Missing drain plug....Will I have to replace engine?

[Crown416]

I'm new to the forum but not new to boats themselves. This is my first I/O. It is a 2000 Crownline 225 with a Mercruiser 5.0 EFI. I just winterized(pulled the plugs) the boat a couple nights ago. I called Mercruiser to make sure I pulled out ALL the plugs but they told me that there are 6. I only found 5. It got down to 32* last night for about 6 hrs. Am I going to be in trouble?

It seems as though I pulled two off the manifold drains, one off the port side block, one wayyy down on the bottom side of a port side copper pipe that was connected to a rubber hose, and one off the starboard side in the front of the engine just under the belts and alternator. It seems like I must have overlooked the drain on the starboard side block. Would leaving that one in there have cracked the block?

How much would it cost to have the engine replaced as cheaply as possible?

Any and all help/peace of mind is greatly appreciated. Thanks!

 

[Rick Stephens]

6 hours at 32 probably didn't freeze anything inside your block. It is contained and under cover, tends to take colder than that to freeze up. You're right to figure it out now and get it fixed.

That said, both sides of the block have a drain at the same location.

RIck

 

[alldodge]

Agree, look on the starboard side. If we knew what engine you had including the year this could help

 

[Bondo]

Ayuh,.... Welcome Aboard,.... I agree with Rick, last night probably didn't do any damage,.... But,....

Today, as soon as possible, pull the block drain on the starboard side, it's down low just forward of the starter,....

Did ya get a good flow of water outa the drain holes after ya pulled the plugs,..??
I always poke, 'n prod 'em with a nail or deck screw, to knock the dirt, 'n debris outa there so All the water can drain,...

 

[fhhuber]

Not likely for the engine to retain sufficient water to damage it with just one of the drain plugs left in even if it does freeze... There's going to be room for the water to expand.

Its still better to find that last plug and get it out, but you'd have to have a few worst case conditions all at once for it to crack the block.

 

[H20Rat]

If it was only at 32, there is absolutely no way it would have froze the block, even full of water. It takes mid to low 20's for at least a couple hours before you really need to worry about it. Lots of insulation around it, assuming the boat is under a cover, and the engine is in a standard compartment surrounded by fiberglass, wood, and cushions. (all great insulators) Engine compartments, by default, are designed to have great insulation.

 

[Bondo]

Not likely for the engine to retain sufficient water to damage it with just one of the drain plugs left in even if it does freeze... There's going to be room for the water to expand.

Ayuh,.... I gotta take exception to that,.... The pressure will be outward, not back up through passages,....

That cavity is more captive than open, it ain't like a 1/2 full glass of water, more like a very full glass soda bottle,...

Many years ago, a mentor of mine said it takes 6 hrs at 26? to crack a block,....

I ain't tried to prove 'im right or wrong, but it appears to be quite True, in my experiences,.....

 

[superbenk]

Totally agree with Bondo about poking & proding in the drains. I've freed a lot of water that way that would otherwise have been stuck n there to freeze.

Also, it's good practice to disconnect & make sure the power steering cooler is drained too. Located in the back of the engine just over the flywheel bell housing. Mine is usually dry but it never hurts to pull the hoses & make sure.

 

[crazy charlie]

If you are not certain about getting water out then put some antifreeze in .Can make the difference of freezing or not freezing and i prefer not freezing.I know i am in the minority as my old friend Bondo will confirm but I am 100% in favor of winterizing with antifreeze rather than dry.Charlie

 

[Crown416]

Thank y'all for the peace of mind! I certainly appreciate it. By the way, the serial number to the engine is 0L683702 if that helps any.

Just for kicks, how much would it cost to have the engine replaced if there were to be a crack in the block?

 

[Crown416]

Where would I be able to put antifreeze in it? I've seen videos of people sucking it in thru the drive but heard bad things about that. Also I've heard of people pouring it into the thermostat housing. Is that where I should pour it?

 

[crazy charlie]

pull all hoses off 1 at a time and pour some antifreeze in each hose AND where the hose was attached, as well as in the tstat housing pulling the tstat of course.Charles

 

[NHGuy]

That port side drain is a bear to reach. It's low and behind the incoming water lines, but it IS there. If you have an old coat hanger laying around that's another good prod to break the rust skim inside the water jacket. Do the poke and prod to both sides. Do it today and you will feel better.
Engines cost a lot, they vary in price whether you change it yourself or pay someone. It's thousands, so just get a little uncomfortable to reach that plug and keep the money for yourself.

 

[alldodge]

Thank y'all for the peace of mind! I certainly appreciate it. By the way, the serial number to the engine is 0L683702 if that helps any.

Just for kicks, how much would it cost to have the engine replaced if there were to be a crack in the block?

Air doesn't freeze, but once you get all the water out, knock your self out if that's what you want to do

Your drain on the starboard side should be located with the knock sensor

 

[thumpar]

I was going to say the starboard side is in the knock sensor. It makes it much easier to get to than the port side drain.

 

[keith2k455]

The plug you missed is the hardest to reach, but it is there. Just reach under and find it. On mine that is the one I get the most scratched up pulling.

 

[Lou C]

If you haven't already done this:
The big hose that goes from the thermostat housing to the front circulating pump also holds a lot of water. Disconnect it at the lower end and let it drain; this drains the water pump which will not drain fully from the block drains. That and make sure you poke all the drains to ensure they drained.
I agree at 32* for that amount of time would not freeze the block but you got lucky.
And like Charlie I do add antifreeze and feel that it prolongs engine life in salt water.
I use the -100 stuff with corrosion inhibitors.

 

[StarTed]

During my younger days I had a '39 Chev that I forgot to drain in temps 28 or slightly less for at least 8 hours. The next day I started it up and it soon overheated so I shut it down then remembered that it had straight water in it. The fan may have cooled the radiator more and it froze shut preventing any cooling for the engine. I let it soak for a couple of hours and expected the worse. All was well but that didn't cure the oil burning which was about 3 quarts per tank of gas. Those were the days'

So I feel safe saying that you have no problem at 32 but make sure that it drains completely. Probe the holes again after it seems to be all the way drained. I've seen them close up again from rust, crud and casting sand.