Mercury to Johnson

[DUNCANDAN]

Hi my question of the day is, does a 1985 Johnson 70hp have the same bolt pattern for the transom as a 1980 Mercury 150hp. I picked up an 16ft Sangster and it has the 150 on it! Boat is placarded with 85 Max. Besides I am partial to Johnson.

 

[roscoe]

Re: Mercury to Johnson

In 1980, Mercury was transitioning to the standard BIA bolt pattern, so you will have to measure.

The johnson is BIA standard.

It measures:

top holes, 12.875" part
bottom holes, 9.875" apart
top to bottom, 8"

All on center

 

[DUNCANDAN]

Re: Mercury to Johnson

Thanks Roscoe, Dan Johnson

 

[silverfox441]

Re: Mercury to Johnson

Welcome to the Sangster world! I got mine last year and i love it. Heavy but VERY solid. What year is yours cuz power rating might be in KW instead of HP. Mine says 65 KW wich about 90 HP give or take. I run a 115 Evinrude which was on it a the time of purchase. But i could argue that if i bough a new 90 hp motor, that would be rated at the prop and not at the crank, which was the case for older motor. So effectively, if you buy a new motor to match the max rating of a older boat, you are exceeding the said max rating. Geez, am i making sense here? Anyway, have fun and maybe i'll see you out there!

 

[79Merc80]

Re: Mercury to Johnson

Well, since the Merc 150 was a V-6, they had the standard bolt patern, It's the inline's that were still on the old patern. So, you should be ok.

Craig

 

[DUNCANDAN]

Re: Mercury to Johnson

Hi they are the same bolt pattern,Silverfox mine is a 1984 16', and is rated at 65kw. that is why I am putting on my 70hp Evinrude. I figure that Black Max would either scare me to death or tear the transom off.

 

[silverfox441]

Re: Mercury to Johnson

Cool! Mine is an '82. 115 HP is already plenty, i can't imagine 150... I mean i never use full throttle, i usually cruise between 4000 and 5000 rpm and i can get on plane with about 1/3 throttle, although very slowly.

Al.