Mercruiser repower with a 4.3 EFI

[newport dave]

Re: Mercruiser repower with a 4.3 EFI

Somebody better show me a service manual that shows ANY EFI engine using a Thunderbolt distributor. They all used either the Delco EST (Early) and the later used the composite one (for the life of me I can't remember the name) with the flat cap.

Don,
There was a brief period (1998 1/2 , 1999, and 2000) after they stopped using the Delco EST dist and before they went to the composite HVS dist that they used the T-Bolt distributor. I believe it was on all MEFI3 small block (and 4.3) EFI and MPI engines.

Check out the wiring diagrams in Service Manual 24, pages 4E-15 and 4E-17.

 

[Don S]

Re: Mercruiser repower with a 4.3 EFI

Thanks Dave, I rechecked and stand corrected. :redface:
He has a 4.3L and I did look at the wiring diagrams in manual 25, sure enough, one page showing the TB distributor.
Funny thing is, that distributor never shows up in the parts catalogs, and in the manual you have to specifically look for MEFI3 and understand what you are seeing to notice the wiring differences in the distributor.
I kind of got away from it for a while, but think I will go back to asking for a SN for Mercs and Volvos, since neither go by year on anything.

PS: Yea, HVS, I should remember that till at least tomorrow

 

[achris]

Re: Mercruiser repower with a 4.3 EFI

.... but think I will go back to asking for a SN for Mercs and Volvos, ....

Engine serial number is OL651284

 

[get-r-done]

Re: Mercruiser repower with a 4.3 EFI

So here I am one year later or so and still waiting on the repower. After several issues with installing a v6 where a 4 once sat I find myself back at this original question. How to make the bravo computer work with the alpha drive on this boat. My mechanic has done what DonS suggested by connecting the interupt switch between the distributor and ECM. Wired this way it kills the fuel delivery. There is no injector pulse width coming with things hooked up this way. Disconnect this switch the motor runs fine. Can't get it out of gear, but it runs fine. PLEASE HELP!!! Money and patience are running out.

Thanks

 

[Don S]

Re: Mercruiser repower with a 4.3 EFI

How to make the bravo computer work with the alpha drive on this boat.

You can't, get the right module for an Alpha, and it will work.

 

[Bondo]

Re: Mercruiser repower with a 4.3 EFI

Ayuh,... I'll preface by saying,....
I know next to NOTHING about the electronic managed motors,...
But,......
If you had an alpha shift Switch that was Normally Closed,+ Opened the circuit when tripped,...??...
And you wired the Igntion(keyswitch) through this azzbackwards shift switch,..??
Wouldn't that shut the motor off for the second there's pressure from the cable on that Switch,..??
Or,... Would the 'puter Gods send Smoke signals tellin' of your Failure,..??..??

 

[get-r-done]

Re: Mercruiser repower with a 4.3 EFI

Don,Thanks for the input. Do you or anyone else on the forum have a resource for this part. It seems it has been discontinued. The serial number for the motor is below.

Engine serial number is OL651284

 

[Don S]

Re: Mercruiser repower with a 4.3 EFI

The new number is 892800A01, just over $3500

 

[Tail_Gunner]

Re: Mercruiser repower with a 4.3 EFI

This should be as simple as going to the site below

http://www.obd2allinone.com/sc/toplevel.asp?cat=32

Give them a call and ask them to either reflash the ecu to the orignal merc specs with alpha drive or simlpy code the old ecu for a interupt

They are very well versed with mefi-3 its a very basic system..Id bet a 100 or two would get the job done.

http://www.obd2allinone.com/sc/details.asp?item=mefitune

There ya go..These guys are very good id stay with them

 

[get-r-done]

Re: Mercruiser repower with a 4.3 EFI

Thanks Tailgunner, I will be contacting them tomorrow. $200.00 is much easier to swallow than $3500. Thought I was getting a real gem when I bought this Bravo engine. Wishing now I would have waited for an alpha motor. Oh well to far into the project to turn back now. One more question for a rookie.... Last time I talked to the mechanic he tells me he is looking for a newer wiring harness to install in my boat. Says the motor starts and runs fine when connected to his test system, however when connected to my wiring harness there is no keyswitch wire for the ecm. Is there an adapter for this? I suggested just to jumper it, but he is concerned about safety.

 

[Tail_Gunner]

Re: Mercruiser repower with a 4.3 EFI

http://www.cpperformance.com/detail.aspx?ID=838

Theres a plug that will allow you to rewire your boat. Complete harness's are out there but they are outrageously expensive..Once you get into it its really pretty simple stuff ...