Wire harness for 2000 mercruiser 4.3 Vortec carb engine

[dlogvine]

1. Can the wire harness for 1995-1997 (could be earlier, since the engine had a mechanical fuel pump) Mercruiser 5.7 be rewired for the 2000 Mercruiser 4.3 Vortec Engine. I looked at the wiring diagrams and they are pretty similar. One difference was the fuel pump wire and the other was a different type of Thunderbolt IV distributor connector. The reason for this question is obvious - I have an engine wire harness for the older Mercruiser 5.7 engine and a newly rebuilt 2000 Vortec block with most of the accessories. I can install another rebuild engine 1993 4.3 Mercruiser, it has a harness and is complete, however, I got an almost complete accessories set for a newly rebuilt 2000 4.3 vortec engine without the wiring.
2. Another question concerning the same engine, I have a 2000 Larson 180 hull without wiring and drivetrain in excellent condition, that I am trying to rebuild. I got a complete Alpha One Gen 2 outdrive, transom plate, bellhousing and trim pump set. I have a dashboard to engine wire harness from 1993 Larson with 5.0L v8 engine. At the first sight it looks similar to the one I need, do you know of any differences between 1993 v8 and 2000 4.3 v6 Mercruiser dashboard to engine wire harnesses that need to be addressed?
Thank you

 

[achris]

Grab the manuals for each of the engine and compare them. The only obvious difference would be a TKS carb. If you replace the TKS with a conventional carb (with electric choke), there shouldn't be a problem. Check things like alternator positions too. The TB-IV connector... If you buy a TB-V conversion kit, it comes with a plug adapter.

Chris......

 

[Scott Danforth]

Most of the harness is universal/generic. As Chris mentioned, start with the wiring schematics

 

[dlogvine]

I looked at 5he wiring diagrams, they are similar for v6 and v8. However the connectors for the thunderbolt ignition module that is attached to the distributor and the one on the harness are quite different. I wonder if there any place where I can buy just a male wire connector to match?

 

[dlogvine]

I'm trying to post photos of these connectors but for some reason cant do this. Will try later

 

[dlogvine]

[No message]

 

[achris]

Yep, standard TB-IV module. But some moron has turned it upside down. :facepalm: That might make it easier to plug in and out, but it traps water, the reason Merc mounted it with the plug DOWN in the first place. It also brings the wires in the harness inductively close to the HT leads.

Chris......

 

[achris]

Just done some research. The original TB-IV connector was a separate 'mini-harness' that plugged into the module and had independent connectors (not part of the main harness) to the coil and the rest of the harness. The new harnesses for the current TB-V modules have the connectors to the module integrated with the main harness. If a TB-IV module fails, the replacement is a TB-V module, complete with an adapter so the old TB-IV mini-harness can be removed and the new adapter put in its place. I can't find a part number anywhere for this new 'mini-harness'. It looks like it's only available as part of the TB-V supersession.

As I know these connectors aren't 'Merc-specific', I'd be looking around at Delphi connectors and see what matches up. I'm sure you have an agent for Delphi not too far away. We have one where I am, and if we have one, there's got to be MILLIONS around. You have the new TB-V module. Just take that off and take it with you to the agent. I'm sure they'll be able to match it up. A few years ago I was trying to connect the engine can-bus to my new sounder. I wasn't will to pay Merc's stupid dollars for a connector, so I sourced it from the Delphi catalogue. Still didn't work because Merc 'can-bus' isn't 'standard'. You need the Merc 'Gateway 2000' for it to work. :facepalm: And that's 'stupid dollars', on steroids!

Chris.......