[Amel] Re: How to acid clean sea water intercoolers

seafeverofcuan <seafeverofcuan@...>

Dear Eric and Gary,
I have the greatest respect for your input and it has saved me many hours of frustration and work. But, PLEASE do not bring "On Off" onboard your vessel. The slightest leak and you will oxidise every piece of mild steel on board.
I stupidly left a 5 litre container inside a rubber bucket and stored it in the port side locker. It leaked and vaporised.

Net result, central heat duct pipes a mess with rust, all regulators, exposed wiring, bolts and the steering chain for the autopilot seized solid, so that continuous boiling in oil would not free and I had to replace the chain - NEVER AGAIN!
Within seconds of using it on the hull you will feel the heat increase in your hands.
Please take care with that product.
Best wishes.

--- In amelyachtowners@yahoogroups.com, amelliahona <no_reply@...> wrote:


According to the MSDS (Material Safety Data Sheet) On & Off is composed of the following by weight:

20-25 % Hydrochloric Acid
5-10 % Phosphoric Acid
1-5 % Oxalic Acid, dihydrate
1-5 % Ethoxylated nonylphenol
60-65 % Water

The advertising for the product states emphatically that is is safe for fiberglass and in fact it states that it's primary mission is for use on fiberglass.

Guess I will have to give it a try.


--- In amelyachtowners@yahoogroups.com, kimberlite <kimberlite@> wrote:


Isn't on/off muriatic/hydrochloric acid---sure smells like it.

Fair Winds


Kimberlite Super Maramu #376


From: amelyachtowners@yahoogroups.com
[mailto:amelyachtowners@yahoogroups.com] On Behalf Of amelliahona
Sent: Wednesday, June 12, 2013 8:30 AM
To: amelyachtowners@yahoogroups.com
Subject: [Amel] Re: How to acid clean sea water intercoolers


That is very helpful. Thanks for the On-Off info. I will look into it. When
used as a hull cleaner does it etch the gelcoat at all?

Which Yanmar heat heat exchanger did you clean? Was it the fresh water to
sea water exchanger, the seawater to engine oil exchanger, or the sea water
to transmission fluid exchanger?

I know that the Yanmar sear water to fresh water heat exchanger tubular core
is a separate part from the housing in which it sits. Can you elaborate on
the removal process/difficulty if indeed you have done that?

Thanks for all your help.


--- In amelyachtowners@yahoogroups.com
<mailto:amelyachtowners%40yahoogroups.com> , "Judy and Bill aboard SV BeBe"
<yahoogroups@> wrote:


I was in New Zealand and could not buy acid because it requires a special
license...I had a marine engineering shop do it for me.

However, I did acid-wash the heat exchanger core on the Yanmar using
On-Off which is a combo of hydrochloric, oxalic and phosphoric acids. I let
the heat exchanger core soak in the On-Off for about 5-10 minutes until it
was visibly clean. I then rinsed it with fresh water and soaked it in a
bucket of baking soda and water to neutralize any residual acid.

A side note about On-Off: On-Off is advertised as a hull cleaner, but is
also an excellent metal cleaner and rust remover. DO NOT USE it on chrome
plated turnbuckles or chrome plated winches as it will remove the chrome.

Hope this helps.

BeBe SM2k, #387

[Non-text portions of this message have been removed]

Join main@AmelYachtOwners.groups.io to automatically receive all group messages.