1967 Johnson, Prop Swap. Help!

JustWarminUp

Seaman
Joined
May 11, 2020
Messages
62
Hey!

I have a 1967 60hp Super SeaHorse Electric.
(VXL-13A)

Runs like a beauty, but my prop is just chewed up and worn as the boat was. (Boat turned out great!! Cannot wait to post a picture!!) I have Searched and searched hours upon hours, even parts for part numbers and even then I cannot find my specific Motor in part catalogs.

Could anyone help me understand how I would go about Swapping the prop on this to something more Modern?
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,033
Your location ??----What do you mean by " something more modern "-------You could try adapting a 60 HP electric shift with through the hub exhaust I suppose.-----You have searched for hrs and hrs ??----Try searching for a 75 HP model 1965 as they use the same props !!!
 

JustWarminUp

Seaman
Joined
May 11, 2020
Messages
62
Sweet! I will dig right into that.

Might pick that one up Texasmark Posted.
Thanks!

I'm up in Minnesota, I dont know much of boat motors. But been on cars my whole life, so I'll get it one way or another.

for more "Modern" i was thinking a stainless steel due to rocky shores, rivers, ect.
maybe even a 4 blade prop for a smoother ride.

Maybe more pitch, I Do not have a Tach so I dont know where the RPMs sit, but I would not be opposed to taking them down 200-400. Due to the age of the motor. (Maybe a walk through to install one on this motor and I would surely grab one off the shelf and slap it in the boat real quick)

I'm not after top speed or anything crazy, just a tough prop and a smooth ride along the way.

but again I am not boat motor master so thus why I have come to the masters :D
​​​​​​​
 

JimS123

Fleet Admiral
Joined
Jul 27, 2007
Messages
7,952
Michigan Wheel sells props for that motor. They only list two - an 11 and a 12 pitch. Both are aluminum. No other types available. One is for a 16-17' boat and the other 14-16'. For motors that old that's the closest they categorize them, because back then tachs were not considered to be needed.

You didn't tell us what boat it will be on. Before you go off and buy the ebay model, better find out what pitch it is.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
12,944
Even when that engine was in its prime, OMC only offered 6 props for it.
Most yrs it was shipped from the Factory with the 9 1/2” X 10"
You can find the props on ebay,

#378039 10" X 12"
#377978 10" X 11"
#378040 10 1/4" X 10"
#379448 10" X 9 1/4" small hub prop, uses a smaller drive pin and prop nut
#593437 9 1/2" X 10"

WOT range for that engine, is 4000 - 5000 rpm
I doubt there are SS props in existence for that motor, except maybe a couple custom made for Racing.
There were some Bronze ones made by Michigan in the 60s


Edit: In 1967 the 60 was offered with 2 gearcases, the 'Hi Speed', which used the props above and a Heavy Duty version which was from the 1958 - 59 50hp and used a larger prop. You most likely have the Hi-Speed case
 
Last edited:

JimS123

Fleet Admiral
Joined
Jul 27, 2007
Messages
7,952
Even when that engine was in its prime, OMC only offered 6 props for it.
Most yrs it was shipped from the Factory with the 9 1/2” X 10"
You can find the props on ebay,

#378039 10" X 12"
#377978 10" X 11"
#378040 10 1/4" X 10"
#379448 10" X 9 1/4" small hub prop, uses a smaller drive pin and prop nut
#593437 9 1/2" X 10"

WOT range for that engine, is 4000 - 5000 rpm
I doubt there are SS props in existence for that motor, except maybe a couple custom made for Racing.
There were some Bronze ones made by Michigan in the 60s


Edit: In 1967 the 60 was offered with 2 gearcases, the 'Hi Speed', which used the props above and a Heavy Duty version which was from the 1958 - 59 50hp and used a larger prop. You most likely have the Hi-Speed case

Now that's good info!
 

JustWarminUp

Seaman
Joined
May 11, 2020
Messages
62
Alrighty!! Yes!!!! So excited to find someone that knows what I have on hand, cause I don't lol!!

I hate so sound like a fool, but how can I tell if it's High speed model? I'm totally invested cause this things a beast and I dont want to get rid of it!! Reminds me of my grandfather lol.

The boat itself is a 1976 Trihull Forester 15'.

Redid the entire Hull with a Blue Above Grey on White. It turned out AMAZING Due to the professional neighbor coming over and slapping some tape lines down for me after the initial white coating. (Gel coat was an option but this made colors and lines easier, used Marine grade paint)


side note, if anyone can tell me which wire I would need to tap into to attach a Tach I would do that immediately before I even hit the water again.


What is the difference between bronze and Aluminum by the way???


Thank you all!!!
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,033
The heavy duty gearcase ( 1958 / 59 fat fifty ) splits along the propshaft c/line with many screws.-----The high speed gearcase had a pointy nose.------It is referred to be a " high speed " gearcase because the prop spins fast.----It is not a fast motor or racing model.
 

JimS123

Fleet Admiral
Joined
Jul 27, 2007
Messages
7,952
A "tiny tach" will attach to a spark plug wire and is a simple installation.

Your motor is a classic (almost antique) so it probably won't matter which lower unit you have because you probably won't find a specific model.

Back in the golden age of outboards most props were a 3 blade aluminum because they were inexpensive. But they were also brittle so hit a rock and you need repair. We had a aluminum "power prop" for skiing. When we wanted to go real fast we switched to a 2 blade bronze "speed" prop.

