1978 Mercury 70hp Worth Messing With?

[Berdink]

Assuming it has good compression. Assuming it runs and has a good lower unit.
Is it worth keeping?
It looks like parts are a little hard to come by than my Johnson.

 

[Berdink]

 

[Mc Tool]

Well , if it has all the things you assume it has , wtf not , I mean it looks to be in reasonable nick . If it goes ok and doesnt have any death rattles .
1978 doesnt necessarily mean its got a lot of wear on it ...might be a tidy old donkey . After that I guess it comes down to what you have to pay to get it .

 

[Chris1956]

Check the engine wiring harness, especially the quick disconnect plug. Look for insulation that is falling off.

I would expect ign and carb parts to be avail, as well as normal maintenance stuff.

 

[racerone]

Not a robust lower unit for a 70 HP.----And 2 carburetors for 3 cylinders.----Not on my list of favorite motors.

 

[Texasmark]

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Follow the fuel input hose to the fuel pump attachment point.....look at the hose below it.....I see what looks like that connection is bad.....replacing the hoses is a good place to start. Wiring seems to be in good shape.

Usually new kits in the carbs with a thorough internal cleaning with good compressed air blow out when finished cleaning......water pump maintenance, may just need an impeller (would replace anyway) if the pump housing isn't all scarred up internally from impeller wearing on the surface where you would need a new pump.

If you get to the point of starting the engine (with a fresh, fully charged battery with good clean (internal) connections on both ends of the power cables) and something doesn't respond/perform to expectations, I'd get a wrench on every electrical connection that isn't covered with a rubber cap and back the locking device out a little, move the wire/lug back and forth a few times and secure the attachment. Sometimes corrosion gets in there and messes up the conductivity of the connection.

 

[Berdink]

Yes, all the fuel lines need replacing. I won't even attempt to turn it over without replacing all of them - they are dried stiff.
And yes, definitely will replace the impeller.
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It was given to me by an older lady I work with who recently lost her husband. She knows I like boats and fishing and told me to just come and get it.
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From my research, it's far from having the support of a Johnson/Evinrude.
So I was wondering if it was even worth attempting to get it usable.
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She said her husband had it running last year.
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I'll first remove all the fuel lines, then do a compression test and check the spark with a 3/8" gap spark tester today.