Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

scjakester

Seaman
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Aug 26, 2007
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57
Hi folks, I am repowering my 2003 Triton pontoon boat and wondering if I can get some direction. I'm replacing a 2003 75hp Mercury 4 Stroke with a 2004 Yamaha 40hp 4 Stroke. I have never swapped out an engine before but i think I can do it in a weekend.

Two quick questions:
---------------------
I'm hoping I can reuse my current control box, will all the cabling just snap back into place on the new engine or if not is there a conversion kit that I'll need?

Also, I would really like to reuse the existing console gauges, is there an electrical conversion kit or something that will let me use my existing console gauges (key switch, tach, voltage, tilt/trim)?

Thanks in advance to anyone that responds.

-Jake
Lexington, South Carolina

repower-pontoon-yamaha-4-stroke-3.jpg
 
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yamatech43

Petty Officer 2nd Class
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Feb 9, 2011
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188
Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

I think you need to see if the Mercury is a "push" rather than a "pull" box....that is for the throttle...other than that you should be able to screw on the correct ends for the cables for Yamaha....you can find the color codes on here, as I'm sure you know they won't match up for the wiring so you will be best off cutting into the boat's main harness above the waterline(for dryness), and splice in the Yamaha plug there so you will have the plug connection proper in the motor.
See it there is a trim sender under the Yama on the tilt tube, this should work with most gauges, you will have to set it of course(adjust). No kit that I know of, but seems like there would be, you could call a dealer and ask if anybody(3rd party) offers one, they have the BIG catalogs. Good luck.
 

99yam40

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Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

not sure you will be happy with that 40 after having a 75 on it before.
Just a thought
 

Bamaman1

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Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

You'd be better suited to use the same brand motor. Switching to a different brand may cause you to have to purchase some very expensive components. Remember, everything marine is expensive.

The only size motor I'd ever use is the boat's maximum rated horsepower motor--or one size less. But, little lakes or a lake with a maximum hp law sometimes require such small motors. When you put a 40 or 50 on a pontoon, you have to run them to death to get anywhere.
I prefer a big motor cruising at half throttle--quietly and efficiently.
 

Silvertip

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Sep 22, 2003
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Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

He probably already has the engine so telling him what he shouldn't do HP wise is a moot point. Let's answer his questions.
 

scjakester

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Aug 26, 2007
Messages
57
Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

@Silvertip - Yeah, I already purchased the outboard. I bought the boat with the original Mercury blown up (water in the oil from saltwater eating up the head gasket and head). I'm sure Mercury makes a good product and if it weren't for the salt water this would have probably been a great motor, but I have personally had just plain awful luck from the two others that I've owned in the past. It was going to be either a Honda or Yamaha no matter what. I'm not out to break any speed records, I just want something extremely dependable to leave in the water up at the lake and putter around fishing on the weekends. I plan to physically install the motor onto the transom sometime this evening, as far as the wiring... well.... If I'm brave enough to tackle it, maybe this weekend. :)

@yamatech43 - I know it isn't your job to babysit me (no matter how much my wife would probably pay ya to do so!) but can you point me in the right direction with some links on the wiring? I'm also guessing that I'll need to purchase some sort of cabling ends to use the existing binnacle control's cables (it is a push style, if I understood your post correctly). Maybe if you wouldn't mind shooting me a link to them, I would really appreciate it. I have an electrical background and I feel *reasonably* comfortable that I can take care of the installation if I can get my brain around the wiring. I will have a lot better idea of the style differences this evening, I just don't want to burn anything up! It was dark last night when we picked up the new outboard. Check it out! It has 23 hours on it. :)

IMG-20120214-00094.jpg
 

99yam40

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Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

Looks good, did they say why they were getting rid of it after only 23 hours on it? were they having any problems with it?

