1963 Riv w/401 - coolant capacity and mix?

[JanZverina]

With the coolant capacity in the factory Chassis Service Manual listed in Figure 1.1 at 18.5 quarts (4.65 gallons), what do folks recommend as far as the coolant to water ratio? O'Reilly's sells the 50/50 (coolant/water) gallons but what are some other recommendations?    

[RivNut]

50/50 is fine ne but don’t buy the mix. Water is basically free; why pay for it?

[JanZverina]

I agree, Ed. So about two gals or so of coolant and the rest of the fill with water? Do you recommend any other 'treatment' or additive?

 

[BulldogDriver]

Buy 2 gallons of full strength “green” antifreeze and 2 gallons of distilled water. Pour 1 gallon of antifreeze and water into radiator. Then pour 1/2 gallon antifreeze into empty jug and add 1/2 gallon water. Pour the other 1/2 gallon water into the other antifreeze jug. Shake vigorously and top off radiator.
 

Job done.

 

Napa charges about the same for 50/50 as for full strength in my area.

 

Ray

Edited August 8, 2023 by BulldogDriver (see edit history)

[avgwarhawk]

I recommend nothing but the green antifreeze mixed 50/50.  Replace every two years. 

[JanZverina]

Thanks everyone, much appreciated!

[MrFreeze]

3 hours ago, RivNut said:

50/50 is fine ne but don’t buy the mix. Water is basically free; why pay for it?

Distilled water is about $2 per gallon at my local grocery stores.  Less than coolant, for sure, but it makes the convenience of purchasing pre-mixed just a BIT more attractive.

 

MrFreeze

[NTX5467]

IF you are going to pull out the block drain plugs and drain it fully, then take the 2 gallons of green coolant and 2 gallons of distilled water to make a 4 gallon 50-50 mix to refill the block (via the thermostat housing) and then the radiator (with all of the hoses connected), plus a dry heater core, with 50-50 mix, that can be a good bit of labor involved.

 

What I used to do was to flush the block with a garden hose (engine at hot idle and the radiator drain open), then let the radiator drain.  When empty, close the drain spout, and refill the radiator with pure 100% green coolant.  On the car we had, filling the a/c rated radiator usually would take 9qts of coolant, resulting in a -34 degrees F protection level.  Then run the engine to purge any air out and re-check the level.  Cycle repeat every two years.  Worked just fine for us.

 

The whole deal of buying 50-50 mix coolant, already mixed, is a more modern invention.  Use it for top-offs and such, rather than complete "drain and fill" operations, to me.  If using DEXCOOL, it is allegedly supposed to be put in the engine in a 50-50 mix orientation, according to GM.

 

The need to change the non-DEXCOOL coolant every so often is to keep the coolant additives from degrading the solder holding the radiator and heater core together.  Additives in the normal coolant keep that from happening, but when the additive package degrades, the two enemies (ethylene glycol and solder) start to fight each other . . . according to a BASF Coolant brochure I found in the 1980s.  If course, if your radiator is welded aluminum or is a composite radiator, then the only solder would be in the heater core.

 

Enjoy!

NTX5467

[XframeFX]

45 minutes ago, NTX5467 said:

the radiator drain open

Ha, I just purchased and installed a flush 1/4" NPT socket plug to replace the radiator drain today. Otherwise I would have to remove the passenger side lower radiator saddle.

33 years is too far back to recall where I acquired the radiator. Obviously incorrect to my '63 Riviera. A sad looking radiator but I'm running it! Tomorrow, will figure out how to mount the bottom of the fan shroud ? ? ?

Edited August 9, 2023 by XframeFX (see edit history)

[RivNut]

On cars with a/c, there are two 90 degree brackets the are bolted to the backside of the radiator core support. They have a rubber sleeve that fits over the.  The two holes in the bottom of your shroud. The shroud is held in place with the one bolt that attaches to the radiator support bracket.  

[60FlatTop]

8 hours ago, NTX5467 said:

but when the additive package degrades, the two enemies (ethylene glycol and solder) start to fight each other . . . according to a BASF Coolant brochure I found in the 1980s. 

