Momac
Well-Known Member
Can or should this be used to flush antifreeze cooling system
Or is it better to flush with water only?
Or is it better to flush with water only?
Flushing coolant system on Volvo Penta kad32 or the like
- Thread starter Momac
- Start date
Boater On Thames
Well-Known Member
My understanding is yes. I used some central heating cleaner bought from the hardware store. I think they are the same thing.
Plum
Well-Known Member
My VP workshop manual (which covers the 32 series) says "The system should be flushed carefully with tap water when changing the coolant. Flush until the water which runs out of the draining holes is clean." It says nothing about using any cleaning agents so I would not use any.
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Bran
Well-Known Member
I asked Holts at what concentration do I use in my Perkins and had a quick reply not recommending using it as they have not tested it on any marine engines! I am probably just going to repeat flush with water.
Momac
Well-Known Member
I also just used water but really I would not have thought a marine engine any different to a vehicle engine in principle.
Bran
Well-Known Member
I agree, I think they are just covering themselves, I was more curious as to have much I would need in a bigger system. I have emailed Prestone (holts are part of that group) to see if they have any recommendations.
frazion
Active Member
The antifreeze coolant system should be flushed with water. I like to follow that with filling the system with an oxalic acid mix to get rid of any rusty gunk and clean the expansion tanks and running it up to temp before draining, flushing with water and then topping up with a new antifreeze solution. The amount of brown gunk that collects in that system often amazes me.
Andrew M
Well-Known Member
Would Oxalic acid damage any aluminium components in a coolant system , like if you had ally CAC worth several £1000s ?? just a thought........
frazion
Active Member
good thinking, but no, on the acid list its pretty weak (derived from rhubarb) and definitely more so that rydlyme which has an hcl base and a pile of proprietry chemical stuff. just got to make sure that the concentration is made up correctly. then flush with an alkali (bicarb soda). besides, its also in the manual
Fishtigua
Well-Known Member
Don't use anything but water, lots of it. The final flush should be with distilled water as pockets will be left behind. Then fill with the coolant that manufactures recommend.
