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1968 Johnson 40 hp outboard need model # description

P

peteb

New member
"Through the process of elimin

"Through the process of elimination and due to a missing model/serial # id plate, I've narrowed down my 40 hp Johnson outboard motor to a 1968 model.

From my research I've discovered that there were 3 model lines offered for the 1968 40 hp model. The following model #s are listed for the 1968 motor but I'm not sure what each number stands for. Any assistance/explanation with the list below would be greatly appreciated:

1968 40hp Johnson outboard
RD-30 A,D, or S
RDL-30 A,D, or S
RDS-30 A,C, or D
RDSL-30 A,C,D, or S
RK-30 A,C, or D
RKL-30 A,C, or D
(my boat has electric start and a 2 lever Johnson Shipmaster control - rectangular shaped box)

Thanks!!!"
 
"Since it is an electric start

"Since it is an electric start, you can rule out the RD/RDL - those were rope start (only) versions.

So you either have an RDS or RK version - The "L" indicates "long shaft"

So an RDSL would be an electric start, long shaft

The RK version have "electric shift" as well. So an RK-30 would be an electric start/electric shift short shaft.

You didn't mention it having electric shift - so if it doesn't, then you have an RDS (L if it's long) model..."
 
"Could you please describe the

"Could you please describe the "electric shift" feature you mentioned. From what I've read, it has buttons that engauge forward and reverse rather than a lever. Is there more to it?

Also, since I have a Shipmaster (2 lever - no buttons) control, I would assume that it must be an RDS series. If that's true, how can I tell the difference between a long and short shaft model?

Thanks for you assistance - I'm getting close to figuring this one out!"
 
"The electric shift models als

"The electric shift models also had a generator that the other models did not, so under the "hood" if you there is a belt driven generator, it's an electric shift.

If you are using a tradition cable set-up for shifting/throttle, I believe your assumption would be right that you have an RDS model.

To determine if it is a short or long shaft. You measure from the top of the transom bracket (the bracket that hooks onto the boat with it in it's normal position) down to the the bottom of the cavitation plate on the lower unit.

A short shaft will be 16" (give or take an inch, for a 15" boat transom) and a long shaft about 21" (for a 20" transom).

I tried to doctor a pic a bit to illistrate what I'm saying..
83189.jpg
"
 
"No generator and a 16" sh

"No generator and a 16" shaft, it appears that I have a 1968 Johnson 40hp outboard, model # RDS-30 A,C, or D. Thanks again for your help Graham!"
 
"There you go, figured it out.

"There you go, figured it out. The letter on the end was just a "run" designator and has no bearing on the actual motor itself..."
 
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