In the 1990s we found that the fight could produce 1.5 volts by making the system its own little battery. That could cause some of the 0-5V or 1000 Ohm sensors to give false readings.

 

I would like to think that I change my antifreeze every 3-4 years but that is more one of those "do as I say, not as I do" things.

[JanZverina]

Anyone know the torque specs for the thermostat housing? ('63, 401). The service manual lists one for the water manifold but not the therm housing. Previous experience tells me to be real gentle and go side to side a lot...

Thanks!

-Jan

[NTX5467]

10 hours ago, 60FlatTop said:

In the 1990s we found that the fight could produce 1.5 volts by making the system its own little battery. That could cause some of the 0-5V or 1000 Ohm sensors to give false readings.

 

I would like to think that I change my antifreeze every 3-4 years but that is more one of those "do as I say, not as I do" things.

One realization of "the coolant as 'ground'" was when an associate (who taught at a local automotive trade school) commented that "good" coolant was necessary for the many coolant-touching sensors to give the computer a good and accurate reading.  This was in the later 1980s. 

 

Might this have been a side-issue for the extended-life coolants, such as GM DEXCOOL, which have a specified lifespan of 5 yrs/100K miles?

 

NTX5467

[Bloo]

If you have 1.5v in the radiator you are going to have a really bad time. This isn't new. It's called radiator electrolysis, and will destroy your radiator. Dyke's Encyclopedia covers it.

 

I don't believe in the extended change intervals. I have a strong suspicion that was driven more by service interval requirements for US EPA emission laws than any special capabilities of modern antifreeze. I don't know for sure, but If i were a betting man....

 

I have been using modern coolants since the mid 1980s. I change it out every 2 or 3 years. People want to blame their radiator rot and aluminum rot on DexCool, but the real problem is people who are uninformed, misinformed by unrealistic claims about coolant life, or too cheap to change their coolant. That was as true in the 80s as it is today. People who did not change their coolant had radiator rot and seepage, corrosion under every hose connection eating the fittings up, and coolant seeping out through the little strings that reinforce the hoses. You could SMELL those cars rolling into the shop. You didn't even need to open the hood.

 

I started out in the mid 80s with some modern formulation a radiator salesman recommended. It was green, and ever skeptical, I didn't believe it was any different than any other coolant. I didn't believe it that is until I had a small leak under the hood. Instead of leaving a dried out green slimy mess that is very difficult to even wash off, it left a little trail of beige powder. On the strength of that alone I was sold, and used it in everything from that point on... until about 1996, when the supplier told me it was discontinued. They said. "GM is making this now and putting it in everything, we weren't making that much of it anyway and there is no reason for us to continue. Go to a GM dealer and ask for DexCool, it's pink, but otherwise about the same formula". Sure enough, if you get a tiny leak, DexCool leaves a little brown powder behind instead of a slimy mess just like that older modern-but-green coolant did.

 

People have been telling me the sky is falling as long as they could see the coolant I use is pink (today it looks more orange). I still have not had any ill effects. All my cars have it except two (and those two have other modern formulas). As an example I have a 91 Geo Metro. It has had DexCool since I bought it in 96 (changed regularly). In 2012 I had the engine, transmission, and dashboard out of it for unrelated reasons, and I figured I'd pull the heater core out and replace it while it was easy. It is brass/copper and it looked brand new, so I put the old one back in. The original radiator is an odd duck with crimped plastic tanks, but the core is copper/brass (not aluminum). It is also doing fine. Another example is my truck (1966), which had a really rotten looking original radiator in it when I got it in the 80s. It's had DexCool in it for decades now (changed regularly), and that radiator is still there, still looking scary as hell, and still doesn't leak. I've never even seen the heater core in it. Literally everything about the heater is broken, so I suppose I will soon. No coolant is running out of the heater box. I keep waiting for all the massive destruction this "DexCool" stuff is supposed to cause, but I'm starting to think all these radiators and heater cores are going to outlive me.

