loss of power

[joshandsteve]

I have a 1994 Four Winns with an omc 3.0 gs. The boat is new to me and the first time out it ran great for about 45 min. After that it started losing power after any more than 60% throttle and back fires slightly through the carb. Since then I've changed the oil, the plugs, cap, rotor, fuel pump, and a new carb. and still have the same problem. Any advise??

 

[Reel Poor]

Re: loss of power

Have you changed the fuel filter?<br /><br />Also check the antisiphon valve at the fuel tank. Its the fitting on the tank that you engine feed hose is attached to. There is a ball a spring in it that can restrict fuel flow.

 

[Bob_VT]

Re: loss of power

How's the coil? They act up when they are going and get hot. <br /><br />Bob

 

[joshandsteve]

Re: loss of power

I have changed the filters and put in a new coil and new plug wires......no change?? Any more advise is gladly recieved. I also checked the anti-syphon valve.

 

[jeff13601]

Re: loss of power

Did you get a new carb or a used one new to you? Also do you know how old the gas is that is in it.

 

[joshandsteve]

Re: loss of power

The carb is brand new from National Performance (holley marine carb) when I got the boat there was maybe a couple of gallons of gas in it and I don't know how long it sat but when I got it I put a full tank of new gas in it.

 

[joshandsteve]

Re: loss of power

Could this be a timing issue or something major, (i.e. blown gaskets, or craked engine?

 

[jeff13601]

Re: loss of power

I know it sounds funny but it allmost seems like a carb. Did the old one work and do you still have it?

 

[Reel Poor]

Re: loss of power

Check the vent for the gas tank it could be plugged. When it starts acting up remove the gas cap to see if that clears the problem. You may hear suction when you loosen the cap if this is the problem.

 

[Bondo]

Re: loss of power

It's No Doubt a Fuel Delivery Issue.........<br /><br />You've got to figure out,... Why.......