1990 4.3 liter dies after about 30-45 minutes

[mgeorge15]

I have a 1990 celebrity with the 4.3 liter mercruiser motor in it and after about 30-45 minuts it will die over about 2000 rpm, it will start right back up and you have to keep it at low rpms for it not to die. I had this problem before and then the boat wouldnt even start up and i replaced the pickup in the distributor about a year ago. Are these known for going out often or do I have another problem?

 

[Don S]

Re: 1990 4.3 liter dies after about 30-45 minutes

So, is this a Mercruiser, or a Volvo?<br />Could be the fuel tank vent is plugged up.

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

sorry its mercruiser thought i put that in there, how do you check the vent?

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

would the fuel line going from the back of the carb down to the fuel pump being clogged cause this, because it was completely clogged

 

[vipzach]

Re: 1990 4.3 liter dies after about 30-45 minutes

Originally posted by mical:<br /> would the fuel line going from the back of the carb down to the fuel pump being clogged cause this, because it was completely clogged

you bet it would! now you should check your tank and change the filters, if you don't have a fuel/water seperator.......get one1

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

check what on the tank the vent?? where is that, ive already changed the filter on the pump, is there one in the tank? where do you put a fuel/water seperator at?

 

[vipzach]

Re: 1990 4.3 liter dies after about 30-45 minutes

You need to find out where the crap is coming from. There is a 90 degree fitting on the top of your tank, that is pickup tube. You can remove the fitting and look down in your tank, when it is almost empty, to see if there is junk in the bottom. No, there is not a filter on the tank itself, but there is supposed to be a screen on your pickup tube. There generally is one on the pump and one in the carb. A fuel/water seperator would go in line, before the fuel pump. I personally would recommend one for every boat that doesn't have one. They are pretty cheap, do a good job, and are easy to install.

 

[Chris1956]

Re: 1990 4.3 liter dies after about 30-45 minutes

Mical, I also recommend checking the anti-siphon valve. Mine got partially clogged, and restricted fuel to the carb. The Anti-syphon vlave is usually located in the fuel tank pickup tube. If you remove the pickup fitting from the tank, see if the pickup tube unscrews from the 90 degree elbow. Mine had a dirty filter screen.

 

[bandsaw48]

Re: 1990 4.3 liter dies after about 30-45 minutes

Mical, <br /><br />I believe the tube you mentioned is not the fuel line but the fuel pump vent tube which allows fuel leaking across the fuel pump membrane to be pulled into the carb to be burned and prevent a potentially dangerous situation where fuel leaks into the bilge. If so, that tube has nothing to do with fuel delivery to the carb but it does need to be replaced if clogged.<br /><br />Greg,<br />Sooner born, sooner bred... hopefully the rest takes a while.

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

I checked everything, the anti-siphon valve was not clogged, after some work i finally got the elbow off of the gas tank and and there was no screen there was a little valve inside the tube that if you blew on it you could blow air through, but neither one was clogged. Im starting to go crazy. I took it out on the water today and when it started to die i could spray carb cleaner down in the carb and it picked up so i know its not getting fuel. I think im just going to take the carb in and have it rebuilt and if that doesnt fix it then i guess the only thing left is the pump.

 

[Reel Poor]

Re: 1990 4.3 liter dies after about 30-45 minutes

Did you check the fuel filter in the carb? If you unscrew the fuel line from the carb the fuel filter is inside the big nut that the line screws into.

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

yes i checked the filter in the carb, and the filter on the pump.

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

does anybody know what a good price to rebuild a carb is?

 

[Bondo]

Re: 1990 4.3 liter dies after about 30-45 minutes

Originally posted by mical:<br /> does anybody know what a good price to rebuild a carb is?

About an Hour or 2 at the prevailing rates in your area......Plus Parts.......<br /><br />And,...... The Symptoms say it's Not the Carb....Bad Carbs don't run for a 1/2 hour,+ Die,.... Bad carbs Die Much Quicker...... <br />But it Could be.......<br /><br />It Still sounds like it's just Not getting gas TO the Carb.....

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

when i took it out last night it started acting up almost imediatlely so it is getting worse. think the diaphragm in the fuel pump has a hole in it possibly?

 

[Bondo]

Re: 1990 4.3 liter dies after about 30-45 minutes

think the diaphragm in the fuel pump has a hole in it possibly?

EVERYTHING between the Tank Vent,+ the Engine is a Possibility...........<br /><br />You can Either Diagnose it,........<br />Or,.....<br />Throw Parts at it, til you get it Right..........That's up to You........

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

which hose is the tank vent, is it the one that gas comes out of when the tank is full from re fueling?

 

[vipzach]

Re: 1990 4.3 liter dies after about 30-45 minutes

Originally posted by mical:<br /> which hose is the tank vent, is it the one that gas comes out of when the tank is full from re fueling?

yes, that is probly the vent hose. It will be a hose that runs from the tank to the back of the boat. What hose was full of junk before? Was it the the line feeding the carb or was it the clear hose that goes back to the fuel pump? How you done a flow test to see if your pump is supplyong enough gas? Can you see or hear the gas squirting into the carb when you pump the throttle? where in OK are you at?

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

I am in Edmond, have not done a flow test, when i fuel up gas comes out of the back when it gets full so the vent hose wouldnt be clogged, yes gas squirts into the carb when you pump the throttle, whenever it starts to die you can hear that the gas isnt spraying and you can spray carb cleaner into it and it picks back up and runs smooth and when you stop spraying it dies. the hose that was clogged was the clear one from the carb to the pump so thats not the problem

 

[mgeorge15]

Re: 1990 4.3 liter dies after about 30-45 minutes

so rebuilding the carb didnt fix the problem, i think my next step from reading other forums is replacing the fuel pump, everything else checks out.