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Coolant change question

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sparkydave

sparkydave

Jedi Knight
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Hey all, it's approaching the time to change the coolant in my Midget, and I may have to change the coolant in my girlfriend's Subaru too. I've noticed that pure antifreeze seems to have disappeared, and now it's all the pre-mixed stuff. That's great, but the method I've heard for replacing coolant involves flushing with lots of water, and inevitably there will be water left in the system somewhere. If you had pure (like I used to be able to get just a short time ago), then you put in enough pure to make up half the cooling system capacity, and then you top up with pure water. So how do do this if all they have on the shelves is pre-mixed? Seems like you would end up with less than 50% antifreeze if you tried to flush at the same time.
 
I rather think if you purge, flush, drain and refill with the pre-mix you'll be awfully close to where it should be. A specific gravity tester would be a cheap way to check, too.
 
If you do mix your own,be sure to use Distilled water in
the mix.
A friend of mind told me this,as there are less minerals
in Distilled water.

- Doug
 
I don't want to pay for the water in the pre-mixed, so I buy pure and do my own mixing, 60% coolant 40% water. Who says that pure coolant is no longer available? you've been shopping at the wrong store. Try Autozone, Walmart, etc. They have both. Have you noticed they cost the same? and yet you're paying for WATER! AGUA!

If you still end up with water in the block after draining, you haven't drained the block. There's always a block drain plug somewhere, you'll need to find it.

I always flush with Prestone Super Flush twice; Add one Super flush, fill system with water, drive around the neighborhood with Heater in full hot, until car has gone through 2 or 3 warm-up cycles. then come back and drain radiator and block. Repeat with the second Super Flush, this second time car will be warmed up so everything goes faster; The third and last time you need to flush the flushing cleaner, fill again with plain water only, the engine does not care about distilled water, it's only a temporary fill. then drain again and fill with whatever mix you prefer. More coolant in the mix is better. 60/40 is recomended. If you do it correctly, you can go 24-30 months with the same coolant. Every 12 months is overkill. Remember to keep the Heater ON in FULL HEAT all the time when doing this.
 
Thanks, but I have been to Autozone and Wal-Mart. I won't say I'm very fond of my local Autozone though, they frequently seem to be out of things. The remaining water in the Midget is usually lodged in the heater core, since there is a drain plug on the block. I'd rather not buy the pre-mixed for the same reason you stated; I'm getting half of what I get in the pure stuff for the same price.
 
I would call Prestone and ask them why you can't get a Gallon of Pure Antifreeze in your area. Or ask them to tell you who has it. I agree that Autozone runs out of items often, just like they run out of employees, but again, any auto part store should have it. I use Prestone because it's a proven product. I would suggest that you remove the Thermostat whenever you flush the system, when you're done flushing, replace it with a new one and new gasket. For $5.00 or so, it's worth the trouble, thermostats wear out in 2 years or less depending on how hot your engine runs. In my cars, I replace it every time they get flushed, and for the purposes of Flushing the system, the thermostat gets in the way of a thorough cleaning job.

If there's still some water in the Heater core, there should be a hose you can disconnect to drain it, but if not, no more than a Quart of water would remain in there anyway, so it's not an issue.
 
Dave,
I was in the WalMart in Streetsboro, very close to you, last Saturday and purchased two gallons of "pure" Prestone. They also had the 50/50 mix and it was the same price as the "pure"..why pay for water?
 
Why pay for water? Well, yes, for me in San Francisco it would be absurd, but in an area with very hard water I think there may be something to be said for avoiding putting all that dissolved calcium into the engine and furring it up like a kettle.

Ken G, 1925 Rover 16/50 (San Francisco)
 
Advance Auto, NAPA - they also have pure...yep, 60/40 mix...
 
... with a bottle of redline water wetter. I use it in all my cars.
 
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