Older 85 3cyl 2 stroke Model

[maheanuu]

My brother in law has developed a problem with his older Yamaha at high rpm's He changed out the fuel pump and the carburetor bank and nothing changed. He has an erratic miss at high rpms and all I can think of is the ignition.

We removed the flywheel and the pulser plate and its components look fine, I did a resistance check on all the circuits from the junction panel below and will provide all those readings below.

The First 3 wires entering the terminal block on the right side are the red blue and brown wires from the harness coming down from the pulser ring and these readings were made with all wires connected.

"Edit" Motor ID Tag Data

Yamaha 85AET 688 L 424901


Red - to Blue + 133.5 ohms
Red + to Blue - 133.5 ohms

Red - to Brown + 1.213 K ohms
Red + to Brown - 1.213 K ohms

Blue - to Brown + 1.082 K ohms
Blue + to Brown - 1.082 K ohms

Below are the 2 inner coils/sensors on the adjustable plate inside the pulser ring. The wire colors were White with yellow tracer, White with Black tracer, White with Red tracer and White with Green tracer. I have listed them below as W/yel, W/bk, W/red, W/grn.

W/yel - to W/bk + 131.5 K ohms
W/yel + to W/bk - 119.5 K ohms

W/yel - to W/red + 363 ohms
W/yel + to W/red - 363 ohms

W/bk - to W/red + 119.4 K ohms
W/bk + to W/red - 131.4 K ohms

W/grn - to W/yel + 118.5 K ohms
W/bk + 341 ohms
W/red + 118.5 K ohms

W/grn + to W/yel - 130.7 K ohms
W/bk - 347 ohms
W/red - 130.5 K ohms

I do not have any manuals on this engine and as I live in the middle of the south pacific, sometimes it is really difficult to get parts for engines or even get advice on repairing your own...

I have no ideas if these resistances are correct for in circuit measurements, or what the correct readings should be.

Any and all help would be gratefully appreciated..

[Aleutianwest]

whats the model

model number and year i might have a foriegn manual

[Remamanty]

Hi people

Hi, I'm new here, I don't know if "http://www.yamahaoutboardparts.com/forum2/older-85-3cyl-2-stroke-model-th15135.html#post51913" is the right place to post this, I am Mark from Australia.

[maheanuu]

model number and year i might have a foriegn manual

Thanks Aleutianwest I will get all that information if possible from the motor in question tomorrow morning and get back to you... Living in the outer islands here in the South Pacific sometimes can be very, very different. Down here, my bro in law used the carburetors and fuel pump off a running engine to arrive at the point we're at today. Being that work is rather difficult to find here in the islands, many times we must find ways to troubleshoot problems the most economical way that is possible as both the price of parts and of labor here are quite prohibitive, especially at this time of year with the holidays coming up. I am a retired USN Chief, and being the person in the family who speaks English and is computer qual'd to use the forums and try to find answers that will get the boat up and running to fish and also leave some cash in their pockets for the Holidays...

Thanks to all for the starting help and I will add more info before 09:00 Tahitian time (same as Honolulu)....

Maruru Roa!!