New Ignition Switch - Merc 54211 to a Sierra MP41000

[Hardcore Hardman]

Hello, first thank you everyone for all for the excellent posts and answers I have used for years when fixing my boat. I have come across something now though that has me stumped and the related posts is a bit over my head. Please help me out if you can.

I need to replace the ignition switch on my 650 Merc Thunderbolt outboard. (Serial 7058444) The part I am replacing is merc #54211 and it is a five post switch. There was four wires to it when I opened it up. I am unsure how to connect these four wires to the replacement part I have, a Sierra MP41000.

The reason I need to replace it is it was damaged when somebody broke the key off and when they removed the key they put too much pressure on the encasement cracking it and it was only a matter of time until I was not going to be able to start it in the middle of the lake. It was still working, but very fragile.

I am not a wiring expert here, so correct me if I am wrong but I am assuming based on my reading that the four existing wires are: 1) Choke 2) Battery 3) Ignition and 4) Solenoid. The problem is I am not sure which wire is which so as to attach them to the new switch. I think I am able to discern the Solenoid and Choke by looking at how they are wired within the control box, but I am not sure about the battery and ignition wires. The color coding does not seem to be followed the last time this was worked on. My thought is though that I would label the wires as I took them off the old switch as to how they were lettered. If I know what old switch letters are I should be able to match them to the letters on the new one. Am I wrong? If I am correct could I get some conformation as to what posts on the merc 54211 are?

Thank you all in advance. Please spell it out for me as I am not much of an expert at all for wiring.

Here are some pictures as to what I am looking at:
This is the old one, 54211.
This is the new one:

 

[NicoPags]

What colors do you have? I did a few searches using just the original key switch, but a model number would have made it easier too for future reference.
separate choke button or no?

 

[NYBo]

Welcome to iboats!:welcome:

My thought is though that I would label the wires as I took them off the old switch as to how they were lettered. If I know what old switch letters are I should be able to match them to the letters on the new one.

Yep, that will work.

 

[Hardcore Hardman]

NicoPags - thanks for looking at this. Sorry yes the part number is 129 C51015. The colors I have are White / Black, green, red and black. I have a push button choke.

I tried the following combination: Green as the Solenoid, White/black as the choke, red as the battery, and black as the ignition. What happens is it will start by me turning the key and pushing in key (the option on this new switch is a choke I guess), but as soon as I let the key back out it stops.

Thoughts?

 

[NicoPags]

yea if it kills the motor than something isn't quite right and your Run positions are wrong. Try this.

White/Black Choke to post C on the new switch, Green to post S, Red to post B, Black to post I.

Just curios, have you traced the wires to their respective parts. Like are you sure your choke solenoid is the white/black and Starter solenoid is Green etc?

 

[NYBo]

Usually, black black/white are both magneto, IIRC.

 

[Hardcore Hardman]

Okay so I have installed the new switch and it is working correctly. To save the next person some time and effort here is the answer to my question above.

Below is where the wire was on the 129 C51015 Switch, what that wire is and the letter it should be on the MP41000.

White / Black Wire was at F - This is the ignition wire - Attach to A on the new switch
Yellow (Above I said was green, mix up) was at B - This is the Solenoid wire that runs through the neutral switch - Attached to S on the new switch
Red was to E - this is the power - attached to the B on the new switch
Black was at M - this is a ground - attached to either of the M's on the new switch, although the way this particular ignition works it is not even required.

Also if you want to activate the push choke feature of the new switch, connect the Grey wire to the C post on the new switch. I did that and it worked better then my old push button.

Here is also a warning when installing a new MP41000 switch. I used a soldering iron to install the new switch which was not a good idea. I figured the old one was soldered so why not. The new switches though are more sensitive to heat, add that to the fact I needed to heat it up a few times to get it right I actually melted the connection inside the switch and it stopped working although it looked fine. I ended up having to purchase a new switch and the second time around I used connectors and heat shrink. This second way was also much easier to have the wires tucked in nice to fit in the small space.

Also wiring diagrams are supper useful even if they seem overwhelming at first. This site had some excellent ones: http://www.maxrules.com/mercwireindex.html

Now to go fishing!!! Thanks for the efforts to help NicoPags and NYBo.

T