1965 johnson 18 running poorly and leaking water? with video

altrocker1

Seaman Apprentice
Joined
Aug 27, 2011
Messages
40
hellllooo all....

so im having an issue with my 1965 johnson 18 and i wanted to get some opinions on it...its been running fine but when i took it out last night there seemed to be a lot more smoke than normal and i noticed it was not pumping water very well. when i opened the hood i noticed that water was running out underneath the head in the back. you cant see it in the video very well (very poor cell phone) but its right under the bottom cyl right under the head where it appears to be coming from. i did a compression check and it was about 110 in both cylinders so i dont have reason to believe that the head gasket is blown. but here is the awful video i took...

[video]http://s528.photobucket.com/albums/dd321/altrocker2/?action=view&current=0517122049.mp4[/video]

the only thing different about yesterday was that i changed the points and condensors because they were getting old. points were gapped correctly and spark seems to be good i haven't done a carb tune up on this outboard but it has always run well. is it possibly that my powerhead gasket is leaking somewhere causing water to get into the bottom cylinder? ive also noticed that it started running very poorly when i was running it in the tank today (last night i was on the river when it started acting up). it normally will let a lot of water out in the exhaust port but today in the tank it will only put water out when running at a higher rpm. i was only running it in short spurts since im a little worried about overheating. i changed spark plugs today as well but still with the same result. it always starts really well and today was no different...i also noticed that the bottom cowl has play in it. could this also be causing the water leak? either way, i feel like i may be pulling the powerhead to look. fortunately it only takes about 20 minutes on these old gals!
 

Daviet

Fleet Admiral
Joined
Sep 24, 2008
Messages
8,958
Re: 1965 johnson 18 running poorly and leaking water? with video

Can't see much on your video, but you see that round tube type thing cast into the cylinder head? It runs from the top of the head to the bottom. On the top of the cylinder head you will see a core plug in the top of it, there is supposed to be a core plug in the bottom also, maybe the lower one is missing and that's where your leak is.
 

oldybutagoody

Petty Officer 1st Class
Joined
Dec 30, 2011
Messages
207
Re: 1965 johnson 18 running poorly and leaking water? with video

I had a similar leak and found that the screws that go up from the bottom into the power head in the back had vibrated out. They were actually missing.
 

altrocker1

Seaman Apprentice
Joined
Aug 27, 2011
Messages
40
Re: 1965 johnson 18 running poorly and leaking water? with video

Can't see much on your video, but you see that round tube type thing cast into the cylinder head? It runs from the top of the head to the bottom. On the top of the cylinder head you will see a core plug in the top of it, there is supposed to be a core plug in the bottom also, maybe the lower one is missing and that's where your leak is.


actually you might be 100% right...that seems to be exactly where its coming out. is it possible to get a new one on without pulling the powerhead?
 
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