Old Yamaha 663 55hp Outboard

[Coyleben]

Hi everybody, I have acquired an old 663 55hp 2 stroke. She’s in pretty good shape to be honest and I’m wanting to install it on my Rib. I’m struggling to find any info/ wiring diagrams for this engine anywhere. What I would like to do is install a Rev counter, but without wiring diagram, and pole numbers this will be difficult. Would anyone here be able to help me out?

thanks in advance.
Ben

[boscoe99]

What are the rest of the numbers?

[Coyleben]

Thanks for the reply it’s a 663 55AM

[99yam40]

do you have the production date?
and serial #
I am sure Boscoe will come up with info for a motor over here close to yours some how, if you give him enough info.

[boscoe99]

663 is the prefix for the engine ID. Following the 663 there should be a letter. Most likely L. Then some numbers. We need those numbers.

When the motor left the factory there was a sticker on it (left hand clamp bracket) that had the complete ID and the model on it.

[boscoe99]

Yamaha USA offered some 55 HP models for several years. C55's and CV55's.

Chances are that the parts that fit any of these motors will work on your motor.

https://www.boats.net/catalog/yamaha...ard-by-hp/55hp

More than likely the wiring diagram will look something like this:zc55.jpg

[boscoe99]

6 pole setting.

[Coyleben]

Thanks for the responses, I’ll go out now and get the code off the data plate. Thanks

[Coyleben]

663 l 55070

[boscoe99]

Looks to be circa 1977. An oldy but goody. Before Yamaha started providing models here in the USA.

[Coyleben]

Thank you. Yes she’s old. I just need to find out which wire is the signal wire from the coil in order to hook up a tachometer. I’m guessing this engine has no other data feeds, eg water temp or speedo. All info on this engine is greatly appreciated.
Thanks

[boscoe99]

The green wire in the 7 or 10 pin harness is normally the tachometer output lead.

Now if your motor does not have a rectifier or a rectifier/regulator then a green wire from the lighting coil can be used for the tachometer input lead. Find the green leads coming from under the flywheel. Where do they go? Are they connected to a device or not? There should be an unused bullet connector that is available for the tachometer.
z55.jpg

[Coyleben]

Very knowledgable, thank you!!

This looks like you’re referring to?

[Coyleben]

Hello again, thanks for the previous, I now have a rev counter wired in. The green bullet connector worked a treat.

my next question is on the charging output to the battery, as it stands my battery reminded are only connected to the starter motor itself and to the solenoid below it, where is the output from the coils to provide a charge feed? And how much power does this produce?

many thanks again

[Sarah4521]

Hey guys I just acquired the same outboard motor 663-L- and im having problem understanding what each wire is for. Im a novice and just started working on a boat rewiring. Can you guys help?