Mecruiser 4.3l Help

[hit4thefence]

I have a 1987 searay seville. I currently purchased a new 4.3l and I have installed it. I have brand new spark plugs, distributor assembly, and fuel. It starts and idles fine but when under load it acts like its wanting more gas. Could this be a fuel pump issue? Im pretty sure timing is on but if you think this may be the cause let me know as well. Thanks.

 

[dubs283]

Re: Mecruiser 4.3l Help

Im pretty sure timing is on but if you think this may be the cause let me know as well.

welcome aboard!!

i have found it best to be 100% sure of the timing, do you know what the timing is set at now??

have you tested fuel pump pressure??

see here as well:

http://forums.iboats.com/showthread.php?t=295070

 

[Bondo]

Re: Mecruiser 4.3l Help

I have a 1987 searay seville. I currently purchased a new 4.3l and I have installed it. I have brand new spark plugs, distributor assembly, and fuel. It starts and idles fine but when under load it acts like its wanting more gas. Could this be a fuel pump issue? Im pretty sure timing is on but if you think this may be the cause let me know as well. Thanks.

Ayuh,... Welcome Aboard,... What killed the old motor,..??

You might have changed the motor, 'n Not fixed the real Problem.....

Test the Whole Fuel system, startin' at the tank....

 

[hit4thefence]

Re: Mecruiser 4.3l Help

Thanks for the warm welcome. I drained the entire gas tank then resupplied with new fuel. The old engine was not winterized properly. I dont understand why people do not do correct procedures and just winterize things. I purchased this boat at a great deal then said forget that old engine and replaced with new one. Im pretty sure timing is set correctly though. Im just curious about the fuel pump. Thanks for posts

 

[dubs283]

Re: Mecruiser 4.3l Help

Im pretty sure timing is set correctly though

again...how do you know for sure?? did you set it using a timing light??

Im just curious about the fuel pump

what are you curious about?? pressure/vacuum?? - only you can figure that stuff out, we have no way of seeing the pump or testing it for you

here is a link for testing the pump output:

http://forums.iboats.com/showthread.php?t=283269

 

[achris]

Re: Mecruiser 4.3l Help

Check that the spark is advancing. Before looking at the fuel system, make absolutely sure EVERYTHING in the ignition system is right.

You haven't given us much information on the new engine. What year is it? Balance shaft? Vortec? What fuel system (MPI, TBI, Carb/2bbl or 4bbl)? What ignition system (Thunderbolt IV, Thunderbolt V, MEFI, ECM/PCM555)?