yamaha powerhead parts from Mariner 25 hp motor without data plate

H

h2onxs1956

Seaman Apprentice
Joined
Dec 1, 2011
Messages
31
I has given a 25 hp Mariner outboard 10 years ago and it has 100 psi on 1 cylinder and 40 psi on the lower.
This motor has no data plate, the serial number plate has been knocked off or removed .
I was going to "trash" it untill I saw what even used one's were going for.
There are motor numbers on several engine parts with the Yamaha logo stamp.
Does anyone know how to access yamaha parts from just motor ids.
Does 40 psi on that one cylinder necessarily mean rings, it did not increase when I put oil in thru spark hole.
Would reed? valve ( it does have one ,shouldn't it?) or head gasket be more likely the problem.
Other than it doesn't have spark either.
Signed, moneypit investor
 
Don S

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: yamaha powerhead parts from Mariner 25 hp motor without data plate

Before you spend a lot of time looking for parts, pull the head and check the cylinder walls. If they are destroyed, you may need a new powerhead.
 
H

h2onxs1956

Seaman Apprentice
Joined
Dec 1, 2011
Messages
31
Re: yamaha powerhead parts from Mariner 25 hp motor without data plate

I did discover my engines Serial Number!
I checked several other motors and found the freeze plug number was the same as their data plate Serial Numbers.
 
C

carholme

Rear Admiral
Joined
Sep 4, 2010
Messages
4,845
Re: yamaha powerhead parts from Mariner 25 hp motor without data plate

What is the s/n and we can get you the parts lists and year of manufacture and possibly a service manual.

Gerry
 
H

h2onxs1956

Seaman Apprentice
Joined
Dec 1, 2011
Messages
31
Re: yamaha powerhead parts from Mariner 25 hp motor without data plate

Serial number= 695s 023705

Basic , pull start , plugs out, motor turning (the right direction) with 1/2 " drill motor, stop switch wires disconnected.

one stator= ignition= (brown wire) =244 ohms to GND, and spinning 220V on DVA.

one trigger= (white wire /red stripe)=106 ohms to GND, and spinning 9.99V on DVA.

3 wires into CDIGNITION = the brown, the w/r wire, and blk = GND.

4 wires out = blk to upper coil primary, orange to lower coil primary, Blk to GND, White to 'kill' switch devices.

No spark either plug.

Guts tell me ignition stator valid resistance and DVA voltage.

Trigger voltage seems low "to me".

Unable to locate THIS motors testing data.
Need good input to get good output!!

Seloc book leaves Everything up to speculation!!! I have found no useful information in it so far!

All the Mercury / Mariner info I've found so far is not for Mariners .
They say M/M on covers but then only ref it good for Merc Serial numbers ,ignition type, wire codes and testing data.
Any help in help in locating a true Service Manual or confirming my conclusion on this very basic of ignition configuration appreciated.
 
You must log in or register to reply here.
Top