Expansion bottle cleaning

Thanks and well done. I did mine too a few weeks ago while renewing the coolant and inspired by all the posts above. I used 100g of oxalic acid powder, 1/2 litre of warm water and a small handfall of peal barley (i expect rice will work too). Removed the tank from the engine, sealed all the orifices, added the ingredients and shook violently for 10 minutes. Emptied and flushed out being careful to ensure all the pearl barley was out. Excellent result. The pearl barley was added as there was some hard residue at the bottom of the tank that needed some agitation. After and before pictures.
View attachment 102690View attachment 102692View attachment 102691
www.solocoastalsailing.co.uk
Looks great... very similar to my before and after.

Rather than shaking, I just filled mine to the brim and turned upside-down half way through (as there's always some air left).

Don't know why I didn't do it years ago!
 
I ended up soaking the bottle for several days in B&Q brick cleaner, which is hydrochloric acid based. Did the trick perefectly.
Can't imagine the brick cleaner doing any harm to the plastic (as it comes in a plastic container), but I preferred using the Oxalic Acid approach as it's less harsh in general (I think!).

I find brick cleaner does a better job of dissolving organic matter, so use it for that (on the props etc.) and use the Oxalic Acid for pure staining.

Avoid Oxalic Acid on galvanised steel... someone sprayed their boat and the trailer 'chalked' up (didn't do any damage though)
 
Greats great Alt, thanks. I tried buying it a few times but shipping was an issue. The hot water trick is a good tip.
 
Greats great Alt, thanks. I tried buying it a few times but shipping was an issue. The hot water trick is a good tip.
IMO, hot water is the trick. When doing the hull of mine (and others) with a garden sprayer, I find with hot water, the results are instant. As in, the Shannon brown scum you get along the waterline, disappears in seconds (granted, it's not as bad on the Corrib), so you're not worried about wallpaper paste to make it stick.

As mentioned previously, spray with a garden sprayer and walk around the hull. By the time you've done a round trip, it's time for a 2nd spray. Keep spraying until you run out, wash down with fresh water, stand back and admire all the hard work!
 
Thanks for the tip. I bought a boat/garden sprayer last February for spraying Patio Magic on my boat. Great for getting rid of the green slime that takes over in the Irish midland winter. It’s great for the teak decks too.
 
Thanks for the tip. I bought a boat/garden sprayer last February for spraying Patio Magic on my boat. Great for getting rid of the green slime that takes over in the Irish midland winter. It’s great for the teak decks too.
Go on, share the secret re. teak....

I use the usual 2 part stuff annually which works great for half the season.... scared to use Ocalic Acid untl I see reports from someone else...
 
Patio Magic or Borocol is great for teak. It kills all the green on it and you end up with a nice silver teak. I haven’t done any deeper teak cleaning yet but I plan to use a teak cleaner and a treatment. Mix the Patio Magic 4 to 1 with water and spray it all over the boat on a calm dry day.
 
Stick a packet of wallpaper paste in your bucket of Oxalic Acid solution. Stir well and paint on the mixture thickly---the paste allows the Oxalic Acid to remain on the hull rather than running off.
Wait 10 minutes and then wash off with a hose pipe or pressure washer.
 
I'm amazed at some of the elaborate chemicals being suggested above. I cleaned mine this morning so was interested to read this thread.
I just used a sink full of hot water with some floor cleaner (e.g. Flash) and a bottle brush that I use for cleaning the bird feeders.
Took me nearly 10 minutes!
 
I'm amazed at some of the elaborate chemicals being suggested above. I cleaned mine this morning so was interested to read this thread.
I just used a sink full of hot water with some floor cleaner (e.g. Flash) and a bottle brush that I use for cleaning the bird feeders.
Took me nearly 10 minutes!
That is good but there is no way I could clean my VP tank with any sort of brush as there are many ribs/bulkheads, as well as a seperate compartment with some sort of float valve, inside.

www.solocoastalsailing.co.uk
 
That is good but there is no way I could clean my VP tank with any sort of brush as there are many ribs/bulkheads, as well as a seperate compartment with some sort of float valve, inside.

www.solocoastalsailing.co.uk
That sounds like the same as my expansion tank.

I intend a more frequent coolant change service in the future which I hope will make the expansion bottle cleaning easier . The expansion bottle seems to be designed to trap particles etc. and I suspect the cleaning I did is the first time the expansion bottles have been taken off . I hadn't realised how stained the expansion bottles were until I cleaned one and compared it with its partner on the other engine.
 
As Plum said, not a hope you're getting a brush in to the KAD expansion tanks.

My engines are 2003 and this was the first cleaning they got. I change the coolant annually and comes out clean, however there was brown staining from the previous owner. They now look like new and will hopefully stay that way due to my religious annual changing of the coolant.
 
Read this with interest having had two KAD engines boats - cleaned the tanks on the 42‘s with brick acid if memory serves and it did the job. One of the 32’s needed doing but didn’t get round to it as we sold the boat.

Current boat has bespoke stainless steel header tanks fitted remotely from the engines - I think because one engine had the hydronic heating plumbed into the cooling circuit. Just re-done it all and separated the heating from the engine and had to remove the pipe work from the header tanks to the engines to clean them as there was some gunk in them and the tanks. Being stainless, the tanks just needed a flush and wipe.
.
 
Top