TOPIC: merc 4.5 ls ?

Just bought a merc 4.5 long shaft motor that came with a sailboat.
Trying to figure out how old this motor is. Serial number from plate below motor port side is 6025858.
Boat is 1974. Motor looks newer but hard to tell. Seems to have had little use. To be honest I had an awful time with my merc 20 and want to know if I should just srap this and go buy a new one.
Thanks,
Paul

1982,,,,If you have deep pockets go ahead and buy a new one.Have you even started this or given it a chance,probably a great runner.Me, I would keep it , 1st thing throw a impellar and plug one her.

Excellent little motor.

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.It is rare that a motor needs to be thrown out.

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You need to find a place that will work on older motors !

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Most $100/HR shops do not have time for them as people with " old motors " do not generate easy revenue !!

Sorry to be so down on Merc. Most likely better built than the new ones..
Put fresh gas in it and it started right up on about the 7th pull, ran good. Almost fell off boat I was so surprised.....
But the water was not coming out when I shifted it into gear or run the rpm's up.
Shut it down and tried again with not luck.
Could have been due to the water movement in the barrel?? Not sure.
Will look into a new impeller. Would like to change it myself and will search out this site for help.
Mr 88, How did you get 1982 from the number? Look it up or unsramble the number?
thanks,
Paul

You must install a new impeller on any used motor that you buy.

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One nut ( 1/2" socket ) and one nut ( 9/16" wrench ) takes the lower unit off, water pump is right there.

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Mercury motor go by serial # to identify year.-Nothing you can " unscramble " to find the year.

And,...Your 4.5 might be one of the little Mercs that may have one of two impellers that are based on driveshaft diameter so be sure and check that before ordering in a new impeller.
Is the lil Merc getting hot to the touch?
Perhaps the tell-tale is simply plugged.
If it isn't getting hot - try blowing compressed air up the tell-tale exit port while it is running and see if perhaps it then starts to 'pee' a water stream out the tell-tail.
Thom

I did pee water in idle but when I put it in gear it stopped. Could have been due to cavitating in the barrel. I'll change the impeller before I start it again. I did not let it get hot.
Is the tell-tale the only water drain for the cooling system?
thanks,

no just a visual for you if clogged it will still cool.