cant find the leak

wilddonkey75

Cadet
Joined
Jun 30, 2010
Messages
7
I have a 1985 100hp johnson that is getting water in a cylinder. I had the head resurfaced and replaced head gasket but still leaks. Then I replaced the inner and outer exhaust gaskets and checked the plate for cracks but found none. I am still getting water in the cylinder. What is can it be? Can water get it there if the head cover gasket is leaking? What are all the ways it could get in there?
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,931
Re: cant find the leak

Which cylinder? Has motor overheated before? Is it a salt/brackish water motor?
 

wilddonkey75

Cadet
Joined
Jun 30, 2010
Messages
7
Re: cant find the leak

I changed the exhaust gaskets and checked the plate for cracks but didnt find any. It hasnt over heated since ive had it but ive only had it out 3 times and the first time it ran great. The next couple times is when it started leaking. It is ran in fresh water only and its the left bottom cylinder if your at the rear looking at the engine thats leaking.
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: cant find the leak

Sounds like you have taken care of the head gasket. Exhaust water leaks tend to affect the lower cylinders, as in your case. You indicated that you have replaced both exhaust gaskets-normally the proper fix. If those gaskets did not cure the problem, you may have a problem with the inner exhaust cover leaking-a fairly rare situation. I have seen them suffer from casting prorosity. A good way to check is to lay the inner exhaust cover flat and layer some water on it, then check for leaks on the other side. Or, you can hold the cover up to a bright light and observe to see if any light shines through the cover. The cooling system will develop enough pressure to force significant water through even a pinhole and allow water into the exhaust chest. Also, you should retorque both the heads and the exhaust cover(s) after the engine goes through a 2 or 3 heat/cool cycles.
 

wilddonkey75

Cadet
Joined
Jun 30, 2010
Messages
7
Re: cant find the leak

Thanks for the info. So chances are that I just missed something? Im new to boat motors so there is no other way for water to get in the cylinder? I'm about to go crazy with this thing. I'll order new gaskets again and check everything very good for any leaks. Thanks again for the help, love this site and I'll give a update after i get the new gaskets.
 
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