Volvo Penta 4.3 Gi Conversion to 4.3 GL

mckaras

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Has anyone converted an originally Fuel Injected/TBI engine to a carbureted version? Wiring Harness connection is the same for the Gi and GL on my Chris Craft however I cannot even crank the engine with the key.

The kill switch is new, ignition is new, all the relays on the engine have been changed out as well. Still no power to the fuel pump, starter solenoid, etc. You can obviously use a remote starter to crank it which works without question but will not start the engine with the kill switch installed.

My question is whether or not the wiring harness from the GL is plug and play with a boat that was originally a Gi or whether the GL harness could possibly just be bad?
 

alldodge

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My question is whether or not the wiring harness from the GL is plug and play with a boat that was originally a Gi
No
The Gi applies a ground to one side of the fuel pump relay. The other side of the coil has full time 12V

The GL has one side of the coil which is full time a ground. The other side of the coil gets 12V from the key start circuit thru a doide, and to keep it energized it comes from the alternator once running
 

mckaras

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No
The Gi applies a ground to one side of the fuel pump relay. The other side of the coil has full time 12V

The GL has one side of the coil which is full time a ground. The other side of the coil gets 12V from the key start circuit thru a doide, and to keep it energized it comes from the alternator once running
I converted the engine to a Carbureted version including the wiring harness from a 4.3 GL. Even though the harness from the Carbureted version plugs up to the original plug on the boat side it will not work?

I put in a 4.3GL drop in engine. Most of the fuel system components looked trashed on the 4.3Gi for me to swap them over on top of the engine being busted from no winterization.
 

alldodge

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I converted the engine to a Carbureted version including the wiring harness from a 4.3 GL. Even though the harness from the Carbureted version plugs up to the original plug on the boat side it will not work?

Then it should work
What GL version is it?

Check around the relays to see if all grounds are connected
 

mckaras

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I converted the engine to a Carbureted version including the wiring harness from a 4.3 GL. Even though the harness from the Carbureted version plugs up to the original plug on the boat side it will not work?

I put in a 4.3GL drop in engine. Most of the fuel system components looked trashed on the 4.3Gi for me to swap them over on top of the engine being busted from no winterization.

Then it should work
What GL version is it?

Check around the relays to see if all grounds are connected
I will check tomorrow and get back to you, fairly old 4.3GL. Fairly Certain its a GL-A. I am getting 12V at the Ignition and the Kill Switch when I last checked it.

For the relay grounds are you talking about the pins that go into the relay holder or the grounds on the solenoids?
 

alldodge

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Here is the A version. Check wiring and note the 2 diodes. The diodes are inline with the wire. Use a ohm meter to check continiuity to make sure doide has not opened
VP wiring GL_A.jpg
 

Lou C

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I was thinking it could be one or both of the diodes. Switching back to a carb you’ll have less trouble sourcing parts and if you get good at cleaning and rebuilding carbs you can be relatively independent of mechanics.
 

mckaras

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I was thinking it could be one or both of the diodes. Switching back to a carb you’ll have less trouble sourcing parts and if you get good at cleaning and rebuilding carbs you can be relatively independent of mechanics.
It's been raining in GA last couple days and will continue so I will check once I get a chance. It definitely is a more simple system than the early Gi engines... The GXIs have parts which are not hard to source at all, those and the GLs are far easier to work on.
 

mckaras

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Here is the A version. Check wiring and note the 2 diodes. The diodes are inline with the wire. Use a ohm meter to check continiuity to make sure doide has not opened
View attachment 349956
Just had the chance to check the issue out, diodes are good. It looks like the problem is in the actual engine harness plug itself. If you turn the plug when it plugged in to the right the boat will start if you have someone turn the key. Any idea of how I can fix the plug by splicing it in with a new plug or any other ideas? I cannot seem to find it online at all, it's discontinued. Part #3856994
 

mckaras

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