How much water left in engine block - winter?

[Robert Wilson]

I need to replace the cooling system hoses. If I disconnect them water will drain from the header and hoses (obviously ) but would the water remaining in the engine block itself need to be drained to prevent frost damage.?

I can't see if there is a drain tap anywhere, so I assume the lowest hose connection will drain most of the water from the galleries etc.

I don't want to leave a heater in the boat for months if there is no need or benefit to the engine; and I can start afresh next season with a good flush-out and renewed coolant/antifreeze.

What does the team think?

Edit: Just a thought. Would the Exposed surfaces in the gallery then be liable to corrosion?

 

[[70521]]

Do you have access to compressed air?

 

[Robert Wilson]

Sadly no.

And that sounds awful messy!!

 

[Spirit (of Glenans)]

Sadly no.

And that sounds awful messy!!

Some engines, such as the Volvo D1-series have a drain spigot low down on the block.
Have you checked your manual.
Info re make and model would help with replies.

 

[Robert Wilson]

Some engines, such as the Volvo D1-series have a drain spigot low down on the block.
Have you checked your manual.
Info re make and model would help with replies.

Of course. Remiss of me to omit it.
It's a Kubota 2 cylinder 13.5HP

I've looked for a drain tap or whatever, but access is not easy (understatement!!).
I have the manual but it's not helpful in this respect.

I suppose what I wish to know is a general question about "water, if any, being left inside a block for perhaps five months over this winter".

I could of course renew the pipes and re-fill straight away, but there are other tasks to undertake which would delay re-filling.

 

[Pye_End]

Drain on the Beta is next to the forward std. engine mount, and is a 90 degree fitting with a plug in it.

Presumably any water in it will be an antifreeze mix??

 

[VicS]

Of course. Remiss of me to omit it.
It's a Kubota 2 cylinder 13.5HP

I've looked for a drain tap or whatever, but access is not easy (understatement!!).
I have the manual but it's not helpful in this respect.

I suppose what I wish to know is a general question about "water, if any, being left inside a block for perhaps five months over this winter".

I could of course renew the pipes and re-fill straight away, but there are other tasks to undertake which would delay re-filling.

It would be preferable to refill with the correct antifreeze mixture. but you need to locate the drain anyway for the routine, 2 yearly ??, antifreeze replacement.

Assuming this is the engine from which the Beta 14 is derived then the attached picture may help you locate a drain plug.

 

[Robert Wilson]

In between the next set of squalls I'll climb aboard and search as suggested.
I'm not sure if my Kubota is in fact the same as the Beta.

Fingers crossed.

Thanks to you each.

R

 

[Hadenough]

Have you got access to a wet vac?

 

[A1Sailor]

It would be preferable to refill with the correct antifreeze mixture. but you need to locate the drain anyway for the routine, 2 yearly ??, antifreeze replacement.

+1.
Anti-freeze has corrosion inhibitor in it - if you drain it, the engine will rust.
I think...

 

[Robert Wilson]

Have you got access to a wet vac?

Yes, but how would that help?

+1.
Anti-freeze has corrosion inhibitor in it - if you drain it, the engine will rust.
I think...

I think you have answered my question, almost....
If I can't get all the water out of the block then some of the old antifreeze mixture will be left and might (?) degrade the new stuff??

 

[jim.howes]

Hi, you should be safe from any frost damage because 1/ what is left in the system should still be an antifreeze mix and 2/ not wanting to appear rude but when water freezes it expands and when it expands and has nowhere to go in the engine block If you are lucky it pushes out the core plugs and if you are unlucky like me it cracks the block (ouch). I myself would change the hoses now and top up with a fresh antifreeze mix as the inhibitors in antifreeze are beneficial.

