S1 Renault Antifreeze Mix

[My S1]

Old topic...once again.  I'm replacing all the rubber cooling/heating hoses and wondering about the proper cooling fluid mix.  Brass radiator, steel tubes and aluminum engine...can I make every part happy?  Not worried about freezing in Nor Cal just concerned about protecting the metals.

[BDA]

Like you, I’m in an area of the country where I don’t have to worry about coolant freezing. I chose to use distilled water and Red Line Water Wetter. That should give better cooling than plain water which provides better cooling than antifreeze and water. Water Wetter has corrosion protection. I change the water and Water Wetter every year.

https://www.redlineoil.com/waterwetter

[My S1]

I'll definitely throw a jug of that into the mix.  Don't believe I want to change it out every year however.  I would feel better with some anti freeze in there.  My main pipes are rusted where the hoses attach on both ends.  fairly badly on the outside but some on the insides as well.  The rest of the length of the pipes appear to be just fine on the outside and it seems as though the rust may not be on the entire length of the pipes internally...but that may be wishful thinking.  Don't know if I want to try and change the pipes out with the engine in place.  A true dilemma.

[BDA]

“Northern California” isn’t very specific, at least for me. Is your car in danger of freezing? If not, there’s no reason for antifreeze.

I’m not trying to tell you what to do. If your car is not in danger of freezing, you don’t need antifreeze. Whether your car might freeze or not, you can get some of the advantages of Water Wetter when using antifreeze but not as much as with plain water.

I don’t change all the water every year. I open up the lower radiator hose at the front of the tranfer tube and drain whatever water will come out. Then I refill with a new bottle of Water Wetter and distilled water. The Red Line tech guy told me to replace the Water Wetter every year to replenish the anti corrosion chemicals. Rather than replacing the water and the Water Wetter, you can probably just add new Water Wetter every year and every other year or so replace the water and Water Wetter.

If you have corrosion in your transfer tubes, you should start planning for new stainless steel tubes.

[DreamsOfA47]

I daily drive an 83 RX7. Not only is the engine a mix of aluminum rotor housings sandwiched between steel end plates with the coolant channels running through that sandwich but the cooling system is also large rubber hoses into a copper/brass radiator. The RX7 forums say that "Asian green" coolant is what is to be used in the rotary engines and it's seems to have been treating my engine well. I've been using the Zerex brand stuff purchased at O'Reilly. Because of its use in my RX7 I also use it in my 1967 S1A Europa. I'm not sure if it'll be of any use but that's my 2 cents.

[jbcollier]

“Antifreeze” also raises the boiling point and contains buffering agents to prevent galvanic corrosion and reduce surface cavitation.  I would run a 50/50 mix no matter how hot it gets where you live.  Where I live, it gets $&@# cold and I run a 60/40 mix.

Water wetter is meant for racing cars where antifreeze is banned due to it being just about as bad as oil when it hits the pavement — dunno why they haven’t banned oil ;-)  Water Wetter absolutely does not contain the same amount of buffering agents as antifreeze so you need to change it often.

I use the “blue” antifreeze from the Volvo/BMW/Porsche/Etc world.  No complaints.

YMMV

[Clifton]

 I've seen enough eroded aluminum from people running straight tap water. Distilled water 50% antifreeze. I'm in Phoenix and it never gets cold.

[My S1]

It sure would have been nice if Lotus ran aluminum transfer tubes and an aluminum radiator.  I've read that the first few off the line used aluminum F2 radiators.