freeze plug woes

[Nate]

Well, what have I gotten myself into...? briefly - I have a '78 Pearson 10M with a very nice A4 that has run well and reliably for the past year (the first year of my ownership). This past weekend I cranked (and cranked and cranked) and got the engine started for the first time this spring. After 30-60 seconds, I backed off on the choke, applied throttle, and flooded the engine. After cranking a few more times, I gave it a rest. Later (20 min.) I took a look below, and noticed water 'splash' all around the exhaust side, and saw that one of the freeze plugs in the manifold was missing. The missing plug is at the flywheel end, which is also the top-most point due to installation angle. I have searched and cannot find the missing plug. After some brief reading on this forum, I am wondering if this plug was forced out due to freezing, or perhaps due to my continuous cranking with the water intake valve open (or any other reason). Also, how many plugs are on this engine, and where is each located? I want to do a thorough inspection to be certain that no other plugs are missing.

Thanks! (and sorry for the long-winded opening...)

PS: The boat is in freshwater year-round in NC. My over-winter procedures were admittedly limited, consisting primarily of good reliable electric heat on-board during cold snaps, with occasional brief engine runs at the dock.

[David Masury]

You can get freeze plugs at any good automotive store and they are not difficult to put in. It is quite possible that during a cold snap and without antifreeze in the block the ice pushed out the one you had.

I would suggest that once you installnew freeze plugs and you get the eingine going again, that you do a flush and perhap consider installing a fresh water system. The fresh water system will allow you to have antifreeze in the block year round, thus eliminating and further chance of this happening again.

David

[High Hopes]

There are rubber ones that you can install with a wrench. The plug squeezes out and makes a tight fit. I used two of these on the exhaust manifold and they worked well.

[CalebD]

Since it sounds as though you have a raw water cooled engine set up it may be advisable to keep the raw water intake valve closed when you can expect long cranking times (eg., first start after long time idle). Cranking the engine too long with the engine not starting up will cause a lot of water to enter the exhaust system which can back flow into the engine and cylinders. In your case, some of that water exited via the freeze plug hole.