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Well it appears I have either gotten carried away or am doing due diligence. Either way I have a lot of work to do and would be very grateful for any input from fellow A4ourians.
After an overheating episode that seemed to result from some restrictions from the exhaust and doing a vinegar soak/flush I thought I had things going well again as temp improved and motor ran well for a 40 min. test run. After a couple sails where I run motor about 30min off mooring and 30min. back she began to run on only 3 cylinders and possibly just 2 as cylinder 4 was not firing at all and 3 was intermittently not firing. Compression test showed 0 on 4 and about 90 on the other 3 cylinders.
After removing valve plate it was clearly stuck exhaust valve on 4 and intermittently sticking valve on 3. Unable to free valves I removed head and was able to free the valves and got to looking at exhaust manifold and piping and, well long story short I took the whole thing apart. My thinking, and after talking with Ken about it while ordering new head, valve and exhaust gaskets, is that to take her apart this far and not to do a proper valve job would risk a recurrence and that being the case I also took off the water jacket plate and will be cleaning that all up as well cuz it seems that the clogging likely came from that area. Also while cleaning water passages from block deck above it surely needed some cleaning.
I am attaching a couple pictures of the exhaust for some input as to whether the design is problematic because the water input coming in at the top as it does and not further down toward the water lift muffler also the pipe where the hose comes in seems to reduce and ght that not create pressure or some other trouble? Also could running on three cylinders cause a lack of exhaust pressure sufficient to expel water and eventually allow it to ba c k up into cylinders as it clearly has? Manifold had water in it in the area highlighted in the recent newsletter about "exhaust reflux". . Also as I now have the manifold off and it looks pretty gross what is the best way to clean it up and get it ready for re-installation? Any way sorry to be so long and thanks for any thoughts.
After an overheating episode that seemed to result from some restrictions from the exhaust and doing a vinegar soak/flush I thought I had things going well again as temp improved and motor ran well for a 40 min. test run. After a couple sails where I run motor about 30min off mooring and 30min. back she began to run on only 3 cylinders and possibly just 2 as cylinder 4 was not firing at all and 3 was intermittently not firing. Compression test showed 0 on 4 and about 90 on the other 3 cylinders.
After removing valve plate it was clearly stuck exhaust valve on 4 and intermittently sticking valve on 3. Unable to free valves I removed head and was able to free the valves and got to looking at exhaust manifold and piping and, well long story short I took the whole thing apart. My thinking, and after talking with Ken about it while ordering new head, valve and exhaust gaskets, is that to take her apart this far and not to do a proper valve job would risk a recurrence and that being the case I also took off the water jacket plate and will be cleaning that all up as well cuz it seems that the clogging likely came from that area. Also while cleaning water passages from block deck above it surely needed some cleaning.
I am attaching a couple pictures of the exhaust for some input as to whether the design is problematic because the water input coming in at the top as it does and not further down toward the water lift muffler also the pipe where the hose comes in seems to reduce and ght that not create pressure or some other trouble? Also could running on three cylinders cause a lack of exhaust pressure sufficient to expel water and eventually allow it to ba c k up into cylinders as it clearly has? Manifold had water in it in the area highlighted in the recent newsletter about "exhaust reflux". . Also as I now have the manifold off and it looks pretty gross what is the best way to clean it up and get it ready for re-installation? Any way sorry to be so long and thanks for any thoughts.
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