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Discussion Starter #61
It's a lot easier in metric! Density of water is 1gm/cc or 1000g/1000cc (liter). Shop manual says to use 10% citric acid. So you add 100gm per 1000gm of water (1 liter). (100gm=3.527 oz)

Capacity of cooling system is 15L? So, you would need 1500gm (1.5 Kg) of citric acid powder in 15 liters of water. (1500gm is about 53 oz.) So your 40oz would be a bit weak, but probably OK!

Best to stay away from fluid oz - those 40 ozs only apply to beverages ;)
I got a total of 3.3 pounds so I'm not far off.
 

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Discussion Starter #62
I bought 3 x 500g bottles from the dealership. What I remember about it was how easily it dissolved in distilled water. I was also surprised how much grit came out given the clear flush after the detergent process.
Do I have to use distilled water? Will minerals in tap water interfere with the process?
 

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Sidebar: I'm currently rebuilding my '83 380 and have the block bolted to an engine stand. I rolled it outside for de-greasing and cleaning and then used compressed air to dry it off. When I aimed the air nozzle into one of water jackets I was immediately pelted by thousands of grains of something that looked like white sand. I assume it was calcium deposits. It took several minutes of constant air into the water jackets before the bombardment of white particles dropped to almost zero.
Conclusion... should you use distilled water? Yes. Cleaning out with tap water is fine, but once it's all cleaned out use only distilled water in the final mix.
 

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It should be fine to use regular tap water to dissolve the citric acid. MB don't say otherwise. What they do say, is to flush the engine 3 times with tap water (running engine for 5 min in-between) after doing the citric acid treatment.

Once you have this done, you could buy pre-mixed Zerex G05 coolant or more economically, dilute your own with distilled water. But if you do that make sure the distilled water is pure!. Depending on where you are you may need a different concentration, but 50% gives protection to -37C, I believe. Concentrations should never be over 55% antifreeze.

This link gives water spec. https://www.dropbox.com/s/zy0ght0naqahgv2/Antifreeze Spec_310_1.pdf?dl=1. They say you can use tap water, but to use distilled/deionized water if water quality is poor or unknown. Pre-mix overcomes need to know :) I use it for top up, but do my own dilution when refilling.

This might also be of interest:
 

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Discussion Starter #66
So this is where I'm at. I did the tide and citric acid flushes ( if you do a citric acid flush, wear gloves and eye protection, that stuff stings!) and then filled system with Zerex G05 coolant. With the citric acid flush, the water came out brown but there wasn't much in the way of solids that came out. Just about 2 teaspoons of what looked like grains of sand. Went out driving for about an hour, in stop and go traffic as well as on the freeway. Temp got up to around 100 in stop and go. Checked it with the infrared thermometer and it was actually 90 at the thermostat. On the freeway, the temp was reading at about 90. Got off and checked it and it was 80. At this point I think I'm good but I'll drive it in traffic again tomorrow just to be sure.
 

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Mirv, that sounds absolutely normal! My temp guages seriously moves between 80 and 100 depending on outside weather conditions and AC usage.

It sounds like your gauge may also be slightly inaccurate. If you haven't yet, add an extra ground to your cluster . That might give you a more accurate reading.

So long as the guage doesn't go above 100 with hovering between 80-100 you should be ok.
Congrats on the new monster car :)
 
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