I just got my radiator from ron davis radiators. I noticed all the fittings/sending unit for fan were either aluminum or stainless. There is a tag on the overflow port that says to avoid using brass in the cooling system because it promotes electrolysis. It also states that in the attached instructions.

I have brass freeze plugs,robert shaw thermostat has brass, and sensing bulb for autometer temp gauge is brass. Will it be okay?

It is my new motor with alum. heads,intake, very expensive radiator :0) etc...and I want to make sure I do it right.

Here are some pics of radiator on lateral g website.

http://www.lateral-g.net/gulbranson/motor/rondavis3.jpg

http://www.lateral-g.net/gulbranson/motor/rondavis2.jpg


http://www.lateral-g.net/gulbranson/motor/rondavis1.jpg
Thanks, Ray

make sure you have GOOD engine grounds and a ground off the radiator ( if it is shock mounted)

good ground for the engine is the frame then frame to body.
I also use distilled water and glycol mix in my radiator which hinders electrolysis.

The key to electrolysis is keeping the coolant from becoming a good conductor regardless of the metals involved. This is done in many ways.

Here is a good article on the "galvanic" problems in a cooling system... http://www.popularmechanics.com/automotive/sub_care_clinic/1363277.html

thats why i mentioned the ground straps and distilled water.

Nice fabrication, but incredibly poor design - about 40% of the airflow through the core is blocked, and it has no pressure-relief flaps to open the sealed shroud for added highway-speed cooling airflow either. These people are cooling "experts"? :(

John,
Just curious why you say that ? It looks like the fans are "lifted" off the face of the radiator about an inch, so even though all of the air has to go through the fan openings, it will indeed flow through the entire radiator. No different than a normal shroud ? Allows the fans to draw air through the entire surface area of the radiator also. Looks pretty good to me, but I am not a cooling system specialist by any means.

Bill, I think John's point is the problem with airflow is not the position of the fans but the proximity and area of coverage of the plate on the back of the radiator. At high speed there will be a high pressure area on the face of the plate because of the cumbersome route the air must make to exit the fan openings and the difference in area of the inlet/exit leading to a reduction in flow in the portions coverd by the plate. It does look nice.

Thanks for the input guys. I spoke to Tim at Ron Davis about not having the hinged relief flaps (like be-cool has) in the areas where there is no fan opening. I was concerned about restricted air flow at freeway speeds. He said they do add flaps to systems that require it ( he had some calculation 4" times this, air space times that or something like that)

He assured me that I would not have that problem with this setup. The aluminum shroud is NOT pressed up against the fins. There is ample room for air to flow out, especially when freeway speed air is being forced in.

By the way I was really considering the be-cool setup, they have one similar to this (except the becool has 1" tubes while this Ron Davis has 1.25" tubes)

Thanks for the input, Ray

Now to get back to my electrolysis post. I was checking the voltage per instructions. It says to hook negative lead to neg. batt post and positive lead in coolant just touching coolant and nothing else. paper work says zero to .3V is acceptable for cast iron engines.Also states ".5V will destroy the engine over time" and "engine manufacturers are reporting .15V will destroy an aluminum engine"

I am getting .41V w/eng running. It is not a grounding problem my car has a ton of ground wires. I even have a 7ga cable from negative battery post to radiator itself. The instructions say to replace the coolant to remedy this problem.

I am using the new 50/50 green prestone ( It is 30 minutes old LOL!) Now I'm wondering if this new premix is the same quality as the original prestone. Or is the old stuff with distilled water better?


Thanks again, Ray

Regardless of performance, that is the nicest radiator/shroud I have ever seen!

http://rotometals.com/pencil.htm
click on this link
you could put a sacrificial anode in your radiator
WHY this works, now I know. We have been studying redox reactions in Chemistry and learned about the Activity Series. It’s a series of elements arranged by their ability or willingness to lose electrons (reduction). The higher the metal is in the series, the more readily they will react with hydrogen, oxygen, water, etc.

What does that mean? If you were to bolt a metal higher in the series than Iron to your car, it will lose electrons before the iron body does and therefore, erode before the body rusts. Some of the metals you could use as a sacr. anode: Magnesium, Aluminum, Manganese, Zinc, or Chromium. The best elements to use, magnesium and aluminum. That got me thinking, I guess if you put an aluminum radiator in your car, it has become the sacrificial anode. The radiator will corrode before the body does.

It used to be with small aluminum parts in the cooling system (such as water necks and even just aluminum water pumps) that they COULD become the "sacrificial" anode so to speak with limited surface areas....but when you put a large surface such as a radiator and heads and pumps all in....the surface area is so large to give up (to electrolysis) electrons....that sacrificial anodes are really not necessary.

Also to the point of one poster....make sure not only the engine is grounded....but the radiator is as well. I have seen powder coated parts become insulation for radiators and literally electrically "float" the part creating large voltage readings.

I use only G05 type coolants with aluminum.

What if one where to "electrically isolate" the radiator to the support?

Don't forget to run a separate ground line back to the frame for the fans.

You can't electrically isolate a radiator. You could, up until you put coolant in the car, coolant is conductive. And don't keep an eye out for coolant that isn't. Anything that is thermally conductive will be electrically conductive, they both depend predominantly on the electrons and orbital arrangements at the elemental level...at the compound or aqueous solution level these properties then include the bonding properties (ionic, covalent, metallic) which is still dependent on the orbitals but atomic radius and other properties come into play a little more.

You can't totally stop electrolytic corrosion (EC). (The Redox poster could back me up on this and my previous comment.)

Don't worry too much, any 2 disimilar metals will have some level of EC. If you have grounded your Rad, the only additional thing you might want to do is use an anti-corrosion compound or an extremely thin layer of teflon tape (if you can still get the seating torque.)

Be a little leery of your meter readings when you are measuring anything below 1.5V. If it sin't a Fluke that is new and/or calibrated or another top brand it simply isn't reliable (I fought wars that were never declared over this.)

The comment on the size of that Al Rad is right it is so large that any difference in potential should be spread over such a large surface that there should be little sacrificing.

Do the obvious things and check your fittings next year when you do a drain and flush.