97' Bayliner 4.3L Drops down to 1,500 rpm if going above 3,00 rpm HELP PLEASE

[97bayliner Capri SS]

Hello and thanks for any help. I would like to start by saying the boat was drained and stored inside for 4yrs. We changed all the fluids added gas and fired it up. It idled fairly well but would die if pushed above 1,200 rpm. I rebuilt the 2 barrel carb from top to bottom with new power valves etc. Set the float at 9/16" and float drop at 1-1/32". Idle mixture screw is out 1-1/4 turn. So know the 4.3l will run good at 3,000 rpm but if i try to go up it will just drop down like i pulled the throttle back. It drops down to about 1,400 rpm. I can immediatley give it throttle again and vome back up to 3,000 rpm.

Also, when i pull rpm back to about 1,500 rpm it will then just drop to idle at 500rpm. Like i put it in idle.
What should idle be set at?


97' Bayliner Capri SS with 4.3L v-6 and alpha 0ne. 2 barrel carb #807764
1) Carb has been rebuilt completely
2) New filters in fuel line and carb
3) new fluds all around

ANy help would be apprieciated..

 

[QBhoy]

I’d check the fuel tank pick up pipe for blocking. Especially if it worsens under load.

 

[Rick Stephens]

Sounds like a fuel problem. And is likely to be a fuel problem after parking it for a few years. Still possible, if not likely, that there is an ignition problem, but start at fuel.

We know it is carbed, so that makes it fairly simple list of things that will do this.

Fuel pump failed

Plugged fuel line or anti syphon valve.

Float set wrong

Missed a filter


First thing I would do is pull the fitting loose at the carburetor and stick into a clear container. Crank the motor and see if you get a good flow of fuel. Next step above that is attach a pressure gauge and see if you get the 6 or 7 pounds needed to supply your carb.

Don't be afraid to redo the carburetor rebuild. Lots and lots of times needs doing twice.

Rick

 

[Bondo]

Ayuh,...... Welcome Aboard,...... Hook a tank of clean fresh gasoline to the fuel pump to see if ya got a problem with the boat's fuel system, or the motor's fuel system,.....

 

[97bayliner Capri SS]

Thank you all for the answeres. i will try these and get back with you.