Johnson K35 Runs! – How to keep it cool?

[John Gragg]

Good news. The K35 actually runs and runs pretty well.

I couldn’t let it go longer than about 4 or 5 seconds as I’m waiting on shear pins for the prop AND I have no idea how I can hook something up to mimic the prop-wash that would normally feed the cool water to the motor.

Has anyone seen anything they can share on how to get water to this pumpless motor?

Any help or advice is greatly appreciated!

Thank you and Stay well.

John

John Gragg
RIverside, CA

Just starting in the hobby, please be patient.

48 Sea King 5hp GG9014A. Sold
49 Sea King 5hp GG9014A
48 Johnson TD20. Sold
49 Johnson TD20. Sold
54 Johnson QD15. Sold
55 Johnson CD12. Sold
57 Johnson RJE-19M
57 Johnson RDE-19

[Waunnaboat]

Testing it in a bag tank or on a lake/pond/river would really be the only practical way to test it for longer periods.  You should be fine running for at least 20-30 seconds before shutting it off, especially if it is at low speed and it is cold out.  The reason that you cant run motors with rubber impellers long is because the impeller will be damaged due to friction and heat, but with motors such as this that is not so much of a concern as the engine actually overheating.  As long as the motor does not get hot enough that the metal of the cylinders/pistons starts to expand with heat, running it for more than 30 seconds but less than a minute at slow-ish speeds should not cause any major issues Otherwise, taking the prop off and trying to spray a hose in the water scoop might work, but it would be easier to test on a lake at that point, even if the weather outside is as frigid as it is in Wisconsin right now.

"Outboards seem to multiply exponentially..........I find that for every finished project, there are two more waiting to be completed."

1 user thanked author for this post.

John Gragg

[Tubs]

If you want to go to all the trouble, remove the water lines on the top of the cylinders. Don’t attempt to turn the fittings in the cylinder. 95 % chance they will snap off!!! A 1/4″ union would have  2 compression nuts and sleeves. Connect  some 1/4″ plastic hose and run it so its away from the exhaust and flywheel. You could connect both hoses to a compression T so there would only have 1 line to deal with.  I have this brass hose nozzle that I slip hose combinations of hoses on. They fit tight enough they wont blow apart if I have the pressure right. This works for me because its stuff I have, and I’m familiar with it. What do you have experience with that you could adapt for cooling the cylinders.  Think about it. 

 

 

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

2 users thanked author for this post.

John Gragg, seakaye12

[John Gragg]

Waunnaboat wrote:

Testing it in a bag tank or on a lake/pond/river would really be the only practical way to test it for longer periods.  You should be fine running for at least 20-30 seconds before shutting it off, especially if it is at low speed and it is cold out.  The reason that you cant run motors with rubber impellers long is because the impeller will be damaged due to friction and heat, but with motors such as this that is not so much of a concern as the engine actually overheating.  As long as the motor does not get hot enough that the metal of the cylinders/pistons starts to expand with heat, running it for more than 30 seconds but less than a minute at slow-ish speeds should not cause any major issues Otherwise, taking the prop off and trying to spray a hose in the water scoop might work, but it would be easier to test on a lake at that point, even if the weather outside is as frigid as it is in Wisconsin right now.

So Calif boy here… only boat I have access to is my I/O…lol

Thank you tho’

John Gragg
RIverside, CA

Just starting in the hobby, please be patient.

48 Sea King 5hp GG9014A. Sold
49 Sea King 5hp GG9014A
48 Johnson TD20. Sold
49 Johnson TD20. Sold
54 Johnson QD15. Sold
55 Johnson CD12. Sold
57 Johnson RJE-19M
57 Johnson RDE-19

[John Gragg]

Tubs wrote:

If you want to go to all the trouble, remove the water lines on the top of the cylinders. Don’t attempt to turn the fittings in the cylinder. 95 % chance they will snap off!!! A 1/4″ union would have  2 compression nuts and sleeves. Connect  some 1/4″ plastic hose and run it so its away from the exhaust and flywheel. You could connect both hoses to a compression T so there would only have 1 line to deal with.  I have this brass hose nozzle that I slip hose combinations of hoses on. They fit tight enough they wont blow apart if I have the pressure right. This works for me because its stuff I have, and I’m familiar with it. What do you have experience with that you could adapt for cooling the cylinders.  Think about it. 

 

 

Motivation received. Time to put on my McGyver hat and make something happen! Thx!

John Gragg
RIverside, CA

Just starting in the hobby, please be patient.

48 Sea King 5hp GG9014A. Sold
49 Sea King 5hp GG9014A
48 Johnson TD20. Sold
49 Johnson TD20. Sold
54 Johnson QD15. Sold
55 Johnson CD12. Sold
57 Johnson RJE-19M
57 Johnson RDE-19

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