87 Searay Seville 17.5 & Mercruiser 120 HP 4 cylinder Wire diagram

[SFORCES]

Re: 87 Searay Seville 17.5 & Mercruiser 120 HP 4 cylinder Wire diagram

Can you point me to were i can get a terminal and what kind and what resistor to get. What Gage wire should i get? could i just use the wire that is the original 87 wire harness and just cut the end's off? or is it better just to get new?

on the engine on the bottom right side i got some # 3849449 or it would be 8849449 can't tell also there is OH186 con2 i think that it's an OH in front of the 186 can't really tell. on the alternator it's say's 1100721 32a 6L17-12V neo how can i tell if it has an external regulator?

also can you tell me how to take off the side panel so if i need to run new wire i can.

HMM... Guess not..

 

[SFORCES]

Re: 87 Searay Seville 17.5 & Mercruiser 120 HP 4 cylinder Wire diagram

Take all the old wiring off the engine. Then buy new wire the correct size and color (when possible) and make a new wiring harness. You will have to use a terminal block instead of the round harness connector because they just don't match up.
You will also have to go to a Merc dealer and get a resistor wire to build your new harness with.

Problem I have, is I'm not sure you have a 69 motor there, or what it is. What alternator is on that engine now, does it have an external regulator? The ballast resistor is wrong for a true 69 engine should show a dual resistor.

If i can find the original breaker round connector etc. for what was original with this boat. can i then take those wire's and hook them to the engine in the boat now? like the pic below. but so i can use the original connector? or wouldn't that work. or maybe just cheaper to go with making my own wire harness?

 

[SFORCES]

Re: 87 Searay Seville 17.5 & Mercruiser 120 HP 4 cylinder Wire diagram

Hmm.. i guess from no more replies no one know's...

 

[SFORCES]

Re: 87 Searay Seville 17.5 & Mercruiser 120 HP 4 cylinder Wire diagram

Take all the old wiring off the engine. Then buy new wire the correct size and color (when possible) and make a new wiring harness. You will have to use a terminal block instead of the round harness connector because they just don't match up.
You will also have to go to a Merc dealer and get a resistor wire to build your new harness with.

Problem I have, is I'm not sure you have a 69 motor there, or what it is. What alternator is on that engine now, does it have an external regulator? The ballast resistor is wrong for a true 69 engine should show a dual resistor.

Don you still here reading this post? Can you help me out with this please? I told you what alternator said on it or don't you know? If so just tell me so i don't keep beating a dead horse. This is all new to me never had a boat.

 

[SFORCES]

Re: 87 Searay Seville 17.5 & Mercruiser 120 HP 4 cylinder Wire diagram

????

 

[fishrdan]

Re: 87 Searay Seville 17.5 & Mercruiser 120 HP 4 cylinder Wire diagram

How handy are you with wiring and following the diagram that DonS posted up?

Personally, I would buy a Mercruiser wiring harness the vintage of the boat and built for a 4cyl GM engine (120/140HP, 2.5/3.0L whatever it was in 87) and connect that harness to the engine,,, following Dons' diagram. You'll probably have to get a used harness and hopefully all the wire locations match up to the old engine, if not you might have to re-wire some things. I have a 2001 harness on my 72' 140HP engine, worked prefect, but not everything is connected to the older engine.

OR, do as Dons suggested and buy a terminal block, omit the plugs and wire everything to the terminal block. If doing this, follow the boat's wiring harness with the proper sized and colored wire to the engine, proper crimped and sealed connections. The tough ($$$) part of this approach will be buying all the different types of wire, in short lengths. Maybe buy a Mercruiser dash to engine harness, rob the wires out of it since it should (might, maybe...) have the proper colors and gauges of wire, and use those wires from the terminal block to the engine.

 

[SFORCES]

Re: 87 Searay Seville 17.5 & Mercruiser 120 HP 4 cylinder Wire diagram

How handy are you with wiring and following the diagram that DonS posted up?

I think i can figure it out.


Personally, I would buy a Mercruiser wiring harness the vintage of the boat and built for a 4cyl GM engine (120/140HP, 2.5/3.0L whatever it was in 87) and connect that harness to the engine,,, following Dons' diagram. You'll probably have to get a used harness and hopefully all the wire locations match up to the old engine, if not you might have to re-wire some things. I have a 2001 harness on my 72' 140HP engine, worked prefect, but not everything is connected to the older engine.

I have the original harness that came with the boat. and the one that came with the 120hp replacement engine. but the pin's on the plug that goes to the engine is 8 pins but there arranged differently.


OR, do as Dons suggested and buy a terminal block, omit the plugs and wire everything to the terminal block. If doing this, follow the boat's wiring harness with the proper sized and colored wire to the engine, proper crimped and sealed connections. The tough ($$$) part of this approach will be buying all the different types of wire, in short lengths. Maybe buy a Mercruiser dash to engine harness, rob the wires out of it since it should (might, maybe...) have the proper colors and gauges of wire, and use those wires from the terminal block to the engine.

ok he also said get a merc resister wire to for the engine. i'm not sure what that is. can you show me what it look's like and were i need to get it. I would just like to use the original wire harness and be done. but if i can use the original wire harness and just cut the plug off the end that goes to the motor and wire it to the engine i guess that would be ok too. I guess i'm just confused :0(...

 

[SFORCES]

Re: 87 Searay Seville 17.5 & Mercruiser 120 HP 4 cylinder Wire diagram

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