Logo
FULL SITE MENU

Carb problems on 2 barrel 4.3 v6

I

itmike50

New member
I just got this boat and it had been sitting for about a year with gas in it.
I drained the tank, replaced the fuel line with a fuel filter inline, cleaned the fuel pump filter, cleaned out the metal fuel line to the carb, cleaned out the carb screen from the fuel line(which was half full of crud), then pull the top half of the carb and found the float was mis-aligned, so I set it in there correct.
I took it out and and out of the hole it ran amazing, got right up and ran at full throttle. After the engine warmed up it began to die again.
I found out that the automatic choke electrical connection was broke and the choke was on. So i disconnected the choke and started it up again.
It ran fine again for a little while then at any throttle range other than idle, it would run up hard and then slowly die like it was not getting gas.
I checked the fuel filter and it was getting gas in it, but it wasnt that full, but you could see it pulling the fuel through.
I am not sure why it is dying like it is unless my float got stuck again, which I am checking tonight.

Any suggestions?
 
When you disconnected the choke, are you saying you turned the choke t-stat to a leaner position, ensuring the choke plate is remaining completely open...including under throttle conditions?
 
Fastatv said:
When you disconnected the choke, are you saying you turned the choke t-stat to a leaner position, ensuring the choke plate is remaining completely open...including under throttle conditions?
Click to expand...

No, I disconnected the spring plate because the electrical connection broke and the choke wasnt coming off.

I dont know what a anti-siphon valve is or where it would be.
 
its a spring loaded check valve at the tank. The first fitting you see with the barb on it.the ball tends to stick closed sometimes restricting flow
 
Bt Doctur said:
its a spring loaded check valve at the tank. The first fitting you see with the barb on it.the ball tends to stick closed sometimes restricting flow
Click to expand...

So off of my tank I have 3 outlets.
fuel filler
fuel vent
fuel delivery

I have a clear fuel filter on it so I can see it getting fuel. The filter was horizontal, so I think it might have been getting air and then fuel and then air again, causing the surge in running. I realigned the fuel filter to be horizontal last night and test running it today to see if that was the problem.

I have attached at picture of the before the filter, which line would have the check valve in it and how do you check to see if it is stuck?
 

Attachments

  • IMAG0602.jpg
    IMAG0602.jpg
    91.1 KB · Views: 368
You might also check your vent line from being plugged or fuel in a low spot. As you state, it's starts to act up after running a bit. If that vent line is plugged, you might be vapor locking the fuel system?
 
remove it and try and blow thru it from the tank side. replace with a barbed fitting FOR TESTING or use a remote tank
 
I am so new to this. I will look to see where the vent tube goes, not really sure where it ends up.

I will also blow some air through the check valve and see what that shows me.

I do have several extra tanks, so I could use one of those also to see if it takes care of the problem.
 
Update:
So I blew out the check valve and the breather tube. I changed my fuel filter to be mounted vertically instead of horizontally.
The boat ran much better, got up and ran hard.

The next problem I am looking at is when towing someone on a tube, it was not getting out of the hole and had a hard time getting up to plane.

The engine was laboring hard getting past 3K rpm. Not sure why, but need to figure that out next.
I think I need to change my prop, no I dont know what the pitch or anything of the existing prop is.

Anyway, thanks for the help on my last problem, now on to the next one!!!
 
Back
Top