 

[NTX5467]

When Dexcool came out, the GM rep told me that in the first 3000 miles of use (as it was recommended only for new vehicles which came with it from the factory), a chemical in it would coat the water jackets and such with a coating to kill corrosion and keep it from starting.  It was not recommended for older vehicles which had already had green coolant in them.  Again, his "recommendations".  Yet I also suspected that in an older vehicle with a freshly-vatted and rebuilt engine, adding a new radiator and heater core into the mix, would be the same as a new vehicle, in cooling system aspects.

 

By the time Dexcool was introduced, ALL used coolant was supposed to be collected and recycled.  With the long service life of Dexcool, GM mentioned the HUGE amount of used coolant that would not need to be put into the recycling system . . . as an ecological benefit.  Dexcool was supposed to be silicate-free, which was supposed to mean longer water pump seal life, but V-8 Silverados with Dexcool still needed new water pumps at about 80K miles back then, anyway.

 

It DID seem that as long as the coolant was kept at its normal level in the coolant recovery tank, no problems.  IF the coolant was seeping out and that low level got to the radiator tank, THEN "pink sand" could appear in the radiator filler neck.  Which vehicles this happend to, by observation, was not the complete spectrum of GM vehicles.  As I understand it, with the many complaints on the Internet and eisewhere, GM started to inspect the lease vehicle they got back in (personal and otherwise) and determine what the issues were.  In a few years, it seemed that ALL such issues tended to vanish, never to be heard of again.

 

There are multiple chemical formulas for "long-life coolants".  Dexcool is ONE, but Ford and Chrysler have their own specific coolants, too, for example.  Different, but related, chemistries which allegedly do NOT mix.  Yet Prestone and others now have universal coolants in addition to Dexcool.  Valvoline hits Ford and Chrysler, as I recall.

 

By observation, normal coolant can be added to Dexcool, in an emergency situation, the GM rep noted, but when Dexcool becomes contaminated, its benefits are diminished.  He noted that for the long-term benefits of Dexcool to remain, the contaminated coolant needs to be drained and replaced with fresh Dexcool as soon as possible.

 

When Dexcool becomes contaminated with "green", the resultant mixture looks like liquid mud, by observation.  Normally saw that in the first years of Descool, as most customers did not know what "Dexcool" was back then, they just knew "antifreeze", so they bought the cheapest version they could . . . just like they had been for years.  What could be different?

 

The BASF coolant pamphlet I picked up noted that ethylene glycol eats lead solder, so additives in the coolant prevent/diminish this activity.  Reason to change coolant rather than just corrosion protection.  Of course, with the newer composite radiators and heater cores, no lead solder in the cooling systems since about 1992 or so, if not more like 1982 (when we saw the first composite radiators on Camaros and such).  Somewhere back then, I discovered that many over-the-road trucks had "crimped and gasketed" radiator cores, rather than soldered-in ones.

 

Enjoy!

NTX5467

Edited August 10, 2023 by NTX5467 (see edit history)

[60FlatTop]

When I am busy with a lot of garage stuff this can is usually ready for jobs from topping off to refilling. Two gallons of concentrate and two gallons of water will keep me going for a while.

 

I just took the picture after supper and it was dry. I have a couple of O2 sensors coming in tomorrow so I will pick up a couple of gallons and refill. I want to change the coolant in a couple of the cars.

 

Always being the cynic, whenever I see a manufacturer touting extended life of any product I see it as a ploy to get a gold star from the EPA first and my benefit second. I know when I change the coolant, change the oil, flush the brake fluid, flush the gear juices, and various arcane rituals I also poke around and look at lots of things many never see. I like doing that.

[NTX5467]

What somebody needs to perfect is a recliner that can transform into a low-profile motorized creeper so "getting up and down" is easier to do.  I find it to be stress relief when laying under a car secured on jack stands.  Looking up at it as some might gaze at the night sky and twinkling stars.  Looking at everything in the process.  But, alas, after that long-lingering drop of motor oil finally drops into the drain pan, time for action . . .    Otherwise, one of those oil extraction electric pumps can work well.

 

NTX5467