Re: water coming from spark plug 165hp
 

It is most likely your exhaust manifolds. They have a water jacket in them that will corrode and dump water into the cylinders. My bet is that is where the problem is. Take the manifold off and have a look.

Re: water coming from spark plug 165hp
 

Been there done that! Head has to be replaced!! Good Luck!

I changed it the first time, and I converted the 2nd time!!

Re: water coming from spark plug 165hp
 

boy, hope you werent lookin for an ez fix! good luck

Re: water coming from spark plug 165hp
 

Mine was a 1975 so it was all the same you have. and the same plug!!

I was able to find a good car motor and used the head from that, I got the motor for $100, I ended up using the head and the oil pan.

Manfold went right after that!!

The second time it went was the #2 plug, don't know what happened, Gasket, rust, crack??

All I know was that it was going to be the last time!! I had it with that thing! Bracket and O/B and have never looked back! and it was easier to convert the monkey around with that motor all the time!

Re: water coming from spark plug 165hp
 

I'm more inclined to agree with frayed about the exhaust manifold being rotted and needing replaceing, it is the most likely culprit.
At least you got to take it off first to get to the head and gasket, you'll see then.

Re: water coming from spark plug 165hp
 

Where are you located? I have a spare motor from my 73 sitting in the barn and two lower units. One of the lower units is still in one boat and the other was rebuilt with not alot of time on it.

Re: water coming from spark plug 165hp
 

Flatliner didn't mention whether or not he had fresh water cooling. If so, does he need a marine head gasket?

Re: water coming from spark plug 165hp
 

Did they have them that year? I guess there is no reason not to.

Re: water coming from spark plug 165hp
 

Raw water cooled!! all the old ones were unless someone added it later.

I have done this hole repair!! Head, then $500 for new manfold and riser, more cash for the gasket set, more for the exhust bellows that will surly be junk by the time he gets it off?

And the new manfolds come with new hose config to help with hot spots.

Re: water coming from spark plug 165hp
 

thanks for the help i brought my mechanic there and his diagnosis was a cracked piston head does tht sound about right.