1953 Johnson Seahorse 3hp

bluevanu

Cadet
Joined
Mar 1, 2011
Messages
7
I have a Johnson JW-10 that I recently bought. The fuel valve is open, the tank vent is open, the motor sounds great and pushes the heck outta my 12ft. flat bottom boat. Problem is it only runs about 10 seconds and only if the choke is engaged. Kill the choke and the motor dies immediately. Leave it and it runs a few seconds and then dies.
 

1946Zephyr

Vice Admiral
Joined
Oct 21, 2008
Messages
5,556
Re: 1953 Johnson Seahorse 3hp

I would totally clean out the fuel line and make sure the fuel flows freely. These often clog up over time and fuel flow gets restricted. Also check your needle jets too. High speed should be about 1/2 to 3/4 of a turn out from lightly seated and low speed should be 1 1/4 to 1 1/2 turns out. You may need to rebuilt the carb too, but I would start with these two remedies first.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
Re: 1953 Johnson Seahorse 3hp

Check that sintered fuel filter in the tank. They get partially plugged and fuel doesn't flow fast enough to keep it running. They are virtually impossible to clean but some people claim the clean them (?) Anyhow, you are supposed to simply replace it. I unsolder the sintered filter and toss it and replace it with brass filter screen.
 

bluevanu

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Joined
Mar 1, 2011
Messages
7
Re: 1953 Johnson Seahorse 3hp

Thanks for the reply. I checked the fuel line, fuel tank, and took the carb off and checked it. All were clean as a whistle. The man I got it from said that he just had it reworked and after looking, I believe him for the most part. I checked the spark plugs and neither would fire when pulled out and starter cord was being pulled. But the plugs look to be in good shape. And they were firing just a few hours ago, just wouldn't stay running. Could something else in the ignition system be causing my problem?
 

bluevanu

Cadet
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Mar 1, 2011
Messages
7
Re: 1953 Johnson Seahorse 3hp

I have checked it and it looks as if someone has drilled a hole in it. I think I will try to replace it with that brass filter screen you mentioned.
 

kbait

Commander
Joined
Nov 13, 2007
Messages
2,446
Re: 1953 Johnson Seahorse 3hp

Some gunk probably got through the hole in the filter and clogged up the carb. That would answer the running briefly on choke issue, but not the no spark??
 

bluevanu

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Mar 1, 2011
Messages
7
Re: 1953 Johnson Seahorse 3hp

Well, not sure about the no spark issue. Just got done cleaning out the fuel shut off valve. Was clogged extremely bad. I don't see how any gas got through. Got it back together and it cranked and ran a good 20 mins or so before I shut it off.
 

tmcalavy

Rear Admiral
Joined
Aug 29, 2001
Messages
4,005
Re: 1953 Johnson Seahorse 3hp

compression check, wire check, clean the fuel system...tuneup on the way
 

bluevanu

Cadet
Joined
Mar 1, 2011
Messages
7
Re: 1953 Johnson Seahorse 3hp

Thanks very much for the suggestions. I got it running but now I have pulled the pull cord out. Went to put it back in and the spring unwound on me. So, the question is, how does it go back in. I put it back the best I could figure it should go but something still isn't right. It won't pull.
 

bluevanu

Cadet
Joined
Mar 1, 2011
Messages
7
Re: 1953 Johnson Seahorse 3hp

Got it! Its up and running great! Thanks for all the help.
 
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