I have heard the carbs on the F40 were something harder to deal with than others, but have no idea why. maybe small jets and orfices. make sure you keep a good 10 micron filter/water seperator on to keep carbs clean and pick up a Yamaha service manual for it if you plan on doing the work on it yourself.
Here is something on wire colors that may help in the long run, but I do not have schematics for the 40 4 stroke
http://continuouswave.com/whaler/reference/wireColorCode.html#Yam
 

scjakester

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Aug 26, 2007
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Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

@99yam40 - Thank you (sincerely) for the info, very helpful. The outboard was purchased new rigged as a package on a Carolina Skiff, but the previous owner was unhappy with the performance when he had it loaded down so he swapped it out for a 60hp. He saved it in the garage thinking he'd buy a big duck boat and convert it to a tiller, but never got around to it. I went down to one of the Yamaha Authorized Service Centers here in Columbia, SC on my lunch break trying to buy a service manual, but his attitude was all about "bring-it-in-and-we'll-do-it-for-you". I kinda' want to give it a go myself first and then who knows, it may come to that but I am at least going to try it.
 

yamatech43

Petty Officer 2nd Class
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Feb 9, 2011
Messages
188
Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

ok, it should work(with a little work)....for the wiring codes just look up to top of screen and do two searches 1)Mercury wiring color codes and 2)Yamaha wiring color codes...or do the same on google. Now I didn't see what boat you have, but hopefully it's Merc rigged all the way and you won't have to get into a boat manufacturer's color codes(often the wiring in the boat, even in a main harness will be the maker's colors). At least you don't have to worry about the extra wiring for two stroke oil tanks and such....what you can't find just ask on here for...but shouldn't be any problem. Enjoy your new Yamaha.
 

scjakester

Seaman
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Aug 26, 2007
Messages
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Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

Thanks a bunch guys... I got the new 4 stroke Yamaha mounted on the boat and all the steering linkage working! Whoo hoo! Now I need to tackle the shift linkage and then the wiring. I have a lot more information now -- in a nutshell, I am replacing a 2003 Mercury 75hp 4 Stroke (model 1F75412ZD) with a 2004 Yamaha 40hp 4-stroke (model F40MCLH).


***** > Here are the connectors on the new Yamaha. What do the two smaller plugs (B&C) do?
Yamaha-F40MLHC.jpg



***** > These are the connectors on the boat's wiring harness. There are several other wires out that were connected. I am going to tone everything out tomorrow and try to draw a schematic of the boats wiring.
2003-Triton-Pontoon-Boat-Harness.jpg



***** > This is an adapter of some sort that was in use between the wiring harness and the old Mercury. It looks like it will plug right up between the boat's existing wiring harness and the new Yamaha outboard as well, but I don't want to try it until I can tone out all the cables. It physically fits together, but I don't want to take a chance on burning anything up!
Adapter-between-wiring-harness-and-outboard.jpg



***** > This is the binnacle box that came with the Mercury, I am hoping to reuse it but I may not be able to. It retracts to throttle and I think the Yamaha requires one that extends to throttle.
[/IMG]
binnacle.box.jpg



***** > These are the control cables that came with the Mercury. They look much different than the shift linkage on the Yamaha! The Yamaha linkage looks as though it uses a single threaded connector. Not sure if these can be converted or if I need to order new ones.
Control-Cables.jpg



***** > This is the shift linkage on the Yamaha.
Yamaha-shift-linkage.jpg
 

scjakester

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Aug 26, 2007
Messages
57
Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

Progress has been made! At least on the control side - I will be toning out all of the electrical wires this weekend. Just in case anyone else is struggling with something similar. The Mercury binnacle control above can do either Push-to-Throttle or Pull-to-Throttle depending on cable placement. The cable inside connects to a short lever inside that looks like a kids teeter-totter. When one side goes up, the other side goes down and vice-versa. I just had to move the cable to the other side of the teeter-totter thing, now both the shift cable & the throttle cable come up into the binnacle through the same hole. I did have to order a new set of cables though, the ones I needed to connect a Mercury binnacle to a Yamaha motor are called 600a series cables.

Many thanks to Bryan at Captain's Choice Marine in Lexington, SC. He spent about 45 minutes helping me yesterday evening, looking at the pictures, talking to one of their service technicians and helping me figure all that stuff out so I could order the correct cables.
 

99yam40

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Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

Hope it has the proper length of movement needed to open the throttle correctly, I guess they are the same.
Looked like your old cable ends were corroded and needed to replace anyway
 

scjakester

Seaman
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Aug 26, 2007
Messages
57
Re: Repowering from Mercury to Yamaha, is there a kit for the electrical and controls

I went up to the Yamaha-Marine dealer to get some assurance that plugging that adapter in would not burn anything up. Got back, plugged it in and the new Yamaha fired right up on the boat's Mercury wiring harness! :D Got the steering connected, got the ignition working, got the shifter working, got the throttle working and got the tilt/trim working. Still have some work to do with the gauges and the lighting, but the outboard is alive. (its.......... a.... LIVE).
 
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