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
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
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