4.3gs Volvo penta sx motor. I put the ear muffs on and started the boat. It started right up but with an extremly rough idle. I shut it off and started it up again with the same result. I then gave it a little gas and it revd up flawlessly. I then put the throttle back to neutral and it ran perfectly. I tried starting it up again and it ran fine. One hour later I tried starting the boat again and the rough idle is back. What is the problem here?

 

[Don S]

Re: Rough idle

Did you give it any throttle when you first start it? It's not EFI, you have to give it some throttle or it will idle rough because the choke is on.

 

[BrocheN]

Re: Rough idle

Yes I always give it a good 3 throttle pumps on a cold start.

 

[BrocheN]

Re: Rough idle

any other ideas?

 

[SSSuper83]

Re: Rough idle

Three throttle pumps is fine BEFORE you start the engine when it is cold. But you have to at least hit the throttle once as the engine warms up, at least once more as the engine reaches the normal temperature. The choke will stay on otherwise and cause a rough idle. You do not have to bring it up above 1000 rpms if you have a tach, just bring it off idle. That will help.

 

[BrocheN]

Re: Rough idle

Three throttle pumps is fine BEFORE you start the engine when it is cold. But you have to at least hit the throttle once as the engine warms up, at least once more as the engine reaches the normal temperature. The choke will stay on otherwise and cause a rough idle. You do not have to bring it up above 1000 rpms if you have a tach, just bring it off idle. That will help.

It has never done this before, though. It just happened for the first time yesterday. I would assume that the boat would have always done this if it were normal with the choke. I am welcome to more ideas.

 

[ryanr623]

Re: Rough idle

Is it vibration, and running well? Or just running roughly?

 

[OldNBold51]

Re: Rough idle

It has never done this before, though. It just happened for the first time yesterday. I would assume that the boat would have always done this if it were normal with the choke. I am welcome to more ideas.

The carburetor choke is a mechanical device. Mechanical devices can and do go bad. Either check it or not, it's your choice.