A good percentage of the early motor props were bronze (or even brass) because they were salt water safe, provided less galvanic corrosion and didn't grow barnacles. If you bent one it was easier to merely straighten it out. Aluminum won't bend back and thus must have a new tip welded on.

We're talking outboards here - most moored straight inboards use bronze props.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
12,944
If on the slight chance your motor has the Heavy Duty case, your choice of props is even more limited. As far as I know only two were made by OMC a 13" X 13", and a 12" X 14"

We had a 1965 90hp, and it had the "Hi Speed' gearcase, we had 3 props, the 10 X 11, the 10 X 9 1/4, and the 9 1/2 X 10. They were all within 1 mph of each other, with the 11" being 400 rpm lower than the other 2, and the 10 X 9 1/4 having the best Hole Shot. The 9 1/2 X 10 had the same WOT rpm as the 10 X 9 1/4, but was more leisurely on Acceleration
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
12,944
#379448 10" X 9 1/4" small hub prop, uses a smaller drive pin and prop nut

#379448 was superseded with #379260
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
Michigan Wheel sells props for that motor. They only list two - an 11 and a 12 pitch. Both are aluminum. No other types available. One is for a 16-17' boat and the other 14-16'. For motors that old that's the closest they categorize them, because back then tachs were not considered to be needed.

You didn't tell us what boat it will be on. Before you go off and buy the ebay model, better find out what pitch it is.

I wouldn't loose any sleep over a 1" difference in the prop, and if running a chewed up prop, certainly change is in order. On the Fat 50 and the cubes and OMC's love of big blocks at low rpms, I wouldn't worry about lugging. like stated, never saw or heard of a tach back in those days in my lower echelon of the boating world.

Michigan wheel built bronze props back then and I had a 3 blade for my 25 hp Wizard. I don't remember the pitch but do recall calling it my "power prop" for water skiing. I got the idea because OMC was running 3 blade props on their engines of the day and they were pulling circles around me. Don't recall much difference between running that and the 2 blade alum. that came with the engine when I bought it new from a Western Auto Store for $400 of my hard earned money as a teen. I mean when you are a teenager, you really haven't been around long enough to figure out how the world turns.
 

JustWarminUp

Seaman
Joined
May 11, 2020
Messages
62
Alrighty! So I spent some time and found the following 4 props new condition

$55. #378039 10" X 12"
$70. #377978 10" X 11"
$70. #378040 10 1/4" X 10"
$70. #593437 9 1/2" X 10"

price wise I want to pull on the 10" x 12" (less rpm more propulsion right?)
I dont plan on WOT right off the bat ever, will have little ones on board, would this be a smooth accel?

Also

Do I need to worry about that being too much load on the motor itself and rpm drop for its age and Longevtity wise at WOT?



Price aside, which prop would you guys get?



Do I need anything for when I swap the prop? New deals, new pins, new anything other then a cotter key for the cone.





If anyone want to double check my searches.


10" X 12"
https://www.ebay.com/itm/OMC-Propeller-378039-10-X-12/164146205851?epid=1925248778&hash=item2637e054 9b:g:NmEAAOSwQahehKwR

10" X 11"
https://www.ebay.com/itm/MICHIGAN-W...9253387?hash=item1f0941308b:g:umEAAOSw0TheF4D o

10-1/4" X 10"
https://www.ebay.com/itm/MICHIGAN-W...8316790?hash=item1f0932e5f6:g:RKIAAOSwR8heF2z j

9-1/2" X 10"
https://www.ebay.com/itm/MICHIGAN-W...0200441?hash=item1f094fa3f9:g:9Q0AAOSwUEFeGLF p
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
12,944
Odds are you will end up using the 9 1/2 x 10, possibly the 10’1/4 x 10, as you have the lowest HP of all the engines that use those props. I think the 10 x 9 1/4, would be the best choice, if you can find one

Your engine while having a large displacement for its HP rating, is still at risk to Damage from over propping.

You mentioned a Prop Nut(you called it Cone), which one is it? The big one is about 2 1/2 inches, the small one is about 1 1/2”. Either will fit/work with all the props, along with the short Drive Pin, but only the small one will fit the Small Hub 10 x 9 1/4

I haven’t seen you mention what kind of boat you are putting this on

edit; unless your boat is a 10 ft racing hull, I doubt it would get on plane with the 12”
 
Last edited:

JimS123

Fleet Admiral
Joined
Jul 27, 2007
Messages
7,952
I don't know what boat you have. If its a "regular" runabout I would be inclined to go with the 11". But really its a crap shoot. Tach it out and your second choice will be spot on.

You need a brass shear pin for the prop, a SS cotter pin for the cone, and of course a cone.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,033
Agreed ----The drive pin is stainless.-----Few folks are prepared to hang over the back of a boat to change brass shear pins these days.
 

JimS123

Fleet Admiral
Joined
Jul 27, 2007
Messages
7,952
I stand corrected. The only shear pins I ever changed were brass, albeit they were smaller motors.

Regardless, I was never agile enough (or tall enough) to hang over the back. It always required paddling to shallow water and jumping out.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,033
That is the very reason they went steel drive pins and Mercury to the splined " shearproof drive "------Not cheaper or better at all.-----A lot more expensive / damaged props !! --Just more convenient for the consumer.
 
Top