Ron Davis Radiators

[Scrrem]

For those running Ron Davis Radiators...I was doing some work at a friends house yesterday when the question came up...why don't I have a drain petock on my Ron Davis radiator? I can't locate the documentaiton that came with my radiator, but I seem to recall it saying that brass and aluminum don't work and play well together and the plug should only be aluminum. Can anyone else chime in here?
Rich

[secondchance]

Rich,

Different metals, especially in presence of electrolyte (i.e. coolant) will result in corrosion.
"when two or more (metals) come into contact in an electrolyte, one metal acts as anode (http://en.wikipedia.org/wiki/Anode) and the other as cathode (http://en.wikipedia.org/wiki/Cathode)".

Some of our throttle bodies bubbling finish around the top plate is due to same scenario.

http://en.wikipedia.org/wiki/Galvanic_corrosion

[WVZR-1]

Ron Davis actually in their install instructions actually has continuity tests that they suggest using to confirm the continuity of the cooling system and the coolant.

http://www.rondavisradiators.com/tech.htm

I believe that a petcock if desired from Ron Davis is an "add-on" to the build. Most later OE petcocks weren't of brass construction either. Most are a composite product. I would think having a petcock added to the radiator wouldn't be terrible nuisance if you wanted.

GM quit building OE radiators with drain-cocks in '01 or so and an over the counter replacement will NOT have a petcock even if the OE did. I would guess a suction device for evacuating the coolant is the desired method.

[Scrrem]

Thanks Dave, Yeah I guess I need to look for a plastic petcock if I want to add one, because ones made out of brass are a no-no on all aluminum radiators.
Rich