Water bubbling out around spark plugs-need help

[BobA]

I'm imbarrassed to even post this, but I'm almost at wit's end. There are a lot of details I can add but I'll try to make it short. (I'm sorry this turned out longer than I would like but I don't know how else to let you know the details.)

Recently I overhauled the carb, replaced the coil and replaced the spark plugs (used conventional never seize, which I now see I should not have) in an attempt to put an end to a stalling problem that occured only alfter an hour of running. I then started the engine and put it under load at the dock. It ran fine. BUT, soon after putting it under load, significant steam and some liquid appeared bubbling up around several spark plugs. I have never seen this before. If this had been occuring before my maintenance I had not noticed it, but I think it had not. I removed the plugs, carefully cleaned the seats and reinstalled the plugs again with their compression gaskets torqued to 30 ft pds. Same result -- steam and water from around the plugs under load.
I next removed the head. A machine shop leveled it (slight warpage), magnafluxed it, and refaced the plug seats. No cracks. I installed it with two new gaskets from MM and also with spray on copper sealant (recommended by a friend who is in the business of overhauling model A ford engines). Torqued it to 35 ft pds. Waited a day and retorqued it. Put in a set of new plugs torqued to 30 ft pds. Started it and put it under load. This time even more water came from around one plug-not just steam, but enough to run down to the next plug. So I concluded I must have a cracked manifold. Removed the manifold, brought it home and tested it with water and thee feet of head using a hose (Don's suggested approach). No leak. One important thing I have not done is test the compression. (No good excuse for that except that the boat is 130 miles from home and I've simply not thought of this when the head was on or when I was at the boat. My better thinking comes on the drive home.)

I've never seen anything like this before. I've had the head off before and never had a problem. I do make mistakes and am very capable of doing dumb things (I'm now 70), but I've worked on cars all my life and am pretty comfortable with what I'm doing and how engines work. I am baffled.

BTW, the engine sounds and runs great even when the water is bubbling around the plugs. 1900 rpm under load -- which is normal. idles great at quite low rpm. No sign of a miss or anything.

1) I can't understand where the water is coming from?? 2) I can't understand how, even if water is getting in the cylinders, how it comes out past the torqued spark plug gasket. And 3) I can't understand how it can be running perfectly with water obviously getting into the cylinder.

I did make a mistake after installing the head. I failed to retorque the head after bringing it up to temperature and putting it under load. Could this be the problem and would it answer my above three questions?

Unless anyone has a better idea, on my next trip to the boat I will run a compression check. Then I plan to remove the head again and give it another look. Has anyone heard of a leak from the head water passages into the plug threads? I also plan to fill the block water jacket with water and see if I see any leak into a cylinder. (the leak btw, fist showed up on three plugs, but only one I think since I put the head back down.)

Any ideas will be very appreciated. Is 35 ft pds still the correct head bolt torque?

I've always winterized with antifreeze, plus I'm not sure it gets cold enough to freeze the engine here in NC, plus I see no evidence of freezing.

I have no leaks in my exhaust system. Cooling water is coming out the exhaust like usual. And after the most recent startup/water problem, I removed the exhaust hose from the water lift muffler. Only about 1 inch of water was in the bottom, which I assume is normal. I believe there is no chance water backed up and over into the exhaust manifold from the muffler.

BTW -- I have subscribed to Don's bulletin's since it was first mentioned in Practical Sailor, and still have them all. What a wonderful service he provides.

Bob

[Dave Neptune]

Plug water

Bob, my guess from the information provided is the you have and had a "small hairline" type crack t one of the spark plug holes. After machining the crack is more exposed however at least you now know where to look.
If your plugs weren't seating before machining a little fuel and condensation from the burning of the fuel will allow a bit to work out the threads.
It sounds as if you should "magnaflux" the head if you can't see a crack with magnification. The water has to come from the head to get to the plug holes, there just aren't many other ways to explain your symtoms.

Dave Neptune

[rigspelt]

Is there any chance the water is dripping from somewhere above the engine, pooling un-noticed around the plugs, and then becoming noticeable when the head heats normally as the engine warms and boils the collected water?

[BobA]

Thanks for both of your comments. I appreciate it.

Rigspelt -- No chance it is dripping. It is definitely coming from the plug holes.

Dave -- What you say is consistent with my thoughts. Your statement that "The water has to come from the head to get to the plug holes, there just aren't many other ways to explain your symtoms." Is really helpful! and, I might add, comforting. If at worst I only have to buy a head, that is great. My thoughts are based on applying logic to the questions I posed, but I haven't had enough experience to know if what I was thinking is possible. Your comments make sense to me. Thank you again. I'll call the machinist tomorrow and ask if he looked at the plug threads. I did ask him to magnaflux the head when he machined it but I don't know if he looked at the threads. In any case, the next step will be to run the compression test. Then I'll take the head off again and look at it carefully -- maybe ask the machinist to look at the threads. And at worst, a MM head. Thanks again for the support.

BTW, I see no indication of water in the oil, although I haven't run it more than maybe 10 minutes since observing the water. At least that is some further support for the idea that the water is coming in around the plug threads.

I can hardly say enough good things about Don for starting this Community Message Board and everything else he does for us. I've long been very happy with my gasoline Atomic 4 (over 30 years now) as there is essentially nothing I can't repair while cruising. But without his support and his parts supply, I'd be thinking diesel, much effort, & $$$ this time.

