Late 70’s Mercury 20 Hp manual

[tallcanadian]

Good day. I’m on the hunt for a good service manual for a 1978-79 Mercury 20hp outboard. Would anyone have a link or even a PDF I could purchase. I’m in Canada so finding one on eBay is very costly. These things are hard to come by. .

 

[Scott Danforth]

dont trust any PDF as the factory only did print. boatinfo is no longer around, so your only choice is to purchase a mercury manual from ebay or brunswick direct.

 

[tallcanadian]

dont trust any PDF as the factory only did print. boatinfo is no longer around, so your only choice is to purchase a mercury manual from ebay or brunswick direct.

Thanks. I’ve received a few PDF files that people have taken from the original manuals for other models of outboard. This particular one seems a bit harder to find, paper or PDF.

 

[merc850]

I bought a hard copy manual but it is for 1975 thru 1978 years (C-90-75512) so the next one is for 1979 - ? maybe this is your problem.

 

[tallcanadian]

I bought a hard copy manual but it is for 1975 thru 1978 years (C-90-75512) so the next one is for 1979 - ? maybe this is your problem.

Maybe. I have both a 1978 and a 1979 year models. They have subtle differences. I’m hoping to make one good motor from the two. There’s just a couple of things I’m not sure of, so I will need a bit of info from a manual.

 

[racerone]

What are you not sure of ?

 

[tallcanadian]

What are you not sure of ?

1: there is a pin that holds the shift handle in place. Not sure if it’s pressed in or if it’s a small Allen key. My eyes aren’t like they use to be.
2: my ‘78 has regular looking drive shaft with splines that go into the crankshaft. The lower unit is good. My ‘79 doesn’t have the spines, but a square end on it. There are no splines in the crank shaft.The lower unit on this one is bad. I want to swap these parts. Are they pressed on the crank? I guess it’s called a carrier assembly.

 

[racerone]

Sounds like some custom work ( square end ) was done.----All bets are off.

 

[tallcanadian]

Sounds like some custom work ( square end ) was done.----All bets are off.

Yes sir. I have to split the case. I’m glad I have a parts motor to use as practice. Lol.