Hi All

Came across this article in a motoring journal

ELECTROLYSIS CORROSION
Electrolysis Corrosion (EC), or “stray current corrosion”, is a cause of cooling system failure.

What are the issues for identification, prevention and cure?

Identification: The primary indicators for Electrolysis Corrosion are:

Failure: A blackness will be evident on the radiator header plate below the inlet manifold.

Residue: Deposits of Aluminium Hydroxide build up on the core internals. This usually appears as grey or brownish residue, soft to touch, built up as a coating on the inside of plastic parts, particularly on the inlet neck.

Pitting. Aluminium surfaces take on an orange peel effect. Pitting occurs at point contact zones of weakness.

Other indicators. Acidic coolant, residual voltage difference between coolant and earth with all electrical circuits off, and discoloration of copper or brass oil coolers — usually causing blackening.

Cause: E.C. is most often caused by the passage of electrical current through the coolant. This arises because a voltage potential difference can be set up between the engine block (which is held very closely to Earth Potential) and the radiator body (which may be at a floating Earth Potential).

A floating Earth Potential arises when the nominal Earth return path in an electrical circuit is affected by high resistance such as dirty connectors or paint between recently replaced body panels. A consequence is that the radiator/coolant/engine block path may represent a parallel path of relatively low resistance in which stray current can flow.

Interestingly, E.C. rarely affects vehicles fitted with dedicated Earth return circuits in their wiring systems.

This is what I included into my electrical upgrade for the third Gens

Also, make sure that the coolant is serviced regularly, as I understand that there is only a thin layer of metal in the lower radiator, separating the coolant from the 'oil cooler'

Any perforation of this thin layer due to corrosion would of course be catastrophic.

Cheers, Barry

Electrolytic corrosion is nothing new - it is caused by the use of dissimilar metals in an electrolyte creating a potential difference (current).

"A consequence is that the radiator/coolant/engine block path may represent a parallel path of relatively low resistance in which stray current can flow."

Relatively low resistance? OK. If you have ANY current flowing through this path you have some major earthing issues. You wouldn't be able to crank the engine! Since the block is at ground (negative) potential, and the starter motor relies on this as its return, you would have starting problems (from a high resistance joint) long before you would have corrosion issues) The higher the current across the resistance, the greater the potential difference across each end of the resistance. At very high currents, you would have (at most) a maximum of 3-5V drop (this includes across the coolant), or the engine would not crank.

At steady state (running) across this resistance, you would have next to NO current flowing. With the engine off - there is no power to anything (or your battery would die quickly) so NO current flows at all.

"Residual voltage difference between coolant and earth with all electrical circuits off" Once again - probably from acidic coolant (ie. coolant without corrosion inhibitor or plain water used). If you have this (measurable voltage) between radator and block, then you have acidic coolant AND an unearthed radiator."

Earthing upgrades really, really are a waste of time unless you have some major issues with starting, dim headlights etc. If you are concerned, measure the voltages between the earth point and the battery.

Look at all of the 'earth upgrade' kits on ebay - words like civic, ralliart, wow and +5bhp feature heavily in these advertisments. Have a think about this...

Cheers
Heath Young

So Tell Me Why They Are Still Using Coolant And Not Just Water

Because - it boils at a temperature higher than water, it freezes at a temperature lower than water and it has anti-corrosive additives.

Cheers
Heath Young

Because - it boils at a temperature higher than water, it freezes at a temperature lower than water and it has anti-corrosive additives.

Cheers
Heath Young

THE COOLING SYSTEM FANS THERMOSTATE AND RAD CAP CONTROL BOILING

IN QLD WATER DOESNT FREEZE

MOST COOLANTS ARE ACIDY AND CAUSE THE ALLOY TO GET EATEN

ALLOY HEAD
COOLANT
CAST BLOCK
=
BATTERY

errrmmm water is actually slighty acidic (ph of roughly 7.5) and if you just had water as a coolant it would eat away the alloy quicker due to oxidization. Someone correct me if i'm wrong, but I thought that coolant was also a corrosion inhibiter as well

More kits on the way Barry?

Still waiting for you to reply to my PMs about the lean out kits, or are you just ignoring me?

Hi all,
Just thought some members would like to have a read of the following article. It has been posted on AMC before but i couldn't find the old thread.
I noticed a big difference after installing my Earthing kit.

More kits on the way Barry?

Still waiting for you to reply to my PMs about the lean out kits, or are you just ignoring me?

Sorry phonic - I would never intentionally ignore anyone
I have one of your original PMs marked as answered - still awaiting your reply, so I'll re-send that first thing

Cheers, Buddy

errrmmm water is actually slighty acidic (ph of roughly 7.5) and if you just had water as a coolant it would eat away the alloy quicker due to oxidization. Someone correct me if i'm wrong, but I thought that coolant was also a corrosion inhibiter as well

yea but water doesnt burn your skin coolant does

alloy boats are in salt water all the time doesnt seam to affect them

ever noticed boats run a positive and a negitive wire to all lights and switches(no earth to boats body)

this is because if you were to earth the alloy boat and use it on salt water it wouldnt last long due to the electrons moving through the alloy. just like a batterys lead eventualy gets eaten away

yea but water doesnt burn your skin coolant does


Burn? Only when it is hot? :nuts: Coolant is water with 10-30% Ethylene glycol (which is poisonous when ingested in large enough quantities - think 300mls pure). It is sweet to the taste and smell, and is very occasionally used in food - hell, the French were putting it in their wine - only way to make it taste any good. The anti-corrosive additives are not acidic.



alloy boats are in salt water all the time doesnt seam to affect them

ever noticed boats run a positive and a negitive wire to all lights and switches(no earth to boats body)


They are aluminium, and anodised. The anodising protects the aluminium from corrosion (although where scratched/drilled corrosion can occur, the 'self healing' properties of aluminium do not apply to salt water environments).

