galvanic corrosion in automotive coolant system
galvanic corrosion in automotive coolant system
(OP)
I have been having some issues with galvanic corrosion in a coolant system of a race car (operating at approx. 120°C and 4bar), this causes problems of increasing coolant pressure due to the production of hydrogen gas in the system (accumulated gas made a pop sound when touched with a lighted match). The radiators are aluminium and there are other materials including steel in the system and a potential difference have been measured between different parts of the system. My next step is to get the coolant analysed for aluminium content after use to confirm whether it is the radiators corroding.
Changes to different coolant additives have not been successful. My colleagues are now keen to place 'earthing' straps between the different areas, however I not believe improving conductivity is the correct approach and in reality the opposite should be done, ie isolate each area.
Advice on the best way to go would be appreciated, as would any other ideas or comments.
Changes to different coolant additives have not been successful. My colleagues are now keen to place 'earthing' straps between the different areas, however I not believe improving conductivity is the correct approach and in reality the opposite should be done, ie isolate each area.
Advice on the best way to go would be appreciated, as would any other ideas or comments.





RE: galvanic corrosion in automotive coolant system
RE: galvanic corrosion in automotive coolant system
Have you looked at molybdate inhibitors? They are the least environmentally sensitive ones out there but they are very good in mixed metal systems.
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Plymouth Tube
RE: galvanic corrosion in automotive coolant system
RE: galvanic corrosion in automotive coolant system
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: galvanic corrosion in automotive coolant system
Over many years, the only galvanic problem I have seen is when the idiots at GM put on small aluminum fitting (intake manifold, water out ,elbow) into a system that was otherwise all cast iron /copper.
RE: galvanic corrosion in automotive coolant system
RE: galvanic corrosion in automotive coolant system
Are you using a commercial coolant? (Prestone II) If not, then why not?
My hunch is that this system has some different metals connected to each other that they cannot avoid. Isolating each metal from the others will keep this from happening.
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Plymouth Tube
RE: galvanic corrosion in automotive coolant system
You're going to have significant corrosion problems if you don't have an inhibitor package. I'd go to some of the coolant companies and see if they have a specialty high temp/performance version of their product.