As a further comment -- my original stalling problem was almost undoubtedly gunk build up in the tank from very old fuel -- I sail much more than I motor. I'm now rather experienced with cleaning a gunked up tank without removal. If anyone is interested in that, let me know and I'll elaborate on an appropriate section of this site.
Bob

[msmith10]

BobA,
I certainly would like to hear your experience with cleaning a tank in place.

[BobA]

Fuel Tank cleaning

Mark,

I'll post a note under "Discussion Topics" "Fuel System"

Bob

[keelcooler]

Bob, No water in oil or combustion chambers. Could be a head crack adjacent or under the lift fitting ring. It also could be coming up one or more loose rusted head studs that thread into the block cooling jacket. Did you pull and reseal the studs when the head was off? Try to trace the source, applying baby powder to the dry head helped another owner trace his leak. Thermostat housing and gasket surface are also suspect. The spark plug holes are the low sumps when a leak occurs on top head surfaces. Good hunting.

[Bob Grenier]

Bob A,
Look very closely at the head bolt closest to the plug. Check out this thread. You may be experiencing the same thing.

http://www.moyermarine.com/forums/showthread.php?t=2789&highlight=Head+crack

Some times this leak looks just like it's coming from the plug because it's the lowest point on the head. And that’s the first thing you see. So look close.

Good luck,
BOB G.

[BobA]

Very helpful comments. It helps a lot to have you all's thinking and hand holding on this. Otherwise it is easy to get mentally down dealing with this sort of problem.
As I said, I did have the head cleaned and magnafluxed before it was machined. This particular machinist owns the shop, but he personally specializes in heads. He is very experienced!! I've got a call in to him to ask again about the possibility of a crack into the plug threads. Also I'll ask about the possiblity of a crack along the alternatory mount. However, it is unlikely he would have missed that, and I believe the water is originating around the plug seat.
I did not change the studs. I simply got cheap and ignored the advice to do so. A dumb decision in retrospect. However, I did look carefully at them and there was no sign of hour glassing. Also, the nuts all came off -- I'm sure none of the studs turned. I checked the torgue on several nuts before removing them and they were at 35 ft pds. I did not check them all but don't recall any nuts coming off more easily than others. But I agree, the studs are something good to look at and probably the alternator mounting studs in particular.
Most helpful to me is that the corrosion around the plugs in the photo appears to be exactly what I would expect to result from my problem. From that and your comments, it sure appears that I need to focus on the head and studs. I'll keep at it and report back. This may take a while as the boat is 2 hours away and I can only get down there about one day each week. Good that sailing season is about over. I envy those who live near their boats.

Bob (1975 Pearson 35)

[Mighty Pearson Owner]

Water on head

One place my head "rotted" out was the recessed area my spark plugs set in..it was not readily apparent and when the engine ran, the water would ever so slightly collect..

I fixed it by getting a "new" atomic 4 from a guy who had a "good" friend that told him his block was cracked when he had a lot of water running out of it..and donated the engine to me and put in a diesel..I changed the water jacket side plate out with a new one..and it is going in the new owners boat this weekend..grin

yah, the Mighty Pearson Owner now owns a Beneteau

Thanks for all the memories!

[BobA]

I talked to the machinist. He said he did magnaflux the entire head. He said no cracks showed up. He said it is possible that a crack can open when the head heats. (The water/steam around the plug, btw, only shows up when the engine is up to temperature, so some chance this could be it.) He said the next step is to bring the head in and he will pressure test it in water. I'm not sure how he does that. I'll report the results in a week or so. Seems to me, from my observation and from you all's comments that the problem has to be with the head. I'm to the point where regardless of the results of the pressure test, I'm about ready for an after market head. This is not fun anymore.

Bob (1975 Pearson 35)

[High Hopes]

Hello BobA,

I haven't read the entire thread here, but I had the exact symptoms as you described. My problem turned out to be a crack near the lifting eye. I would forget about reseating the plugs. I found this by looking for a water stain trail - I use raw water to cool the engine and raw water shows up pretty quickly. When it boils, it doesn't smell very good either.

You might make dams with plumber's putty to divert water flows along the top of the head to isolate the source. Maybe build them between the spark plugs or around a suspicious stud. See the pic below of the crack in my head.... I mean the engine head. This crack was only visible when I polished the area and smeared some sludge across it. It was also hiding under the lifting bracket. A small trickle of water would flow towards the rear of the engine and pool around the last plug. The head wasn't hot enough in other areas along the way to boil the water. Hope this helps.

Steve

[67c&ccorv]

Curious to discover whether the crack was caused by using the lifing eye for its' intended purpose - lifting the engine in and out of the vessal.

Any thoughts?

[sastanley]

Steve - welcome back!

[High Hopes]

Curious to discover whether the crack was caused by using the lifting eye for its' intended purpose - lifting the engine in and out of the vessel.

The crack was found after the engine was installed. It would have been better if it cracked on the way out of the boat.

Somewhere on this forum I posted vector drawing showing that the lifting bracket pushes down on the head with 1100 lb. of force. The problem is that the bracket eye is offset from the lifting bracket studs. This creates a huge moment about the studs. The lifting eye needs to be between two studs, not off to the side.

Steve