Water circulation

R

roemere

New Member
Apr 13, 2013
50
IL
Boat Info
1977 SRV220 Cuddy
Engines
Mercruiser 888 (302)
Put on the muffs and fired up the boat for the first time this season but something does not look right--the boat was definitely taking water in thru the muffs, but water was coming out the drain (plug was out) and also being pumped out by the bilge pump. There was no water in the bilge before we hooked up the muffs. Is water taken in thru the muffs supposed to end up in the bilge? Ran the engine for a good half hour and it never got hot. Where is the water supposed to go as it circulates thru the engine cooling system? Where is it discharged? I thought it was supposed to be discharged thru the prop...if so, what am I looking at for a problem?
 
How was the boat winterized? You are correct that the water should NOT be ending up in the bilge. Take a look at the engine while it's running and see where the water is escaping. Hopefully, it's just a missing drain/petcock/loose hose and not a cracked block.
 
Boat was drained and antifreeze run in to replace water. I just talked to the guy who winterized it for me and he said when he ran it during winterization it did the same thing---water/antifreeze went in thru the muffs and came out the drain. So it was doing this even before it was winterized.
 
Upon inspection water is coming out of two 1.5" diameter holes on both sides engine and we found two metal (brass?) "caps" or "discs" in the bilge. Markings on the discs are "1 1/2 1510SC".....I am guessing these are "freeze plugs" or "core plugs". Looks like the winterization was not adequate for the extra-cold winter....my oil looks good (not gray or milky) what are odds I dodged a big bullet and block/head survived?
 
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Something does not add up yet. What time of year was the boat winterized? Did you have freezing weather before this was done? Those plugs are designed to pop, from expanding ice. The purpose is a last ditch effort to protect the block from cracking.
 
Yes, they are technically "casting plugs", but they also tend to serve as freeze plugs. However, MOST of the time, they do not pop out to save the block. They also don't make a habit of popping out by themselves. It certainly sounds like the engine wasn't winterized early enough. Maybe... MAYBE you got lucky and they popped out before any damage was done. Put new ones in and see what happens. There's no way for us to tell you if there's any cracks - you can take a look, but you may not notice anything until you run it again.
 
I am pretty sure it was winterized before freeze, but apparently not thoroughly or to a low enough temp....local parts store has rubber expanding plugs, are these adequate? Or do I need to replace with the metal ones? The rubber ones would go in easily, as motor mount is obstructing. May need to pull motor to drive in a metal plug....
 
Once plugs are replaced, what should I look for? I have heard gray/milky oil....anything else that would indicate (or better yet rule out) a crack?
 
Grey, milky oil is bad, also very bad is oil in the bilge, and keep an close eye on temp. You said you ran it for 1/2 hour and still had oily oil, that is a very good sign that you should get a lottery ticket. Also keep checking for water leaks, or any leaks for that matter.
Ive seen frost plugs fall out of a truck engine, 350,
 
My wife tells me it was later than usual when we had the boat winterized, and she thinks there had been a freeze, but not a "hard freeze" (??)...[edit: I guess a "hard freeze" is when it is cold enough for a long enough time to damage/kill plants/flowers]

I bought some of the expandable rubber engine plugs to get the cores plugged so I can run it and check for leaks, water in oil, oil in bilge, etc. If all looks good, then I will replace with metal plugs...
 
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Who winterized the boat for you? Was it a mechanic, or just "a guy"? I would have serious concerns about anyone who sees cooling water dump into the bilge without raising an immediate red flag with the owner. The fact that he didn't tell you at the time means that either he's incompetent (never let him touch your boat again), or saying "Yeah, I saw the same thing" to cover his butt, because he didn't actually winterize your boat properly and is now trying to say it was already damaged before he got to it.
 
" I just talked to the guy who winterized it for me and he said when he ran it during winterization it did the same thing---water/antifreeze went in thru the muffs and came out the drain. So it was doing this even before it was winterized. "

Either he`s wrong or you never used the boat last year.. To say you winterized a boat and saw the AF draining out the drain hole says the plugs were already out from freezing.
 
We used the boat, so if AF was coming out the drain during winterization it had to have been done too late and had already frozen (unless there is another way for those plugs to come out). It was not a mechanic, just a guy doing it for us.
 
Plugged the cores, started the boat and found a crack. The port exhaust manifold end cap (where fuel filter bracket is mounted) has a big crack just below the water inlet. Going to try to weld it enough to stop the leak so we can run it for further tests. Also looks like some type of "coil" or "tube" inside the exaust manifold might also be cracked...what are ramifications of this?

Where can I find part number to order a replacement end cap? Or replacement exhaust manifold assembly?

1977 Mercruiser 188/888 (302)
 
Welded the end cap to plug the leak (temporary fix) so we could run the boat to check for more leaks. while boat was running we did not see anymore leaks, but the engine died and now it is hard to turn over, and have not yet managed to get it started again...

Prognosis?
 
roemere said:
Welded the end cap to plug the leak (temporary fix) so we could run the boat to check for more leaks. while boat was running we did not see anymore leaks, but the engine died and now it is hard to turn over, and have not yet managed to get it started again...

Prognosis?
Click to expand...
Time to check for water in the cylinders.
Water doesn't compress. Repeated attempts to start the motor will result in damage to it if there is water in a cylinder.
Pull the plugs, and try to turn it by hand. If water comes out of a cylinder, then you've found your problem.
 
You should pull the spark plugs and get the water out sounds like there is water in the top of the motor from the crack in the exaust manifold And pull them out soon before the motor seizes up
 
If the antifreeze was coming out the block and obviously not getting to the exhaust manifolds, it probably was not getting to the cylider heads, now with what appears to be hydro lock I would expect a cracked head or two.
Im sorry to hear that.
 
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