water leak block/manifold

[Lee1]

Hi everyone, at the moment I have a four winns boat with a 4 cylinder omc inboard engine. I would apreciate any help or advice, there is a water leak coming form what seems to be the exhaust manifold. I have changed the manifold gasket and whilst doing so I didnt come across any cracks on manifold or block. The leak is coming from right under the manifold, does any body have any sugestions. Could it be the head gasket?

 

[Howard Sterndrive]

Re: water leak block/manifold

the block is cracked from freezing. If no water is getting in the oil, your options are:
-look for good used engine
-clean, dremel and epoxy the crack
-find a welder experienced in welding cast iron. They will want the engine removed from the boat though.

 

[Lee1]

Re: water leak block/manifold

Hi Howard thanks for the reply, another question can the boat still be used like this as we have been, we just bilge the water out?. Theres no water in the oil and the engine runs great no over heating or anything.
Another thing I changed the manifold gasket and then run it off a hose pipe on the drive, all is well. Then we went to sea about 45 minutes later and the engine started to play up. We tried to start it and it would turn over and start but when you leave go of the key the engine would cut out, I thought fuel delivery problem. Then when we got the boat home and back on the drive we thought try and start it see what happens, so we did and the engine run sweet as a nut, any thoughts flooded maybe?

 

[Howard Sterndrive]

Re: water leak block/manifold

yes, you can just use it as is, but the crack may worsen from vibration. Best to clean and epoxy at the very least. JB weld is one product many have used.
If you drill the ends of the crack (1/8 or 3/16" drill bit) before cleaning/epoxying, it relieves the stress to prevent further cracking.
If you buy a piece of stranded body repair fiberglass and work some glass strands into the JB as you mix it, it really helps.
One other method some engine shops use is called stitching. You can google block stitch repair for more info.
Sounds like you have an intermittent bad connection between the key switch "run" terminal and the ignition coil + terminal.
Works off the start terminal, but not the run terminal.
Could also be the ignition coil on it's way out.

 

[Lee1]

Re: water leak block/manifold

Thanks Howard for all your advice its helped me out alot. I look forward speaking to you in the future.