2001 Mag MPI Alpha lugs

[kirkj]

2001 Mag MPI Alpha lugs.
I have a 2001 Rinker Captiva 212
Boat #10243880
Engine serial# 0M007347
350 Mag MPI Alpha. I bought it with a cracked block so I never drove it to see how it was. I replaced the motor with a reputable remanufactured engine and took it for a spin. Now the problem. When I pull a tube or a wake board and try to go to WOT the engine goes to 2800 rpm and lugs there. It will finally get past 3000 rpm and goes to 4000 rpm. The manual says it should go to 4300 rpm. If I'm not pulling people it will lug at 2800 for a second and go to 4000 rpm. I've replaced the fuel pump, fuel regulator, bypassed the too cool system and installed a fuel pump and regulator on the side. The manual says 40 psi, so I adjust it there. The boat just smokes and lugs. I put it down to 15 psi and it lugs. I've replaced about all of the parts on the engine. There's an aftermarket prop on it. Could that be the problem? I'm at my wits end with it and about to sell it. What can I do?

 

[alldodge]

Fuel pressure for your serial number should be 30 psi according to manual 24

What is connected to the Schrader valve and why is the Temp wire not connected? Now it that wire is Tan/Blue stripe then it's the Temp Alarm

The manual says 40 psi, so I adjust it there. The boat just smokes and lugs. I put it down to 15 psi and it lugs.

How are you adjusting the fuel pressure?

You have a MEFI 3 ECM and need to have it scanned to see if there are any codes.

Did you have the injectors cleaned and flow tested?

 

[kirkj]

The temp wire must have fallen off when I was looking around. It was hooked upwhen trying to drive it. That's a fuel pressure gauge to test the fuel rail. I bypassed the fuel pump and regulator with an outside fuel pump and an adjustable fuel regulator.
I took it to a tech to check timing and codes and he said the timing was on and there were no codes. I replaced the injectors and no change.

 

[alldodge]

I bypassed the fuel pump and regulator with an outside fuel pump and an adjustable fuel regulator.

Ok, so does your adjustable Reg change any from idle to WOT?

I replaced the injectors and no change.

For a motor that was just rebuilt and installed it sure looks like it has not been taken care of. What manufacture did you buy your injectors from, or did you get them from Amazon or Ebay?

Did your problems start right after the install of the new motor or has it been good and showed up later?

 

[kirkj]

The pressure does change from i idle to WOT.
I put the engine in 10 years ago and have been working on it off an on since then.
I bought new bosch injectors.
I don't know if it was like this before because the engine block was cracked and not runnable.
There was no change in it running with all the parts replaced.

 

[alldodge]

Let me ask another way
You've had the motor for 10 years, has it "always" run like this since to motor was installed?

 

[Bt Doctur]

sounds like you replaced a 5.7 with a 5.0 and you lost about 60 horses

 

[kirkj]

Let me ask another way
You've had the motor for 10 years, has it "always" run like this since to motor was installed?

It has always run like this.

 

[alldodge]

It has always run like this.

ok, thanks

Need to get some readings from the motor when its running. To do this you need either Diacom (best) or at least Techmate Pro. These are made by Rinda and cost some.

With out this you can try to measure voltages at the TPS, MAP and Temp sensors and record them at different RPM's so they can be compared to the manual. With it making to 2800 without much trouble and then it lugs, I would think the ECM is seeing and issue and may be retarding the timing or the fuel.

Wonder if the ECM is seeing a knock, again need a scanner

Being a MEFI 3 you can see if there are codes with a 12V resistor LED or a digital voltmeter with a tone option and a paper clip. Install paper clip in the DLC pins A/B, also install LED of connect voltmeter. Turn key ON (motor off) and count the flashes

Have you set the motors timing using the paper clip only?