 

[Robert Wilson]

Hi, you should be safe from any frost damage because 1/ what is left in the system should still be an antifreeze mix and 2/ not wanting to appear rude but when water freezes it expands and when it expands and has nowhere to go in the engine block If you are lucky it pushes out the core plugs and if you are unlucky like me it cracks the block (ouch). I myself would change the hoses now and top up with a fresh antifreeze mix as the inhibitors in antifreeze are beneficial.

Yes, that's true; but if the block is only partially/a little full then there is expansion space ?
Unless....
there are chambers within the block where the water can't expand.
I have now idea about the inside of a block and the coolant galleries.

 

[VicS]

+1.
Anti-freeze has corrosion inhibitor in it - if you drain it, the engine will rust.
I think...

I don't know .... but perhaps I'll try a little schoolboy style chemistry experiment over the next few months.

Yes, that's true; but if the block is only partially/a little full then there is expansion space ?
Unless....
there are chambers within the block where the water can't expand.
I have now idea about the inside of a block and the coolant galleries.

There very probably will be. Therefore if the cooling system does not contain antifreeze drain it completely.

 

[PaulRainbow]

I need to replace the cooling system hoses. If I disconnect them water will drain from the header and hoses (obviously ) but would the water remaining in the engine block itself need to be drained to prevent frost damage.?

I can't see if there is a drain tap anywhere, so I assume the lowest hose connection will drain most of the water from the galleries etc.

I don't want to leave a heater in the boat for months if there is no need or benefit to the engine; and I can start afresh next season with a good flush-out and renewed coolant/antifreeze.

What does the team think?

Edit: Just a thought. Would the Exposed surfaces in the gallery then be liable to corrosion?

How can what's left in pockets freeze, it's anti-freeze/water ?

Any exposed surfaces will corrode, at the same rate as any exposed surfaces on the outside of the engine. If you don't re-fill with coolant within about 300 years you may have some minor pitting.

It's best to drain as much as you can, so one normally removes the lowest hose or opens the drain valve (not too many engines have one these days, yours should). But, any small pockets of old coolant can safely be disregarded.

 

[simonfraser]

climb aboard, is she afloat ? in which case its v unlikely to freeze due to the surrounding water.

 

[essexboy]

Surely if you have drained most of it out the remainder will have plenty of room to expand with no ill effect ?
And anyway the chances of it freezing are very slim ( IMHO)

 

[Robert Wilson]

How can what's left in pockets freeze, it's anti-freeze/water ?

Any exposed surfaces will corrode, at the same rate as any exposed surfaces on the outside of the engine. If you don't re-fill with coolant within about 300 years you may have some minor pitting.

It's best to drain as much as you can, so one normally removes the lowest hose or opens the drain valve (not too many engines have one these days, yours should). But, any small pockets of old coolant can safely be disregarded.

Re-assuring, thanks.

climb aboard, is she afloat ? in which case its v unlikely to freeze due to the surrounding water.

Also re-assuring, thanks.

"Climb aboard"?
'cos she's in the driveway and has been for two years!!

We rarely get very hard frosts here, right on the edge with Gulf Stream influence, but we do get strong northerlies (as we have this last few weeks) and if the temp got below minus 4°C then I'd be very worried, Coupled with the fact that I shall be away a lot between now and March. Sod's Law is that it would freeze like stink the night I'm away!!

So, I'll drain by removing lowest hose, measure and buy the correct hoses/elbows then get the whole lot re-assembled and properly re-filled ASAP.

Thanks one and all.

 

[Spirit (of Glenans)]

Assuming your Kubota is the same as the Beta 14, page 11 of the manual has details of the draining procedure. See link : http://www.betamarinenw.com/Engines/Resources/Manual - Beta 10, BZ4#D8E09.pdf
IMHO an engine filled with the correct antifreeze solution should not normally freeze up in any part of the British Isles, particularly if the boat is kept afloat.

 

[A1Sailor]

The engine will have an anode although they aren't usually very big - so maybe it will have had an anode! It will also be attached to the anode on the outside of the hull. I would still keep the engine topped up with fresh water/anti-freeze.