Is it 2 stroke or 4 stroke

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jreid

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How can I tell if my boat motor is 2 stroke or 4 stroke it is a 1965 Johnson. And I'm new to boats so this might be a very simple question.
 

jreid

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Re: Is it 2 stroke or 4 stroke

Do you know what the mixture of gas and oil should be?
 

Daviet

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Re: Is it 2 stroke or 4 stroke

What's the horse power, should be 50:1 unless it's one of the small ones.
 

robert graham

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Re: Is it 2 stroke or 4 stroke

If it's a 1965, then it's a 2 stroke for sure and the gas/oil ratios may have been a bit richer(more oil per gallon of gas), better check on that and be sure. If in doubt then just run it richer. I'm thinking 32:1 or 25:1, but some of our "older motor experts" may know. Good Luck!
 

jtexas

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Re: Is it 2 stroke or 4 stroke

a 1973 oil ratio chart for older Johnsons.

Note where it specifies 50:1 only if Johnson brand oil is used, I think most would agree that any of today's TCW3 oils are as good or better.
 

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JasonAych

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Re: Is it 2 stroke or 4 stroke

First we need to know what model it is. Some had bushings in 65. That would be the deciding factor.
 

jreid

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Re: Is it 2 stroke or 4 stroke

1965 Johnson seahorse 40hp electric start is what I'm finding on the motor does that help?
 

jreid

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Re: Is it 2 stroke or 4 stroke

Does anyone have a manual on this type of motor for routine things?
 

jreid

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Re: Is it 2 stroke or 4 stroke

One more question is the whales tail necessary for the motor to work properly?
 

robert graham

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Re: Is it 2 stroke or 4 stroke

That whale-tail is just a gadget to help the boat get up on plane quicker and better. You can try it with it, then try without it, see which you like better.
 

54fleetwin

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Re: Is it 2 stroke or 4 stroke

First off,
Get rid of the engine and get a new one.
The engine is old and will need work done to it.

If you have to ask whether its a 2 or 4 stroke, then you have know idea what the difference is and you should not be allowed to pick up a wrench.

Just get something newer that doesn't need work and go enjoy the water.

EDIT: This type of post and the reactions it causes are contributing to the general nastiness we are seeing lately. Please knock it off.
 
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Shrike

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Re: Is it 2 stroke or 4 stroke

First off,
Get rid of the engine and get a new one.
The engine is old and will need work done to it.

If you have to ask whether its a 2 or 4 stroke, then you have know idea what the difference is and you should not be allowed to pick up a wrench.

Just get something newer that doesn't need work and go enjoy the water.

Wow!
 

JasonAych

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Re: Is it 2 stroke or 4 stroke

Wow. Some pretty big assumptions and judgment made there 54Fleetwin.

The guy has not asked how to overhaul his engine. He wants to know if he needs to add 2 stroke and how much. At least he didn't just run it without asking.

Does anybody have a parts diagram for his engine? If it has all needle bearings then 50:1 should be fine, if there are any bushings, even in the wrist pins or just at the bottom of the crankshaft, you should run like 24:1 or even 20:1. I have seen 3 mid 50's 15hp Evinrudes in a row recently with bad wrist pins and bushings.
 

54fleetwin

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Re: Is it 2 stroke or 4 stroke

Sorry bad day
Still if you have to ask that question, should you really be wrenching on an old motor?
 

Daviet

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Re: Is it 2 stroke or 4 stroke

I kinda think it is a good way to learn, get an old engine and fix it up asking questions along the way.
 

Vic.S

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Re: Is it 2 stroke or 4 stroke

Does anybody have a parts diagram for his engine? If it has all needle bearings then 50:1 should be fine, if there are any bushings, even in the wrist pins or just at the bottom of the crankshaft, you should run like 24:1 or even 20:1.

The parts diagrams are HERE

The model on question appears to have needle roller bearings throughout so from that point of view a 50:1 fuel mix will be just fine.
 

jtexas

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Re: Is it 2 stroke or 4 stroke

...
Still if you have to ask that question, should you really be wrenching on an old motor?

As a general rule, on this forum (unlike some other forums I've visited) when someone asks a question that indicates a lack of experience and/or knowlege, we try to give them the benefit of our experience and/or knowlege. Instead of advising them to give up before they even started, we generally attempt to provide help on a level they can understand. Probably because none of us are so old that we can't remember the first motor we ever worked on (although some of us are getting close).

Whenever you encounter a question that might require more time than you have available, feel free to pass on it, usually someone else will come along with an answer.

thanks,
 
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