3.0LX Hesitates at Wide Open Throttle

[em1234]

Hello all. I'm new to this forum and boating in general.

I have a 1996 3.0LX that runs great except with the throttle wide open. Up to ~3800 RPMs no issues at all. As soon as I get above that I get some significant hesiitation/sputtering. When I drop the RPMs its fine again.

I just tuned it up and had the carb and timing professionally adjusted. Since these were done I've had it out twice and had no issues the first time. This all started about half way through my second outing.

Any ideas on what to check would be appreciated.

Thanks

 

[Don S]

Re: 3.0LX Hesitates at Wide Open Throttle

Do you have a water seperating fuel filter? If not, you should get one. Have you changed the fuel filters in the pump and carb?

 

[towman818181]

Re: 3.0LX Hesitates at Wide Open Throttle

did you change fuel filters and water seperator if so equiped did you refuel since then

 

[em1234]

Re: 3.0LX Hesitates at Wide Open Throttle

I changed the fuel pump filter several months ago. The boat does not have a water separator.

Could the pump be going bad or need cleaned?

 

[Bondo]

Re: 3.0LX Hesitates at Wide Open Throttle

I changed the fuel pump filter several months ago.

Ayuh,... And it stayed Clean,.. Right up til your last boat ride...

It's No doubt a Fuel Delivery Issue,... Exactly What, you'll have to figure out...

 

[sgajan]

Re: 3.0LX Hesitates at Wide Open Throttle

I am having the exact same issue. Its like the motor just cuts out and starts missing. Im thinking that it may be the fuel pump not delivering enough fuel at that higher rpm.

 

[Bondo]

Re: 3.0LX Hesitates at Wide Open Throttle

Im thinking that it may be the

Ayuh,... Diagnose it,.... Guessing gets Expensive....

 

[sgajan]

Re: 3.0LX Hesitates at Wide Open Throttle

I guess my question is how to differentiate between a carb needing a rebuild for not letting enough fuel through or the fuel pump not delivering fuel at the rate needed? From my searching I am finding answers of one or the other. So it seems like a coin toss right now.

 

[maxumized]

Re: 3.0LX Hesitates at Wide Open Throttle

It would be worth while to try the fuel delivery vacuum test and pressure test to ensure things are within spec.

Instructions here:

http://forums.iboats.com/showthread.php?t=283363

 

[em1234]

Re: 3.0LX Hesitates at Wide Open Throttle

I took the pump fuel filter off today and found that it was crushed on one side. The other side is supported by a small metal rod. There was a fair amount of junk in the element.

Any ideas what would cause the filter to smash? Could this be the reason for my WOT sputtering?

Thanks

 

[cr2k]

Re: 3.0LX Hesitates at Wide Open Throttle

Fuel filter smash could be the problem. Also float level too low.

I would also check the points if it is a point ignition system. If they are too close they could be floating at high rpm. Or the coil or condenser.

99% of carburetor problems are electrical.

 

[sgajan]

Re: 3.0LX Hesitates at Wide Open Throttle

Just to let everyone know I found out what was my issue with the same problem. I had a bad alternator. I just happened to look at my alternator guage and it was only charging around 10.5. So i took it in and had it tested and it was bad. I put a new one on and the boat runs like it is new now !! no bogging, sputtering or hesitations. woohoo