Volvo 2010B - Draining fresh water coolant.

[Miker]

I am in the process of winterising the boat which is out of the water, and need to replace the antifreeze in the fresh water coolant. Can I drain the engine while it is cold and then replace the coolant, or should I run the engine and then drain it while it is hot? If the latter, how long should the engine be run to open the thermostat?

 

[Daydream believer]

I change mine cold & just take the thermostat cap off

 

[Miker]

"Thermostat cap". Do you mean filler cap? If so, I did that in the past but wondered whether that was correct.

 

[VicS]

I am in the process of winterising the boat which is out of the water, and need to replace the antifreeze in the fresh water coolant. Can I drain the engine while it is cold and then replace the coolant, or should I run the engine and then drain it while it is hot? If the latter, how long should the engine be run to open the thermostat?

With a cold engine see the section on the "Cooling system" in the owners manual and follow the procedures described for draining, flushing, and refilling,

You take the cap off to allow air to enter quickly ...... just like you do when changing your car coolant!

Take note of the warning not to remove the filler cap while the engine is hot

Follow the procedures described in the manual for the seawater system too


If you have mislaid your manual down load a copy from http://www.volvopenta.com/volvopent...lication_search/pages/publication_search.aspx

 

[Daydream believer]

"Thermostat cap". Do you mean filler cap? If so, I did that in the past but wondered whether that was correct.

I used that term as my one has 2 caps. One for the reservoir & one on the engine

 

[cmedsailor]

I am in the process of winterising the boat which is out of the water, and need to replace the antifreeze in the fresh water coolant. Can I drain the engine while it is cold and then replace the coolant, or should I run the engine and then drain it while it is hot? If the latter, how long should the engine be run to open the thermostat?

There's no need to be hot. The coolant is so "thin" (not like oil) so it drains very easily even when cold.

 

[nigelmercier]

... follow the procedures described for draining, flushing, and refilling ...

I'm going to be doing this for the first time in 13 years on an MD22. Should I do an acid flush?

 

[Miker]

Thanks again. I shall replace the coolant first then run the engine a bit to get some water/antifreeze mix through the raw water side.

 

[VicS]

I'm going to be doing this for the first time in 13 years on an MD22. Should I do an acid flush?

If this is the first time the coolant has been changed in 13 years a good flush out with a car type cooling system cleaner would be a very good idea.
With only one charge of water in all that time the system is not likely to be heavily scaled so an acid clean may not be necessary.

Something like Holts Speedflush or if the system is scaled Holts 2 part Radflush

 

[nigelmercier]

With only one charge of water in all that time the system is not likely to be heavily scaled so an acid clean may not be necessary.
Something like Holts Speedflush ...

It's been topped up though, possibly with tap water, and I've got acid

Speedflush is Sodium Silicate, what does that do then?