Don or Bondo, 4.3 wont run right???

[sledstew]

I wrote earlier stating my boat motor was recently rebuilt (1988 Lund with 4.3 liter/ cobra outdrive) and Im having trouble with it running at low rpm and at high rpm in the water. If the boat is out of the water with the muffs on it runs fine. Here is what Ive done to narrow it down, rebuilt the Carb, checked fuel lines, replaced fuel filter/seperator,replaced water pump impeller.When the boat is initially put in the water it runs good for about 5 minutes then it dies out.After sitting a bit it will start back up but will not idle I have to keep it reved up above 1500 rpm in nuetral or it will die.While in the water The boat will run in nuetral from 1500 to 3500 rpm with my hydraulic troll on all day but the minute I put it in gear it only runs a short time and dies. After the boat dies in the water I have to give it gas in nuetral in order for it to start.It acts like its flooding but having a hard time believing it. Also I was wondering if points and condenser would do something of this nature, or maybe the coil?

 

[jeff13601]

Re: Don or Bondo, 4.3 wont run right???

It costs 10 dollars for points, cond and rotor. For that little bit do it as it should be done anyways. Then you can rule that out. Do the plugs and cap while you are doing it.

 

[sledstew]

Re: Don or Bondo, 4.3 wont run right???

I replaced the rotor condenser and points and its still acting the same.

 

[jeff13601]

Re: Don or Bondo, 4.3 wont run right???

Did you set the points with a dwellmeter or did you gap them?

 

[jeff13601]

Re: Don or Bondo, 4.3 wont run right???

Im not sure whether or not it is true but I was told that when coils start to go they can get hot and malfunction. You probably should check the pickup screen in the tank and the antisyphone valve at the top elbow out of your tank

 

[sledstew]

Re: Don or Bondo, 4.3 wont run right???

Jeff, I set the dwell at .018 and I checked all the fuel lines and the antisyphone valve. It is running right now with the muffs on it, The motor is warm and when I go to 1000 rpms it will not idle it slowly starts to drop rpms and dies.

 

[sledstew]

Re: Don or Bondo, 4.3 wont run right???

Is there any way to check the coil to see if its good, multimeter or some other way?

 

[jeff13601]

Re: Don or Bondo, 4.3 wont run right???

Look at your manual or the side of your engine but isnt that the point gap and the dwell should be about 30. I was told once how to check a coil but I can not remember. Someone else with more exp may jump in on this one. When it dies are you looking to see if you are still getting fuel?

 

[sledstew]

Re: Don or Bondo, 4.3 wont run right???

Jeff , How do you check if its still getting fuel when it kills on me? The best way to start it up after it dies is to put it in nuetral with the throttle wide open then it seems to fire right up. My book says .018 for the gap.

 

[sledstew]

Re: Don or Bondo, 4.3 wont run right???

Also would old gas be a cause of all this, the gas smells good but it has been sitting for 2 years, prior to the boat sitting seafoam was added to the tank.

 

[jeff13601]

Re: Don or Bondo, 4.3 wont run right???

Let it idle and go back and take off arrester and look into carb. You need to set the points with a dwell meter. You could have a fuel pump problem. need to run good luck

 

[sledstew]

Re: Don or Bondo, 4.3 wont run right???

Another question ,does a boat require more fuel in gear than out of gear in nuetral? Im going to check the pressure on my fuel pump and see if thats it, If I remember right I believe it should have 7lbs of pressure.

 

[sledstew]

Re: Don or Bondo, 4.3 wont run right???

 

[Bondo]

Re: Don or Bondo, 4.3 wont run right???

Originally posted by sledstew:<br /> Another question ,does a boat require more fuel in gear than out of gear in nuetral? Im going to check the pressure on my fuel pump and see if thats it, If I remember right I believe it should have 7lbs of pressure.

7psi would be the Upper Limits,........<br /><br />I usually shoot for 4 to 6 psi,........<br />And,... It Shouldn't Drop at WOT........