OMC 5.0 305 wot lag and power surge

[nportwine]

Pulled the fuel pickup tube and anti siphon valve, going to replace the valve and line to the motor, and cleaned the fuel pickup in the tank.

 

[nportwine]

Boat ran a heck of alot better with another new spin on filter and the antisiphon valve and fuel line from the tank replaced. i had it up to 4600 rpm and towards the end of the day I could only get 4300 before it bogged. Should i just keep replacing the fuel filter? The tank didnt look that dirty at all but i did pull and clean the pickup. Could it be a fuel pump or are those more of a it works or doesnt type of part

 

[nportwine]

Also the temp gauge tends to stay over 160 but can’t tell if it’s really at 170 or 180 since the next number is 240. Does that temp sound okay?

 

[Bondo]

Should i just keep replacing the fuel filter?

Ayuh,..... 'n you Should be examnin' the Contents of the ones yer takin' off, for anything but clean fresh gasoline,....

 

[nportwine]

If I atleast drain the fuel filter and clean the carb with some cleaner to get rid of the carbon build up the boat will run near perfect for close to an hour, then the problem comes back, and i have trouble getting it to hold 4000 rpms even. Temp about 170-175. Have changed oil now, fuel filter multiple times, fuel inlet filter, the line from the tank to the spin on filter, anti siphon valve, and cleaned the pickup in the tank, The fuel filter usually has some black particles in it when drained, but the tank did not appear to be dirty when I examined it. would like try to something else before i use it today, probably going to run some seafoam spray through the Carb and change the fuel filter again

 

[Bondo]

Ayuh,..... What's the tank made of,..??

 

[nportwine]

Ayuh,..... What's the tank made of,..??

It is an aluminum tank

 

[Lou C]

You might want to CAREFULLY (turn off the batt switch first) remove the sending unit cover on the gas tank (careful with the small screws, get a new gasket while at it) and lift out the tank float etc. Shine a bright LED flashlight down to the bottom of the tank and see how it looks. If there is a lot of crud and water in there, have it professionally cleaned out. This way you start with a clean tank, new filter and clean carb. Otherwise you'll be chasing your tail. Gas should look like mine here....

 

[nportwine]

You might want to CAREFULLY (turn off the batt switch first) remove the sending unit cover on the gas tank (careful with the small screws, get a new gasket while at it) and lift out the tank float etc. Shine a bright LED flashlight down to the bottom of the tank and see how it looks. If there is a lot of crud and water in there, have it professionally cleaned out. This way you start with a clean tank, new filter and clean carb. Otherwise you'll be chasing your tail. Gas should look like mine here....

I pulled the sending unit and checked out the tank, it looked pretty darn clean, couldnt see much stuff on the bottom. I replaced the anti siphon valve and the fuel line going from the tank to the filter. When draining the filter after use, theres some black specs but it doenst seem to be enough to do all that much. When first going out, the boat will go up to 4500 rpm and run about 37mph. After awhile, i can only make it up to 4100, then slowly it becomes a struggle to hold 4000. So far ive replaced the spin on filter and the carb inlet filter as well as the anti siphon valve. Ive ran it with the gas cap off as well to check if its the tank vent, and it didnt seem to help at all. My feeling is that the pump is weak but I know mech pumps are fairly low pressure and not sure if that could actually be it. It seems like if it was a carb issue it would be constant and not get worse throughout the day, but I am going to order a kit in the near future anyways

 

[Redrig]

ignition coil breaking down after it gets too hot ?

I had an old ford that would have similar symptons and very had to diagnose since it only happened occasionally after getting hot ..... a new coil fixed it . Just a thought

 

[nportwine]

ignition coil breaking down after it gets too hot ?

I had an old ford that would have similar symptons and very had to diagnose since it only happened occasionally after getting hot ..... a new coil fixed it . Just a thought

May be something to think about, my grandpa put a pertonix kit on it when he owned it but I do not know if that included a new coil or not