1996 Mercruiser 5.7L EFI/TBI

[cmoore]

I just purchased a 1996 boat and everything is original. I have replace the cap & rotor, plugs, plug wires, iginition coil, set valves, verified the injectors work, set timing, etc. The problem is when I get on the water and give it gas the thing will shut-off at 3000 rpm's and drop very low and then kick back in. If you let of the gas and run it at around 2800-3000 you are fine. I have diconnect the temp cut-out, stern oil switch, and jumpered the rev. safe switch also. It just seems like the ignition just shuts-off and then kicks back on.

 

[Bondo]

Re: 1996 Mercruiser 5.7L EFI/TBI

Did you change the Fuel Filters,..??........

 

[cmoore]

Re: 1996 Mercruiser 5.7L EFI/TBI

yes

 

[cmoore]

Re: 1996 Mercruiser 5.7L EFI/TBI

The gas pressure seems to be fine. it just seems to act up when I gas it and it stands-up or I turn hard. Seems lie some type of fluid switch might cause it to shut-off????

 

[Bondo]

Re: 1996 Mercruiser 5.7L EFI/TBI

Well,........... That's about as Far as I go with the Injected motors.........

Somebody will be along,+ Help you figure out Why your motor is running Out of Gas...........

 

[Don S]

Re: 1996 Mercruiser 5.7L EFI/TBI

You can change filters, you can do normal tuneups, but unless you have an OEM service manual, a DVM and REALLY know how to use it, the proper fuel pressure gauges, a way of reading the ECM, and any trouble codes, you really don't have a chance of finding the problem an an EFI engine unless you start throwing a lot of very expensive parts at it till you chance upon the right part.
Do you have the necessary tools, manuals, and abilities?

 

[cmoore]

Re: 1996 Mercruiser 5.7L EFI/TBI

Yes I have all except for the code reader which is 400.00. I'm very good with a meter I have been in controls for over 10 years. I have the manuals but they are not the actual OEM they are very similar. I have looked at the prints and I just need to know about a few things to bypass.

 

[Don S]

Re: 1996 Mercruiser 5.7L EFI/TBI

What outdrive do you have?

 

[cmoore]

Re: 1996 Mercruiser 5.7L EFI/TBI

Alpha One

 

[Don S]

Re: 1996 Mercruiser 5.7L EFI/TBI

The Alpha I Gen II drives have a shift interrupt switch. Disconnect it at the switch, then go for a run and see if your problem still occures.
In order to go back to neutral without possible damage to the cable or drive, be sure to hook the switch back up before trying to put the shifter back in neutral.