115 HP No compression #3 cyl. Big fix? And what year is this Merc?

[Buck Horn Deer Farm]

Helping a friend with his old motor that lost power. I'm retired and have time to tinker with it. He said it has a scored bore in no. 3 cyl. (looked through an inspection plate?) I want to get a repair manual but not sure of the year of this motor.
It is a Mercury 115 HP, 1150 Thunderbolt ignition, Direct 6 charge, power trim, ser. no. 2411524. That no. is on the mounting plate and stamped on the block. So, what year is it? I want to get the proper manual. Then the work will start to fix it. I will need your help with any info on this repair as we go. I dont want to be a bull in a china shop and just start tearing it apart. Any warnings?

 

[Grizzz]

Re: 115 HP No compression #3 cyl. Big fix? And what year is this Merc?

1968 Possibly?

 

[emckelvy]

Re: 115 HP No compression #3 cyl. Big fix? And what year is this Merc?

Well, it's not an 1150 with that serial number. Looks like Grizz is right, that ser. # range was found in '68 motors.

So, maybe you have a 1250 in disguise! Or a 100hp.

If you post a picture of the Starboard (starter side) side of the powerhead (with wraparound cowling removed), we can give you a pretty good idea of what block you have...........ed

 

[Buck Horn Deer Farm]

Re: 115 HP No compression #3 cyl. Big fix? And what year is this Merc?

Here is a pic of the starter side. What are you looking for to tell you the year?

 

[Faztbullet]

Re: 115 HP No compression #3 cyl. Big fix? And what year is this Merc?

Looks to be a 100hp with late model decals...be cheaper to find a running motor on craigslist and swap than repair. This is due to expense and scarcity of parts for that motor..(different ci)...