The downside of anodising is that it is an electrical insulator (hence why you run a negative wire to all lights and switches) and some alloys are poor electrical conductors (whereas the iron body of a car is a good conductor).



this is because if you were to earth the alloy boat and use it on salt water it wouldnt last long due to the electrons moving through the alloy. just like a batterys lead eventualy gets eaten away

That's a load of horse pucky. There is no way that the electrons would 'move through the alloy'. You can use what is known as a passive or active sacrificial anode - a metal that is more reactive than what it is protecting (passive - for example, magnesium for aluminium) or the same metal (active - a voltage is placed on it) to deliberatly 'move electrons through the alloy' but to protect it (where dissimilar metals have been used).

This method is also commonly used for things like protecting bridges/piers made of metal - you chuck a wire onto the metal of the piers, throw an old engine block or head into the salt water with a wire attached, and hook up the wires to a low voltage current limited power supply. Result? The engine block rusts away in record time whilst the pier is untouched. Dead engine blocks are cheap, electricity is cheap, replacing metal underwater isn't.

The battery's lead does not get eaten away, it migrates (to the other electrode). Car batteries die from sulphation (it shorts the plates). It migrates back to where it came from when it is charged.

I seriously suggest reading up on sacrificial anodes, electrolytic corrosion, anodising, marine and automotive electrical systems before replying... Hell, read up on some basic physics/chemistry!

Cheers
Heath Young

Electrolytic corrosion is nothing new - it is caused by the use of dissimilar metals in an electrolyte creating a potential difference (current).

"A consequence is that the radiator/coolant/engine block path may represent a parallel path of relatively low resistance in which stray current can flow."

Relatively low resistance? OK. If you have ANY current flowing through this path you have some major earthing issues. You wouldn't be able to crank the engine! Since the block is at ground (negative) potential, and the starter motor relies on this as its return, you would have starting problems (from a high resistance joint) long before you would have corrosion issues) The higher the current across the resistance, the greater the potential difference across each end of the resistance. At very high currents, you would have (at most) a maximum of 3-5V drop (this includes across the coolant), or the engine would not crank.

At steady state (running) across this resistance, you would have next to NO current flowing. With the engine off - there is no power to anything (or your battery would die quickly) so NO current flows at all.

"Residual voltage difference between coolant and earth with all electrical circuits off" Once again - probably from acidic coolant (ie. coolant without corrosion inhibitor or plain water used). If you have this (measurable voltage) between radator and block, then you have acidic coolant AND an unearthed radiator."

Earthing upgrades really, really are a waste of time unless you have some major issues with starting, dim headlights etc. If you are concerned, measure the voltages between the earth point and the battery.

Look at all of the 'earth upgrade' kits on ebay - words like civic, ralliart, wow and +5bhp feature heavily in these advertisments. Have a think about this...

Cheers
Heath Young


Hi Heath

Thanks for all the effort you have put into this subject
I often find your posts an interesting and worthwhile read

The original article was from a Trade journal with many years of credibility, and I'm sure they have published it to help car owners anticipate cooling system problems, rather than see them have expensive failures down the track.

Owners can solve most of the problems you mention by earthing the cooling system, but it must be done carefully.


Earthing upgrades really, really are a waste of time unless you have some major issues with starting, dim headlights etc. If you are concerned, measure the voltages between the earth point and the battery.

Look at all of the 'earth upgrade' kits on ebay - words like civic, ralliart, wow and +5bhp feature heavily in these advertisments. Have a think about this...

I have done some research which tends to disagree with you here
For many years, Japanese race and rally teams dominated with their use of efficient grounding systems to extract more power from their electrical and ignition grounding systems.

You might also have read the "performance buildups" article by now where they gained 5-7Kw on a V6 Magna with only a standard grounding system

Yes, I would be careful about buying untried wiring kits on Ebay. However, for info there is a local source at http://www.hotearth.com.au/

The problem is that these kits are 'way over the top' with oversized cable that can be cut too short or too long, bright colours, expensive, and can make the engine bay look like "a jungle" of messy cables. They may be more suited to 4 Cylinder cars, and have usually an insufficient number of connection points to properly suit the V6 Magna

There are actually 3 weak electrical points in the 3rd Gens. I've found if you fix these points and then also install a correctly designed integrated earthing system, large increases in Torque and improved driveability can be achieved

I will be posting more info on a custom Earth/ground tuning DIY Kit soon

Cheers, Barry

Sorry phonic - I would never intentionally ignore anyone
I have one of your original PMs marked as answered - still awaiting your reply, so I'll re-send that first thing

Cheers, Buddy

No worrie,

I have accually sent you 2 PM's since the 1st.

I will have to track down the performance buildups article - IIRC someone posted it here? a while ago but I couldn''t find it. Interesting...

Cheers
Heath Young

I will have to track down the performance buildups article - IIRC someone posted it here? a while ago but I couldn''t find it. Interesting...

Cheers
Heath Young

http://www.aussiemagna.com/forums/showpost.php?p=457939&postcount=8

Cheers, Barry

I'm still not sold on the idea of buying an earthing kit especially at the prices that they sell for. If I really wanted to do this I'd just grab a whole load of 4 gauge wire and hook the stuff up. It would be interesting though to actually get someone from AMC to do some before and after dyno's if they were going to do this.