Applying all of this I:
o Installed a tank, from a Chryco type of car, behind the driver's side headlight
o Installed Volvo fan
o Built a full surround rad shroud with blades properly exposed.
o Opened up the bottom Valence by wire edging
o Installed a new three core rad and checked the fins
With this set-up my TIGER has towed a small tent trailer, fully loaded, through traffic and up mountain passes in 110°F weather with no overheating.
Air-flow through original shroud
Air-flow with Custom Fan Shroud
Coolant
When Dennis had his MG engine finished it cooked as soon as it was started and warmed up. The Engine man tore it down and found crystals of goo everywhere. He blamed the machine shop for not cleaning out the caustic soda after boiling the block. They denied this and said that it was something that he had done.
I was asked to have the college Physics Department do an analysis of the gunk. They did a spectroscopic (or some such analysis) as well as other tests and came up with the answer - Mineral Salts. Dennis had insisted that the rebuild shop use distilled water to fill the system. The supplier of the bottled water delivered mineral water in error. The Chem folks told me that antifreeze is "designed to bond" to the minerals in the water of a car's cooling system. The catalyst for this reaction is heat. In Dennis's engine the heat caused the minerals and the antifreeze to bond but there were too many minerals and they precipitated out, as "gunk", causing more heating, which caused more precipitated crystals, which caused more heat, etc.
Distilled water has no minerals. The Chem types say most antifreeze should be used with TAP water. If there are no minerals in the water, the antifreeze bonds to the minerals in the block and, in effect, breaks down or, more accurately, does not mix as it should. Not a good thing if this is true!
Pure antifreeze will not cool properly, nor will straight water. Mixing the two is more than just diluting the antifreeze. A chemical reaction takes place. They went further to say that anti freeze should be measured and then mixed outside of the engine (away from the catalyst of heat) and in a plastic container, just as you would mix oil and gas for a two stroke before pouring it into the tank.
When I told all of this to Dennis he tried distilled water with antifreeze and then tap water with antifreeze, as an experiment, and says there was no difference in cooling his over heating 1275 hot rod Mini. (A larger rad from an Austin 1100 fixed this one.) He still swears by distilled water, though, regardless of what the chemists say. Handbooks, for some cars with aluminum engines, advise the use of distilled water. Most say nothing one way or the other.
I think it may be a long-term thing but perhaps it would be best to check the antifreeze manufacturer's spec before using distilled water. I only repeat what I am told on this and personally shall continue to mix tap water with the coolant, as I have done for many years and Dennis shall continue to use distilled. And the Chem guys? They as so nerdy they probably never check their oil talk about their antifreeze.
**
