Hello all
what coolant don’t guys use on these engines
I’ve always used the green stuff Prestone

wondering if it’s ok on these engines ?
I have a 455 bored .30 over with all the goodies

 

For the Olds I use the generic ethylene glycol from the local parts store or wherever has the best price. Last time was the Safeway store that had it marked down 50% for clearance.

 

The green stuff.

 

I tend to use Prestone. Been using it since I bought my '72 U code Supreme 6+ years ago and it's done well for me.

 

I've been using green Prestone in my Oldsmobiles since 1974. There was no option then.

 

You guys using pre-mix or distilled/de-mineralized water?

 

I mix my own with tap water, the water here is not that hard.

 

Zerex has been around forever and is as good as Prestone. It also comes in orange or green. Prestone is more common.

 

Pre-mix is a tax on people who are bad at math.

And I've been using tap water since 1974 with zero issues.

 

Don't do that with New Mexico water. That **** has so much calcium it will ruin a Mr Coffee in 3 months!

 

I've never lived in NM. In any case, a gallon of distilled costs a couple of bucks. That plus a gallon of full strength nets two gallons of coolant for a fraction of the cost of two gallons of premix.

 

Exactly what I did when I lived there. Just a general warning...

 

Yeah, our well water took down three water heaters in five years.

 

I use green in the old cars. Full strength and use distilled water, We have hard water here. I use universal coolant in my Alero.

Pat

 

Just went through this on 2 455’s this summer. In my part of CA we don’t get snow, so I use 70% distilled water (cheap insurance), 30% green stuff and 2 bottles of water wetter.

If you get snow, put the mix up to 50% antifreeze (so,uh the engine won’t freeze…) and 50% H2O - distilled or tap at your option.

Cheers
Chris

 

There is a difference between just getting snow with the car in the garage and driving in it. I keep my garage temps above freezing because I store liquids there.

 

There's cheap insurance, and then there's not being smart just to save a few pennies.

There are several reasons to run a 50/50 mixture. Not only does it have a lower freezing point, but it has a higher boiling point. You raise the chance of overheating with a 70/30 water/coolant mixture.

Second, antifreeze also provides corrosion protection. With more water and less antifreeze, you get less corrosion protection inside the cooling system. Your water wetter claims to prevent corrosion, but if you skipped the water wetter and just used a 50/50 mixture, you'd likely be spending the same amount of money, and you'd get the added benefit of the higher boiling point.

What you're doing is a classic example of penny wise and pound foolish.

 

Desert guys run coolant as they'll boil on straight water, I was informed last week.

 

The boiling point difference between 30% and 50% antifreeze is negligible.

 

Mom and Dad's on the farm was the same thing. All sorts of theory's out there what is best to mix with. Some are for deionized, RO, Distilled and tap water. Other only this and never those, because usually they have no minerals so it tries to attack the various metals. I have used all including our current RO tap water without issues. I just use the universal yellow in everything I own. Keeps any worry of bad things happening. I saw what green coolant mixed with Dexcool does, modeling clay anyone?

 

As Joe noted, the boiling point difference is minimal (around 15* I think) compared to the freezing point, which is substantial (around 60*). This matters in some geographies much more than in others.

Also note that plain water can absorb and conduct heat better than water / glycol mixture. This is why I run 70/30 in my car since here in the desert I need all the cooling capability I can get and really have no need for freeze protection. Like Chris, I use 30% glycol for the anti-corrosion properties.

 

Gang,
Thanks for the echo on 70/30 mix approach. I don’t have a big thing about being right, but if 50/50 has higher boiling point, maybe I’ll do that next time.

I’m not fussed about a few bucks on coolant every 5 years either, I don’t drive these cars anything like daily, so I swap coolant more as a preventative maintenance / cleaning thing.

Observing the shape of Joe’s graph, is there a good reason to go the other way - 20% water / 80% coolant for added boil over protection?

I believe Fun71 is correct about water being a better absorbent/conductor of heat, so in theory you’ll never _get_ to that boiling point if things are working right, but it wouldn’t bother me to run more coolant and less water if that’s better for the lubricants, anti-corrosion additives and a higher boiling point. To be sure Northern California isn’t as hot as Phoenix, but we had 10-14 days this year of 100+ and at least 2 or 3 north of 110°, so I’m open to all theories and experiences with coolant.

Didn’t mean to ignite a kerfuffle over coolant, just trying to learn as I go after 40 years or so with these dinosaurs.

Happy Glycol to all
Chris

 

Chris, going to a higher coolant to water ratio actually decreases the heat carrying capacity and causes overheating. The manufacturers recommend a max of 70% but only in extremely cold environments where a 50/50 mix would freeze.

 

Plus, that chart appears to be at atmospheric pressure. Put the system under pressure and it will raise the boiling point. Doesn't lower the freezing point unless you get to like 60 psi by much, then only like 10 degrees F.

 

Agreed, but it raises the boiling point of all the mixture ratios similarly, so the delta T between them is essentially the same.

 

Is anyone here running Evans waterless coolant?

 

The difference between 20 and 30 is just as negligible. Why don't we run 20%, or even 10%? In fact, why run anti-freeze at all?





What is the difference in corrosion protection? If there is no harm in running 30% vs 50%, then why has every owner's manual since the beginning of time said to put in a 50-50 mixture? To sell coolant?

 

This is the chart that really matters. What do the various percentage mixtures boil at at 15 (or 16) psi, not 1 atmosphere.

At 16 psi, plain water boils at 252, a 1/3 mixture of anti-freeze boils at 260, and a 50% mixture gets is 267. 60% is even better, buying you a 13 degree increase over the 1/3 mixture.

 

Aren't you also the one who said in another thread that you run with a 7 psi radiator cap? A 30% coolant mixture at 7 psi boils at only 240. Seems risky to me, desert or not.

There's a trade-off here. Thermal conductivity increases with increasing percentage of water, but boiling point decreases.

 

Yep, that’s me with a 7psi cap and 70% water. Driving in 110 temps and not overheating.

You’re looking at the wrong end of the spectrum for why the manufacturers recommend a 50/50 mix. Why do you think it’s referred to as antifreeze and not anti boil? As I said above, 50/50 increases the boiling point around 15* but depresses the freezing point around 60*. Anti freeze.

 

Must confess I’d forgotten about my 16lb vented caps and puke tank effects until last night.

My engines won’t ever see 267°F, I’d surely shut ‘em down before 250 where ever I am, so I think I’m on the right track for my environment. If I hit 240°F, I’d assume there’s a failing component and just pull over to call the auto club.

Have heard of Evan’s Waterless Coolant - anyone here have experience good or bad to share?

I think there’s another version of waterless called Mishimoto’s or similar for those who hew toward the aluminum core radiators. I tend toward factory solutions over the years - like Xerex Green and distilled water, but I try to stay open to advances in technology which might well be possible with chemistry of coolant for internal combustion engines. I’m a believer in Water Wetter since I ran an A/B test a few decades back, temps drops 5-10°F as I recall.

Enjoying the exchange, carry on gents

Chris