ERPS Electronic rust prevention

Thanks Gerry, I think the article is about Cathodic "Zinc anode" protection mainly used in boats that are on the water full time. I am led to believe that ERPS is a different system. I will wait and see what others have to say.
Cheers and Merry X-Mas & a Happy New Year.
Drive carefully

George, I think that if you read that item again you will note that it explains how and why the corrosion takes place. It also sugests that there are some items on the market that may not work. So, if you know the science then you can read a manufacturers publicity material and make an informed descision on the merits of the system being marketed.

Hows it going George ,

Was involved in a disscussion about a week ago on this topic .

As Kiwi says , have a closer look at the link , Its written by Dr Karl .

I was paricularly interested in the part about these units being banned in the US ( thats got to set off warning bells ).

Glenn.

Hi George,
Further to my earlier post, some earlier devices were described as "electronic cathodic protection" or similar. I think this description has disappeared now. As Dr Karl states in the article, cathodic protection only works where moisture is involved and only at the point of galvanic contact. My experience with non-marine cathodic protection involved buried steel containers, which had zinc bars buried in the ground and wired back to the steel container. In this case, moisture in the ground completed the electrical circuit.
Having read the technical jargon of a couple of ERPS units which have patches with an applied voltage which spreads protective electrons in a field stretching some distance from the patch, I fail to see how the electron field can reach enclosed areas such as rocker panels, usually the area of much rust in vehicles. Back in the mid 1800's, Faraday showed that the interior of an enclosed metal container will be completely isolated from an external electric field, from which one can draw similar parallels with the rocker panel or other fully-enclosed body sections. Unless these are cut open and a patch inserted, then they will remain unprotected.
I have never owned one of these devices; my technical background has shied me away from their explanations, so I have never tested one. I did, though, own a bog-standard Mav for 12 years, which included a lot of beach runs, incl through salt water. Each time I washed the body and underside in a timely manner. The vehicle was still rust-free when I sold it. My current Patrol is nearly 7 years old, and despite beach runs, is still rust-free (had the door panels off recently to check). I put this down to modern vehicles being better primed and treated from new.
The only rust mod I have done to the Nissan is to spray some fish oil into the door panels, rocker panels and wherever I think rust might start.
I have found that the fish oil also seems to stop the spread of existing rust (I used it to some effect on a 70's Italian car I once owned, which you could hear rusting, if you stood perfectly still and listened)
Gerry

I have found that the fish oil also seems to stop the spread of existing rust (I used it to some effect on a 70's Italian car I once owned, which you could hear rusting, if you stood perfectly still and listened)

Gotta love the old Alfa 33/Alfasuds.....

I had a sud, stoped at a set of light went to go and the front suspension broke in half, still the most fun I ever hade in a car.

Have fun
Craig

Funniest I heard was a guy that was sitting at a set of lights in a Sud, and felt (and saw) his car sink. Thinking he had a flat tyre he got out, only to find the floor pan and body behind the front seat had parted company across the width of the vehicle (think chainsaw attack to the floorpan and rocker panels...). The only thing holding the vehicle together was the upper part of the side panels and roof.

Actually, it was a Fiat BC-series 124 Sport. Not as bad as the Alfa Suds for rusting, but it still rusted. Fabulous car otherwise. Only sold it last year - had it since 71.
Memories......