Heater Matrix and Electrolytic Corrosion

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Rhothgar
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Heater Matrix and Electrolytic Corrosion

Post by Rhothgar »

I was talking with a mate about Sylv's the other day who tinkers with Citroens and he said it has probably blown a hole in the heater matrix through electrolytic corrosion.

Obviously, ships use a block of zinc bolted to the hull to prevent it. Do Citroens have a 'less noble' metal bolted somewhere or wired in to act as a sacrifical lamb.

It never really occurred to me but a colling system is like a ship inside out - the water being contained rather than outside.

It is only 2 years since I replaced Sylv's heater matrix and being upset at the thought of having to replace it again is an understatement.

Off to Austria tomorrow to bring the car home to England.

The thought did cross my mind about changing it whilst over there but we have no tools over there and I cannot remember what I would require.

Screwdrivers and Philips are the obvious ones and a T27 to remove the steering wheel ABS unit. That's all I can remember. Would anyone like to add to this list to tempt me into trying to do the job over there?

We found a factors in Vienna who sell heater matrix for 12 Euros!!! They sell Valeo for 42 Euros so Valeo it is. I ain't risking a non-genuine part this time.
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Stickyfinger
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Re: Heater Matrix and Electrolytic Corrosion

Post by Stickyfinger »

No it is not like a ship as the cooling system is (should be) protected by additives in the Antifreeze to prevent it corroding. These De-Oxygenate the water and balance the PH to protect. Glycol and such is a poor conductor.

I know two race teams that run with distilled water and Fernox Central Heating additives, F1 protector and pump lubracant
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Re: Heater Matrix and Electrolytic Corrosion

Post by Rhothgar »

I appreciate that antifreeze is there o stop corrosion but I just wondered if it was bolstered in some way
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myglaren
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Re: Heater Matrix and Electrolytic Corrosion

Post by myglaren »

When you do it Roger, add a bottle of Forte Cooling System Stop Leak
If I am not mistaken, Valeo insist on this if their warranty is to be valid.
It contains anti-corrosion and lubricating products over and above those in the standard antifreeze.
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Stickyfinger
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Re: Heater Matrix and Electrolytic Corrosion

Post by Stickyfinger »

Rhothgar wrote:I appreciate that antifreeze is there o stop corrosion but I just wondered if it was bolstered in some way
Good Anti Freeze does have these additives, cheep well your guessing as the "standards" are based on the temperature protection levels NOT the corrosion inhibiting properties.

At the next service I will be using Fernox products.......but that is a personal choice and I use them every day in massively expensive installations, a standard OM brand such as BMW/Citroen/Pug etc is already loaded but NEVER dilute it.
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Re: Heater Matrix and Electrolytic Corrosion

Post by Rhothgar »

I once know a guy that ran 100% antifreeze in his tuned up Herald 13/60
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Re: Heater Matrix and Electrolytic Corrosion

Post by Stickyfinger »

Rhothgar wrote:I once know a guy that ran 100% antifreeze in his tuned up Herald 13/60
Yep quite common in its day, with the new "wetting" agent additives there is a better heat transfer to water these days....
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Re: Heater Matrix and Electrolytic Corrosion

Post by KP »

To be honest some places run 100% in truck units.

To be honest if you use good stuff and ratio it with distilled water and to protect down -50'c should do it fine just flush the system before fitting with a hose to get any fine particles out which is the crux of the issue as they just wear down the thin walls of the matrix :(
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Re: Heater Matrix and Electrolytic Corrosion

Post by Rhothgar »

Well! Well! Well!

in my seeming never endless research on this on the internet, I found myself back on FCF on a post by Alan S which links to a now invalid guide. if thread is not locked, I will upload correct link as obviously Tectaloy have played around with their website since Alan posted this way back in 2006.

Unbelievably, it states that the coolant can become charged and this is one reason why systems can corrode so quickly.

So I tested Sylv's coolant and it registered 72mV.

Will flush before we drive back to UK and refill.

An interesting bit of research.

from what I have learned, I am considering having a heater matrix made of copper for Sylv's car. i think a man should not have to ever suffer more than one matrix change in a car's life, let alone TWO!
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Post by addo »

I see it as the ten-yearly full scrubout and de-moulding of the heater box and ducting. Good for your health overall.
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Re: Heater Matrix and Electrolytic Corrosion

Post by Old-Guy »

Unfortunately, Forte won't sell direct to 'consumers' - only through selected garages; all those nearest me are some miles away and a completely unknown quantity. I'd rather forgo Forte than have some apprentice filling up the cooling system with an expensive but indeterminate mixture of unspecified 'anti-freeze' and tap-water laden with sodium, calcium, suphate, phosphate, nitrate and carbonate ions. And of course, it would be hard to tell if the job had been done at all, let alone if Forte had been added (other than to the bill).

I prefer to drain the cooling system myself, re-filling with my own 50/50 blend of good quality anti-freeze and distilled water (from dehumidifiers). Either way, I end up doing the tedious technical part of the job, bleeding the cooling system carefully and thoroughly.
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Re: Heater Matrix and Electrolytic Corrosion

Post by Rhothgar »

I only did it last exactly 2 years ago Addo.

I have a friend with a garage so I can get Forte no problem. Which one do I need for Citroen TD 1997, Old-Guy?
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Re: Heater Matrix and Electrolytic Corrosion

Post by Xantidote »

Rhothgar wrote:I am considering having a heater matrix made of copper for Sylv's car
So what is a matrix made of? Never bothered to check when I did the matrix on my Xantia
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myglaren
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Re: Heater Matrix and Electrolytic Corrosion

Post by myglaren »

Old-Guy wrote:Unfortunately, Forte won't sell direct to 'consumers' - only through selected garages; all those nearest me are some miles away and a completely unknown quantity. I'd rather forgo Forte than have some apprentice filling up the cooling system with an expensive but indeterminate mixture of unspecified 'anti-freeze' and tap-water laden with sodium, calcium, suphate, phosphate, nitrate and carbonate ions. And of course, it would be hard to tell if the job had been done at all, let alone if Forte had been added (other than to the bill).

I prefer to drain the cooling system myself, re-filling with my own 50/50 blend of good quality anti-freeze and distilled water (from dehumidifiers). Either way, I end up doing the tedious technical part of the job, bleeding the cooling system carefully and thoroughly.
Some factors sell it - my local car place is associated with a workshop so he can sell it.
There's another repair shop that sells a few parts and it can be bought over the counter there.
It is also available from eBay.
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Re: Heater Matrix and Electrolytic Corrosion

Post by Rhothgar »

Matrix is made of toffee. It performs identical to one made from aluminium.

Toffee shares the element number as aluminium.