Flooding?

KyPoorBoy

Cadet
Joined
Jun 18, 2016
Messages
21
I have a similar problem with my Johnson 18hp. I think it's a 1960 model according to what the hood looks like on the parts list. When I prime it , gas will run out of the carb and then it won't start. I guess because it's flooding. Then I wait a few and it starts. Now , it barely runs at all and won't really reach high rpm's and when I disconnect the fuel line, the fuel runs out of the connection male end. How can I access the float and also I haven't noticed a valve on the cylinder head. Please be very specific with instructions as I am new to outboard motors. Thanks
 

jakedaawg

Rear Admiral
Joined
Jun 26, 2012
Messages
4,275
I have a similar problem with my Johnson 18hp. I think it's a 1960 model according to what the hood looks like on the parts list. When I prime it , gas will run out of the carb and then it won't start. I guess because it's flooding. Then I wait a few and it starts. Now , it barely runs at all and won't really reach high rpm's and when I disconnect the fuel line, the fuel runs out of the connection male end. How can I access the float and also I haven't noticed a valve on the cylinder head. Please be very specific with instructions as I am new to outboard motors. Thanks

It's a two stroke..no valve per say, at least not one opererated by a cam.

I think a manual may be in order here, some where online you can download those old ones I believe.
 

KyPoorBoy

Cadet
Joined
Jun 18, 2016
Messages
21
I have a manual on the way, they tell me the original factory service manuals for the particular model are the best So that's what I ordered. Is that true?
 

KyPoorBoy

Cadet
Joined
Jun 18, 2016
Messages
21
Thanks for the help. I thought that might be the problem and I wasn't thinking when.I asked , just wanted to confirm my suspicions.
Many Thanks
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,105
Those old motors had cork floats covered with shellac. They also had brass clamps on the floats that held the inlet needle valve. Check to make sure the shellac is still good, and that the brass clamp is not twisted. If the shellac is bad the float can absorb fuel. If the brass clamp is twisted, the inlet needle may not seat properly, Both of these conditions can cause the carb to flood..
 

KyPoorBoy

Cadet
Joined
Jun 18, 2016
Messages
21
Thanks everyone for sharing your knowledge.
I have cleaned the carburetor and.adjusted the float on my 1960 18HP Johnson Seahorse.
Now I am not getting full rpm at WOT. I have cleaned the points and reset the timing using a timing fixture. I checked the secondary coil and all seems ok except irregular to no power to the lower spark plug wire. Could it be the capacitor? That is all.That I didn't think of checking. How can I test a capacitor with a multi meter. And any other suggestions I would greatly appreciate. Thanks
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,468
Does spark jump a gap of 1/4" or more, yes or no ?------Likely you will need new coils on this motor.----Just picked up a nice 1969 model 6 HP and first thing I checked was the coils.------Both were cracked.
 

KyPoorBoy

Cadet
Joined
Jun 18, 2016
Messages
21
I just wanted to say Thank You to all of the good folks who are willing to share their experiences and knowledge of these old motors in order to keep them alive and to keep the tradition going. Especially the OMC motors which I have been a fan of for years but didn't have the time or money to play with until recently.
I am now happy to report that I have been able to rehab my latest project which is a 1960 Johnson Seahorse 18 hp. Since I cleaned the carburetor and now have a timing fixture, and more importantly, know how to use it. My motor runs like a brand new one. I am so excited and ready to start on my 1972 1972 25hp next..
I couldn't have done it without all the.advice I read in this and other forums and blogs and for.this I gratefully say Thank You.
 
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