cooling water on top of the head

[sailingdon]

new to the forum, not new to Moyer Marine. my A4 is original in my 1973 C&C 27. no major engine work for at least 15 years (my ownership).
on first start this Spring, getting water on top of head, dribbles into spark plug cavity, and bubbles into steam. by looks of rust in spark plug cavity, this may have been going on for awhile. engine is raw water cooled.
wondering if i should attempt to tighten the head bolts, or if there is a compound that would stop the leaking temporarily. or if there is any other tricks that put off removing the head.
thanks for all replies.

[Al Schober]

Recommend you try to identify the source of the water.
Since I'm guessing, first on the list would be the thermostat housing. A close second would be the cooling hoses & fittings. Also check for any other hoses running over the engine - I've seen 'engine leaks' that weren't due to the engine at all.

[Dave Neptune]

Welcome and ID first!!

First welcome to the Afourian Forum. Second what Al said and don't touch the head bolts yet!!!!! The t'stat housing can be problimatic and the hoses and/or fittings too.

Dave Neptune

[Mo]

+1 what Dave said.

[sailingdon]

places to look

Thanks Afourians, now i have a work plan to resolve this malady of mine.

[Ajax]

I'm betting that the water is running downhill into the plug cavity from the thermostat housing.

Check your thermostat gasket while the engine is running. Shine a flashlight on the backside of the housing. I'll bet the gasket is weeping. This happened to me.

[Bold Rascal]

Same here!

Welcome to the forum and for sure let us know what you determine.

I occasionally find a little pool of water around the spark plug on No1 cylinder. My suspicion is that it's not from a leaking hose or the thermostat housing but rather from rain water. My no1 cylinder is directly beneath the companionway access sill and I know it's not water tight.

[CalebD]

new to the forum, not new to Moyer Marine. my A4 is original in my 1973 C&C 27. no major engine work for at least 15 years (my ownership).
on first start this Spring, getting water on top of head, dribbles into spark plug cavity, and bubbles into steam. by looks of rust in spark plug cavity, this may have been going on for awhile. engine is raw water cooled.
wondering if i should attempt to tighten the head bolts, or if there is a compound that would stop the leaking temporarily. or if there is any other tricks that put off removing the head.
thanks for all replies.

Welcome to the MM forums.

We had what sounds like a similar issue last year. Ultimately we found that replacing the head gasket was necessary.

We still get a little water emerging on top of the head from one of the bolts that hold the alternator bracket to the head.

I posted a thread here about it at that time and if I recall it was suggested that I get the Permatex #3 gasket compound and apply it around the problem stud(s) below the head. We did not do this when we replaced the head gasket but I did buy the Permatex #3 so I can try this when I next take off the head and replace the gaskets, again. I hope to get to this soon.
Here is that thread:

http://www.moyermarine.com/forums/showthread.php?t=6644

If that does not work then I guess I will be looking to replace the head with a new/used one.

[sglazebrook]

I had this problem when I first got my A4. Turned out to be an invisible crack in the head at the alternator mounting bracket studs - just big enough to let water escape when under load but not at idle. Tried the new gasket way and sealing the stud holes but that only slowed the flow from a trickle to a drop.

Hopefully you wil have better luck than me!

[sailingdon]

update on cooling water leak

As best i can tell from today's observation, i have water coming up from the spark plug hole. there is a lot (ounces) at the second cylinder, and a lesser amount at the next cylinder, going from front to back of engine. it seems to bubble up and turn to steam, and those plugs are very rusty.
Next trip to the boat, I plan to pull the plugs, and check the color of the electrode. i read or heard somewhere that if the electrode is white, it would indicate a blown head gasket.
any more theories i should consider?
thanks, Don

[sailingdon]

update to Water leak on top of the head

Upon removing the alternator bracket ( which included removing a head bolt as the nut would not come loose), then starting the engine, I found several pin holes on the top of the head. They were not on the smooth, flat surface that supports the alt. bracket, but that bracket does hide a little more of the head, maybe half inch. In the half inch space is where those little holes are. they are now covered by a small amount of J-B Weld epoxy. This fix tested good, so I did more wire brushing to clean the entire head surface and painted the engine.
I have sailed 4 times since then, where the engine ran for 30-60 minutes, and still not a drop of water on the head.
Now i hope it stays that way till the end of this season. Then i will decide whether to pull the head, and get a "real" fix, such as a replacement head.

[Mo]

Sounds like you are a go for this season but I'd like to strongly advise you replace the head. MMI sells new and perhaps used as well. If you give Ken a call you could have gaskets and spare head on hand so that if it leaks again you could just change it out.

Keep in mind that on occassion head bolts leak post head removal and people use permatex to ensure it doesn't happen. Stud may or may not cause a problem but I'd be looking at doing it when just before you winterize the boat. That way you won't be in a rush in the spring, have ample time to get it done etc.

Good job and good luck.

[sailingdon]

Mo - i like and will adopt your plan. Thanks for the advice on head bolts and timing of the work.
Sailingdon
Amytar
C&C 27

[Mo]

Mo - i like and will adopt your plan. Thanks for the advice on head bolts and timing of the work.
Sailingdon
Amytar
C&C 27

Keep in mind that once you do the job, if on the hard, you run the engine up to temp for a while. This is to ensure no head gasket leak allowing water into the top end or oil over storage period...just a precaution. Just ensure all is good with it before you put her away for the winter.