Drain block in CA?

[larry1167]

I live in CA and keep my boat in my insulated garage. It never gets below 45 degrees in the garage. I am going to fog and change the oil today. I don't have to worry about the block freezing. What are the pros/cons of leaving the water in the block for a few months? The only thing I can think of is rust. Will more rust develop if the block is full or dry? What are some other considerations? I have Chevy 350. Thanks.

 

[zbnutcase]

Re: Drain block in CA?

It will rust faster if drained.

 

[larry1167]

Re: Drain block in CA?

It will rust faster if drained.

That's what I was thinking. Thanks Zbnutcase.

 

[bruceb58]

Re: Drain block in CA?

If the boat is in El Dorado Hills I would drain it. Doesn't it occasionally drop into the 20s there or is the garage keeping it warmer?

 

[larry1167]

Re: Drain block in CA?

Garage is keeping it warmer. It's insulated and has drywall. Sometimes it drops into the 20's at night, but the thermometer in my garage never gets below 50ish. Daytime temp average is 50+ in the dead of winter.

This is the first year I haven't drained the block. I was a bit concerned until I started monitoring the temp in the garage. Now I am not concerned. I even bought a reptile warming rock and put it in the bilge. Using this kept the temp at 60. For pease of mind, I turn it on when the temp dips below 30 for the night. Probably not needed but it was my security when I didn't know how cold it would get in the garage.

 

[larry1167]

Re: Drain block in CA?

I should clarify... using the warming rock kept the temp at 60 in the engine compartment.

 

[HT32BSX115]

Re: Drain block in CA?

I should clarify... using the warming rock kept the temp at 60 in the engine compartment.

Um, "Warming Rock"?




If you think you "need" a "warming rock", then you should drain it.

My current boat belonged to by brother back in the 90's. He lives in Novato, Ca, (Between San Rafael and Santa Rosa) and was there when they had overnight temps in the TEENS and daytime temps below 25 for about a WEEK!!

Somehow he got the insurance company to replace the engine (a wunnerful OMC King Kobra 460!!) but only because they couldn't PROVE that they sent him a freeze damage "disclaimer"!!! (his was outside though)



If you're satisfied that it doesn't get below freezing in the garage, then don't worry about it! If you're not sure, and you're using the "warming-rock" to have "peace-of-mind", then drain it........

"Murphy" usually takes care of the electricity for you at the most IN-opportune time!!!

 

[larry1167]

Re: Drain block in CA?

Um, "Warming Rock"?




If you think you "need" a "warming rock", then you should drain it.

My current boat belonged to by brother back in the 90's. He lives in Novato, Ca, (Between San Rafael and Santa Rosa) and was there when they had overnight temps in the TEENS and daytime temps below 25 for about a WEEK!!

Somehow he got the insurance company to replace the engine (a wunnerful OMC King Kobra 460!!) but only because they couldn't PROVE that they sent him a freeze damage "disclaimer"!!! (his was outside though)



If you're satisfied that it doesn't get below freezing in the garage, then don't worry about it! If you're not sure, and you're using the "warming-rock" to have "peace-of-mind", then drain it........

"Murphy" usually takes care of the electricity for you at the most IN-opportune time!!!

It doesn't freeze in my garage. Lowest temp I have seen so far is 50. That's when outside temp was mid 20's all night long. Got warming rock before winter when I didn't know how warm my garage would stay. I was pleasantly surprised by how warm it stayed. Now I don't have to drain my block every time I use my boat during the winter. I fogged it just in case I don't go for a few months.

 

[stonyloam]

Re: Drain block in CA?

Will more rust develop if the block is full or dry?

I will have to respectfully disagree with zb. In order to form rust (Fe2O3) you need oxygen (O2). If you put the plugs back in after draining the fresh supply of oxygen will be cut off. Either filled with water or air rusting will continue until the oxygen is consumed and then will stop. The difference between leaving it full of air or full of water is insignificant. IMHO

 

[HT32BSX115]

Re: Drain block in CA?

My previous engine (a 1966 Mercruiser inline 6) went 39 years and was probably going to completely wear out before rusting out in fresh water!

It was garage kept and NEVER was fogged.

If you're satisfied that your garage temps will never go below freezing, don't worry about it!

 

[cr2k]

Re: Drain block in CA?

Oh good lets start a thread on the properties of rust!

How about this, if its drained there is more surface to rust.

or

If its drained there will be less moisture to cause rust.


Pick one.

 

[jerryjerry05]

Re: Drain block in CA?

Air causes it to rust faster.Once it starts to rust any air will help it along.Fresh water ain't as bad as salt.Salt water and heat from the exhaust will make it rust faster so flush with fresh and leave it.
If you really want to do something.Drain it,then get some of the red motorhome antifreeze.It's cheap and can be ran right into the water without polluting like regular antifreeze.J

 

[stonyloam]

Re: Drain block in CA?

Air causes it to rust faster.

A fire needs fuel and oxygen. If you have a fire in a airtight room and close the door the fire will consume the oxygen and go out.

Rust needs iron (fuel) and oxygen. If you put the plugs back in the airtight block (close the door) the rusting (fire) will consume the oxygen and stop (go out). Without a fresh supply of oxygen, no more rusting.

My chemistry is a little rusty, but here goes. There is about 0.25 grams of O2 in a gallon of air (air is about 20% oxygen). If all of the O2 was able to penetrate the rust layer already in there and react with fresh iron (not likely) you would make about 3 grams of rust, in a 90,000 gram (200# engine). If filled with seawater under the same conditions @ 5 parts per million dissolved O2 you would make about, guess what? 3 grams of rust. The original point I was trying to make is, if you put the plugs back in there is essentially no difference in rust formation if you store it full or empty. Now...... you could fill it with oil, straight 30 wt or 10W-40 hmmmmm?