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Mercruiser 4.2 overheat damage?

whiteside said:
Not too bright are ya? There's still thousands of them on the water. Including mine, an 87 with original gearset. Don't need you or other guys who are scared of those big bad Cobras, like Einstein of this board.
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Listen up Shade Tree, If you are busy working on old obsolete crap, more power to you. Cobra drives around us are collectively just worn out.

Most free boats have an OMC drive attached to them. OMC outboards are going in the same direction.
 
o2batsea said:
So, OP, was it just the blue drain plug was out or was there more to this?
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Good question, I felt his explanation was one was out on one side and that was the cause of the "over heat". So only one side of the system was affected.
Like I said, if so then only a few issues may have resulted but no damage to the engine as there was water circulating just not thru the one exhaust.
 
From what I’ve been told it was a drain plug. The seller said he verified this after we got off the lake. This seemed consistent with what I saw on the lake. We ran it for a few seconds while still on the lake after things cooled down. I saw a steady stream of water shooting out perpendicular to the engine block but the source was hidden by the right front engine mount. I tried to get my head low enough to see where it was exiting but was unable to. The eater certainly looked like it was co I got out a hole vs. a crack.

Hoping to get get a full report from his shop...time will tell.

Bruce
 
Fourshipp said:
From what I’ve been told it was a drain plug. The seller said he verified this after we got off the lake. This seemed consistent with what I saw on the lake. We ran it for a few seconds while still on the lake after things cooled down. I saw a steady stream of water shooting out perpendicular to the engine block but the source was hidden by the right front engine mount. I tried to get my head low enough to see where it was exiting but was unable to. The eater certainly looked like it was co I got out a hole vs. a crack.

Hoping to get get a full report from his shop...time will tell.

Bruce
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Chances are there was no damage caused by the missing plug.
 
Correction: I double checked with the seller about which plug was missing. He described it as the aluminum block core plug behind the right forward engine mount.

Bruce
 
Oh, Not good!!

That typically means boat was NOT winterized properly.


I would suggest walking away unless you want to hear what the marina found............

Core plugs are typically brass in marine engines. Auto are steel.

Aluminum and steel will corrode in a marine environment, but he may have been mistaken and simply called it aluminum
 
Khos, today '09 regal with 3.0 Volvo-Penta, freeze plug in bottom of exhaust manifold was laying in bilge took Tele- magnet and picked it rite up. Original plug still had black paint..
 
Mikey N.C. said:
Khos, today '09 regal with 3.0 Volvo-Penta, freeze plug in bottom of exhaust manifold was laying in bilge took Tele- magnet and picked it rite up. Original plug still had black paint..
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WOW good job Mikey....... I am sure you are one proud (?).......Are you sure it was black paint and not somten else? A Tele- magnet........is that like a Tele-phony?

Hey Mikey Your so fine hey Mikey!
 
kghost said:
I would think its what you stuff up your A$$ at night before going beddy by....

Or maybe you suck on one when your thumb looses its turd taste...

Maybe you can solve the mystory for us all?
What is a freeze plug.....is it anything like a freeze pop? I like grape flavor.
I bet you like the big smelly brown ones!
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Genius, on an OMC Cobra what is the purpose of the exhaust bellows having slits on the bottom of it, Ace?
 
whiteside said:
Awwwwww! Afraid of those big bad Cobras biting you in the a$$? BAHAHAHAHA
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You talk of all these cobra repairs you know how to do, you know you're right I'd don't know how to do them.... because in 25 years of running alphas I have had to do so much less maintenance

do everyone here a favor and shut up
 
@Fourshipp, this is not a sign of a healthy engine. Sure, one could definitely replace the plug but it is a signal that something bad happened. These things don't just fall out without some significant force (like freezing water), or due to the (machined) hole they are plugging becoming larger and allowing it to fall out (usually from a crack in the side of the engine caused by expanding water when it freezes).
Poor winterizing is one of the major causes of premature death in marine engines. IDK if you are in an area that gets cold in the winter, but if so, this is always the first thing one checks on at springtime recommissioning.
Keep looking. Your ship will come in!
 
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Thanks for the insight. We will wait for the shops report and see what the damage and repair are. Who knows? If they put a new engine in then it may be a good deal. Then again, they may sell it as is and be done with it. There are several nice boats that have come in the market since this all started. Back to the search.

thanks for helping a newbie out.

Bruce
 
I have seen many which a freeze plug/core plug popped out due to poor winterizing, not, not winterizing and the plug was replaced and all was fine.
so there is hope.
 
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