Hi everyone!
Fast questions for the pro(s)!
I need to put preston in the radiator.
I have a flathead 239 1946 canadian with an aluminium radiator from champion cooling.
I need to know what type if preston to put in...
There is so many options and aluminium radiator vs steel engine I don't know what to use.
I tried searching old thread but can't find anything.
Thanks in advance!!!

 

In my Camaro I have a 383 (350) cast iron block with a Be Cool aluminum radiator. I run the traditional Green Antifreeze. I have had it in the car for 20 years and no issues. I have changed the coolant twice I think. When I installed it that was what was recommended.

I would be confident with that set up but I am sure others will have an opinion and probably better informed than my anecdotal experience.

 

The coolant bottle should tell you what metals it will protect or isn't compatible with. These old trucks aren't too picky like some of the newer vehicles are. You can go down a rabbit hole reading up on the new coolants and vehicles. Even gasket material is affected by the coolant.

Our old trucks usually had cast iron engine parts and brass/copper radiators, heater cores and T-stats. Now we add aluminum and stainless parts to the mix with our replacement parts. The last jug of the old type coolant I looked at protects all metals. I think it's called universal coolant now,

 

The best coolant is the familiar green ethylene glycol. Here is the the Ford Motorcraft chart for their coolant recommendations. Since all we deal with are pre-1999 classics, you can ignore most of this chart. Go straight to page 2 and look at the pre-1999 column. Page 4 gives you the specs on the various coolants listed. Yours will be on the far left hand side of Page 4.
https://www.motorcraft.com/content/d...ts_english.pdf

The Motorcraft site will give you the specs for the recommended coolant that you can then convert to whichever brand you want to use.

If you choose a concentrated coolant that needs to be diluted, make sure you only dilute with distilled water and do not use tap water and or bottled drinking water. The minerals in tap water are not good for the coolant.