Mariner 25 model id help.

ryan_289

Seaman
Joined
Jun 8, 2012
Messages
60
A friend of mine dropped of an old Mariner 25 today and wants me to see if I can get it running for him. The serial number tag is gone. It appears to be one of the japanese built Mariners but im not sure if there is a way to determine the model number so I can order parts. Its definatly not one of the Mercury made 25s. It appears that most of the carb kits and impellers are the same for these except for the very early models. This one is tiller handle with electric start. The cowling has a metal Mariner emblem on the front with the "Mariner man" on it. Any ideas?
 

Fun Times

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8,776
The number stamped into the freeze plug is 551041
Could you double check the welch plug serial number? It seems you may be missing one number or letter someplace. If not, post a few photos of the engine, someone may recognize it. Also if the engine has a starter motor on it, sometimes there is a date code on it that may help too.

An example of a serial number,
mercury_serial_number_stamp.jpg
 

ryan_289

Seaman
Joined
Jun 8, 2012
Messages
60
Im pretty sure it is a 25C. The parts diagrams for that motor seem to fit. It looks crappy but I got it running last night and it seems to run pretty good. it had a little over 100 lbs compression and was even on both cylinders. I was hoping it would be higher but they are both the same. I need throttle cables, water pump parts, and i may go ahead and put a carb kit in it while im there. I also need to replace some wires to the starter and kill button that grounded and got hot.

Im also trying to figure out exactly how the bottom cowling is held down in the front. I see the rubber bushings in the back. I can wiggle the whole thing pretty good and the front i can pick up on. Is there a service manual on these anywhere on the net?
 
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ryan_289

Seaman
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Jun 8, 2012
Messages
60
Here are some pictures
 

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ryan_289

Seaman
Joined
Jun 8, 2012
Messages
60
Number on welsh plug
 

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ryan_289

Seaman
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Jun 8, 2012
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60
Well I went ahead and ordered parts on boats dot net for what they list as a 25c. All of the parts diagrams on that listing look right.
 

Mohawkmtrs

Chief Petty Officer
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Jan 13, 2010
Messages
560
Judging from the pictures and welch plug it's a 1979 Model 25EL (electric start, long shaft).

Yamaha used a 3 digit prefix.

Range for 1979: 695-550286 to 695-551275
 
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ryan_289

Seaman
Joined
Jun 8, 2012
Messages
60
If that's the case the power head has been swapped at some point. This motor is a short shaft.
 
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