4.3 engine stalling

[blhines]

I have a 1997 maxum sr1900 4.3l 2bbl carburetor. Went out on the lake on the 4th and it ran like a charm all day. Went back out this past Saturday it would run awesome for about a minute then act like it was running out of gas . So took it home changed carburetor still did the same thing . Changed the fuel pump still did the same thing cleand all fuel lines brand new fuel filter new plugs . Still doing same thing with new carb and rebuilt carb . Any help would be greatly appreciated I'm at the end of my rope with figuring it out and what else to check

[mmwjr]

Does it start right back up or do you need to wait some time before it will restart? Next time it happens remove the fuel cap to see if the issue goes away. May be a clogged vent.

[blhines]

Have to wait just a little bit then fires back up

[mmwjr]

Originally Posted by blhines

Have to wait just a little bit then fires back up

Try removing the fill cap next time to see if it fires right up.

[blhines]

Ok removed the gas cap ots still doing the same thing. It will fire back up and go another minute before cutting off again. It don't just cut off it will spit and sputter for a bit and try to run then shuts off. If I try to give it gad it shuts right off.

[donald]

Bad Coil
Don

[mmwjr]

I’m thinking it’s electrical and not fuel such as a bad ignition coil or ignition sensor in the distributor.

[blhines]

Ok update changed coil rebuilt carb and have new carb both doing same thing . I hooked water muffs at the house this past Saturday night ran fine . Next morning started it right up ran fine took it to the lake as soon as it was in the water wouldn't fire so gave it some gas finally fired up went to a cove around the corner from dock sit for a bit wouldn't crank carb over flowing when trying to crank unhooked the fuel pump cranked up and ran fine until all gas was out of bowl. But 2 carburetors doing the same thing is odd so I'm going to change fuel pump. I'm changing to fuel injection over the winter

[2004_3300_SCR]

I bet your new fuel pump will fix the problem.

I had a Merc electric fuel pump that was over pressuring the float and flooding the carb just like you have. Re-built the carb (twice, thinking I did something wrong the first time), still same problem. Measured pressure and found the pump was putting out over 40PSI. Added a fuel pressure regulator between the filter and carb, and dialed down the pressure. Worked for a short while, but then the pump completely died, no output. For some reason these pumps must over-pressure when they are about to die.

[mmwjr]

Not sure if you are mixing terminology. Not cranking meaning the engine isn’t turning. Not starting meaning it’s cranking but not firing.

Which are you experiencing? Two very different issues and causes.

[blhines]

It's the carb or fuel pump. Sometimes it's not getting gas and Sometimes the carb floods out

[mmwjr]

Originally Posted by blhines

It's the carb or fuel pump. Sometimes it's not getting gas and Sometimes the carb floods out

I’m pretty sure you have an electric fuel pump, sounds like it’s not regulating properly. Could be the internal regulator. An external regulator would help keep the pressure from getting to high but there’s nothing you can do when it drops to low. As suggested it may be time to replace it.

[blhines]

Yep Doing that this weekend and putting regulator on it

[mmwjr]

Originally Posted by blhines

Yep Doing that this weekend and putting regulator on it

Fuel pressure for a carburetor should be 5-7 psi. Not sure if an external regulator will fight against the pumps internal one. I would just replace the pump only to see if that works.

[Ajaasen]

Mine was doing this a couple weeks back and it turned out to be the circuit breaker wiring shorting out.