Mercruiser 4.3L wire harness

jasonburba74

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I need your help; I have a Mercruiser 4.3L engine, and I'm doing an engine swap to a 5.0L. Had the motor sitting in my garage with the intent to sell it, but I have decided to put it in my Tahoe Q7i which currently has a 4.3L. My question is that the harness has a 4-wire plug coming off the main harness, and it has a label on it that says "Transom Harness." The 5.0 does not have a 4-wire plug anywhere on the harness. I am not sure what to do about it. Does anyone have any suggestions?
 

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What years are both engines and was one or both fuel injected at one point or another? any serial numbers handy?
 

jasonburba74

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What years are both engines and was one or both fuel injected at one point or another? any serial numbers handy?
Not sure of the years, but the serial number for the 4.3 is 1A072140, and the 5.0 serial number is 0L639572. Neither engine is fuel injected.
 

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Not sure of the years, but the serial number for the 4.3 is 1A072140, and the 5.0 serial number is 0L639572. Neither engine is fuel injected.
The newer engines started to change ways they connected to the transom assembly using plug type connectors vs terminal rings, etc..
The orange and brown? wires inside would be for the MerCathode Corrosion system and I believe I see a bullet type connector which ought to be for the trim limit and position senders mounted on the gimbal ring out side of the boat.
You may have to get creative to connect to the transom if you have and use any of the components of the transom assembly.

Merc part number 84-866727T01,​


Item number 14, https://www.marineengine.com/parts/mercury_marine_parts/sn/1A072140/4211025US/13798_40



www.boatingwithtr.com/members/pdfs/7a_28.pdf
 
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