Volvo Penta GS to GSi Engine Swap

[cmezzino]

Ok, I'm progressing on my rebuild and starting to think about the new engine. My current platform is Volvo-Penta 5.7 GS PLKD, SX drive with 1.51 ratio. (1997).

I came across a Volvo Penta 5.7 GSi PBYCCE that came out of a 1998 model boat. Both engines are of the same 94-00 charcoal color vintage.

It appears the GSi is TBI vs. carb and the GSi has an electric fuel pump vs. the mechanical one that is on my GS. My GS has non-vortec heads and I do not know which are on the GSi.

Both appear to have the same round "cannon" plug on the starboard side exhaust riser circuit breaker housing.

The other thread I read discussed a GS to GXi swap in which I read that a cannon plug adapter may be necessary because the GXi has a rectangular plug instead of a round one, so that thread did not appear to answer my question.

I would like to know if the GS and GSi engines will simply "plug and play" or is there any other significant modifications that would be necessary.

 

[GA_Boater]

Carb to FI is never plug and play.

 

[Scott Danforth]

check the wiring diagrams for the motor. however in your case it may be plug and play for a complete bobtail.

 

[cmezzino]

scott, I'll check my OEM manual. It contains both platforms, so I'll try to see if that helps at all. And yes, it is a complete bobtail engine with all accessories, computer, everything.

 

[Lubak572]

My 2001 had twin 5.7 GSI PEFS motors. They are TBI with vortec heads 280 HP. Mine also had the round plug but it is on the back of the starboard head by the distributor.

 

[cmezzino]

Ok, so I have attached images of the cannon plug for both of these engines and they are different. The first image shows the 5.7GS cannon plug which uses 9 out of the 10 pin ports. Pin #9 is the one that is not used. The second image is for the 5.7 GSi, which uses all 10 of the pin ports. Pin port #9 wire color for the GSi is "Green/Yellow" which traces back to the "diagnostic link connector/ECM" as seen in the third image.

All other pin port assignments appear to be the same except for this one. I'm assuming that this "diagnostic link connection" is the equivalent of an OBDII port on an automobile?

 

[Lubak572]

Yes the DLC is a plug with a cap on it where I plug in my laptop with diacom on it. So yes same as a car.

 

[cmezzino]

Update... I ended up going back with the same platform as before. Only difference was I did a 4-bolt main with #638 block casting instead of the original 2-bolt main with #880 block casting. All else is identical. Same roller camshaft/lifter style and mechanical fuel pump. Worked fine before.