Year of Mercury motor

EHardgrave

Seaman
Joined
Mar 25, 2005
Messages
56
I was just given a mercury motor with blue decals on it. The S/N is 5343319 and it also says Thunderbolt ignition. I was wondering what year this is and any info on the ignition. Also any info about known issues etc. with this year motor.<br /><br />Thanks
 

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: Year of Mercury motor

7,5 5226935 - 5524659 1979 2 cyl... Don't know of any issues with the motor. Ignition is electronic. No points or condenser..
 

EHardgrave

Seaman
Joined
Mar 25, 2005
Messages
56
Re: Year of Mercury motor

Thanks for the info.<br />What is the mixture ratio for this motor? (oil to gas) Also it hasn't been started for over 5yrs. Where should I start to see if it is any good? I hate to turn it over to check compression if that might hurt something. But I don't want to spend much time or money on it if the compression is bad.
 

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: Year of Mercury motor

Oil mixture is 50:1 TCW 3 oil. Squirt a little of that oil into the cylinders through the spark plug holes and turn it over by hand 5 or 10 times to lubricate the cylinder walls. Best to Check the compression when the motor is warm, but if not possible, you can get an idea of how healthy it is when cold... See how that goes and let us know..
 

EHardgrave

Seaman
Joined
Mar 25, 2005
Messages
56
Re: Year of Mercury motor

Thanks. I will try that. Ant let you know.<br />Any opinions on using synthetic oil on a mtor of this age? I don't know any of the previous maintenance.
 

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: Year of Mercury motor

You know how those opinions on oil are? :) Theres been a ton of discussion on the forum about that subject and still no difinitive answer, except use what you are comfortable with. Personally, I would just stay with plain old TCW-3. Here's a little reading for your enjoyment, though...<br /><br /> D: What type oil should I use in my outboard?
 

EHardgrave

Seaman
Joined
Mar 25, 2005
Messages
56
Re: Year of Mercury motor

Wow, a lot there. Thanks<br />I wanted to find the weight of this motor too. Any idea why Mercury wants another digit in the s/n on there web site? Also I can't find the model either.
 

madmarlin

Seaman Apprentice
Joined
Nov 6, 2005
Messages
48
Re: Year of Mercury motor

Had same prob with Merc website doesn't like pre 1980 models apparantly ?
 

andrewkafp

Lieutenant Commander
Joined
Mar 15, 2003
Messages
1,668
Re: Year of Mercury motor

I would say close to 60lbs in USA language or 27kg over here.
 
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