Kill Cord for an old Johnson

Sandro1936

Recruit
Joined
Jan 17, 2010
Messages
5
Hi there,

My Drascombe Dabber Giulia is driven by a 2 stroke Johnson 4hp of 1984 that does not feature a kill cord switch.
As I often sail/motor single handed, would it happen to me an unintentional fall over the side, it would not be a pleasant one the sight from astern of her chugging merrily away leaving her master bobbing in the wake.
I considered a few options, none of which looks practically viable:
1) Leading out of the flywheel plate two wires paralleled to the points and using a modern kill switch and cord by the trade.
2) A loaded spring, triggered by the kill cord, pushing the throttle control all the way down.
3) A rubber flap shutting the air intake.
Is there anybody that has confronted the problem and can suggest a solution?
Of course I wear a harness when single handed but neither being towed in the water is a pleasant experience, let alone the propellor danger.
I am posting this question both on the Practical Boat Owner and on the iboat/Johnson & Evinrude Outboard forums. I expect that multiple posting is not against forum etiquette. It?s just to widen the search.

Sandro
 

Vic.S

Rear Admiral
Joined
May 4, 2004
Messages
4,720
Re: Kill Cord for an old Johnson

I reckon a modern kill switch and cord connected as you suggest. But I said that on PBO's Reader to Reader forum.

Nobody here knows what a Drascombe Dabber is, that's the trouble.

Should post a picture

drascombedabber.jpg



Well that's bumped the post up
 

samo_ott

Vice Admiral
Joined
Jun 18, 2006
Messages
5,125
Re: Kill Cord for an old Johnson

Hook up a kill switch to the points. Is the easiest, most common method used. I would not consider any other method.
 

Sandro1936

Recruit
Joined
Jan 17, 2010
Messages
5
Re: Kill Cord for an old Johnson

Nice picture, VicS! Thank you.
But the boat herself is not involved in the search.
Is there someone that can tell me the exact size of the thread of the three holes on top the flywheel of a Johnson 4hp J4BR-CRM of 1984?
 

samo_ott

Vice Admiral
Joined
Jun 18, 2006
Messages
5,125
Re: Kill Cord for an old Johnson

The older ones are 1/4" x 20 pitch thread. I would assume the same for the newer ones... And you should get grade 8 hardened bolts.
 

Vic.S

Rear Admiral
Joined
May 4, 2004
Messages
4,720
Re: Kill Cord for an old Johnson

and 1/4" by 20 tpi is a coarse thread ie UNC not UNF.

It is the same pitch as Whitworth but as you will know the thread form is slightly different. For something like this I would not risk using Whitworth esp because whitworth bolts are not usually high tensile.

FWIW the holes in my '84 6hp flywheel are 1/4" by 20 tpi .. I just tried a 1/4" Whit bolt in them!
 

Sandro1936

Recruit
Joined
Jan 17, 2010
Messages
5
Re: Kill Cord for an old Johnson

Samo ott: thank you
VicS: thank you. Seeyou on PBO Reader to Reader.
 
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