25 hp mercury serial number question.

[hardwater fisherman]

I bought my first Mercury outboard today. And I am a little confused about how to find out what year it is. The person I bought it from advertised it as a 1992. And when I was there he said around 1990 to 1992. The serial number is OG234977. To me it looks more like a 1995. I checked here at IBOATS and the only serial number starting with an OG is 1995. It states that 1995 25 hp is OG112450. 1990 starts with a C and 1991 thru 1994 starts with a D. Any help is welcome thanks.

 

[GA_Boater]

I can see why you are having trouble. The motor is either a 1994 or 1995, but Merc parts are ordered using the serial number. So it shouldn't cause any problem.

 

[hardwater fisherman]

Ok thanks. The decals look the same for 1994 and 1995. So that makes sense. EDIT It is a manual start with a long shaft if that helps to narrow it down.

 

[Fun Times]

How sure are of 0G234977 being the exact number? Running the number seems to indicate the engine to be a 20 HP vs being a 25 HP.

The Model number is coming up as 1020211RD which makes it a 1995 MERCURY 20 MLH. Parts guide part number 90-1858394 Service manual part number 90-826883R1.

 

[GA_Boater]

I see what you mean, Fun Times. Got both sets of serial number from Maxrules. :noidea:

 

[hardwater fisherman]

That is the serial number and if it is a 20 it has a 25 cowl on it.

 

[Fun Times]

That is the serial number and if it is a 20 it has a 25 cowl on it.

What's odd or surprising is most sites don't seem to be producing an actual parts guide for your exact number. One is but to help better to get inside it, use a 0 vs an O, https://www.mercurymarine.com/en/us/.../parts-catalog

The reason i asked is sometimes the importance of using the exact number could mean the difference in complete engine size such as these for example. 0G234976 = 1995 15 HP MERCURY SEA PRO SIDE SHIFT 15 MH/ALT Model number 1016207RD.

0G234978 = 1995 MERCURY 25 HP MH Model number 1025201RD Parts guide covers 20/25/JET 20/SUPER 15/15XD/25 SEAPRO/MARATHON 2 CYLINDER

You may have to try checking for any numbers on the carburetor to help determine (know for sure) the engine HP size. In the notes under the parts guide for the carburetor is some numbers such as WMC-53A OR WMC-44, etc..

 

[hardwater fisherman]

I think it is a zero before the G because looking at it closer the G is larger then the numbers that follow it. And 234977 are the same size as the zero in front of the G. So it should read 0G234977.

 

[flyingscott]

You have a 1994 1/2 to 1995 model 25 hp your motor is a mid year change. I bet because of mercosil block was used on yours. look at the throat of the carb if it looks the same straight through it is a 25 hp motor. If it looks like it narrows pretty drastically it is a 15/20 hp carb. The 15/20/25 hp motors will come up under the same parts list because they are the same motors with some detuning for the smaller Hp versions.

 

[hardwater fisherman]

No Title

The carb looks like it necks down. There are numbers stamped on the side of the carb. The numbers are 3534 and under them is 44. I think this means it is a 20hp. If so does this mean that the cowl is from a 25hp motor? Or the carb is off a 20hp?

 

[hardwater fisherman]

No Title

Just so you can see that the cowl says 25hp. Also it looks like cowl and the rest of the motor have been together for a while. There is some chips in the paint and the rubber on the cowl is damaged in the same area.

 

[Fun Times]

Carb number 44 = 20 HP. http://www.crowleymarine.com/mercury...cfm?mdl=ANOPHI

http://www.iboats.com/MERCURY-20-HP-2-CYL-1994-1998/dm/view_id.1701438

The cowling may have gotten mixed up somewhere along the line possibly even from new at the selling dealer. Besides the sticker, everything indicates it to be a 1995 20 HP.

Have a close up photo of the two serial numbers for possible future reference of similar situations as these do come up from time to time on the forums....https://www.perfprotech.com/blog/mar...-number-number

 

[hardwater fisherman]

That is not very good news. I am putting it on a boat that I thought a 25 hp would be marginal and now I find out it is only a 20hp. So what would make it a 25hp just a different carb? Or just a different jet and throttle valve?

 

[flyingscott]

Can you put a pic up of the side of the carb with the throttle linkage. Also look on the side of the block with the shifting linkage and on the top jug see if it says Mercosil on it. To make it a 25 you would need the Carb.

 

[hardwater fisherman]

No Title

 

[flyingscott]

Looks all original so just get a 25 hp carb for it. One trick you can buy the earlier 25 carb with the different throttle set-up and swap out throttle rods. Just make sure you buy the carb with the plastic spacer in the pump.

 

[hardwater fisherman]

OK thanks.

 

[hardwater fisherman]

Also thanks to all who responded. I learned again some things are not as they appear.