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Cooling System Flush

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RJS

RJS

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Pure coincidence I performed my every-other-year cooling system flush yesterday and now we are having record highs in the Northeast. Hit 105 degrees at lunch today.

I used the Prestone Superflush product as follows:
1. Drained system, refilled with Superflush and distilled water. Ran at full temp for 10 mins.
2. Then drained, refilled with distilled water. Ran at full temp again for 10 mins.
3. Drained and refilled with the following:
12 oz Water Wetter
103 oz Prestone Anti Freeze
Topped off with distilled water.

Considering the system capacity is 2.1 gallons (269oz) and most of what was left in the block after the two drain and refills was distilled water, I calculate this gives me the following mixture:
5% Water Wetter
37% Anti Freeze/Coolant
57% Water

I am no scientist but, I calculated this gives the best compromise b/t protection (-10 degrees freezing and 265 degrees boil over) and cooling system efficiency (heat transfer).

Bob
PS: running the original rad which was boiled out about 10 years ago
 
Hi, I was just about to ask whether anyone had problems after using a radiator flush, like the Prestone product you use.

I used a radiator flush additive a year or so ago on an original rad and it promptly started to leak. I think it whatever gunk or rust that was removed was literally holding the core together. A rad shop deemed it unrepairable, re-core only.

I found a good used one online that was sold to me as cleaned and tested, it has been holding up fine over the last few hundred miles, even in this summer heat.

Although I am 99.9% sure the leaking problem was the original radiator's condition, I have been shy about doing another flush with the "new" radiator. I guess I was concerned how the flush could react with solder or something? Over-thinking it, I guess...

Nice to know you haven't had any problems with an original radiator and multiple flushes over the years... thanks for the post!!
 
Hey,

Just to add a comment to my post above, my car has run noticeably cooler this summer after my cooling system flush. More than the flush, I actually attribute this to two things:
1) the 63% Water/Water Wetter and 37% Coolant mix
2) when filling the rad, I jacked up the front of the car and burped all the air from the system via the radiator cap before sealing it up. When doing this, I could add a fair bit more fluid into the system

Most of my driving is on a Saturday or Sunday mornings on country roads where the car barely comes to a rest (continuous 30-60 mph). Before, my temp gauge would read smack in the middle. Now, I run a hair below the middle.

It almost makes me wonder if the thermostat is stuck in the open position. Is that even possible? It's a standard 185 degree T-stat from TRF 10 years ago.

Bob
 
It is possible for the thermostat to 'stick' open (in fact, that is how modern units are supposed to fail); but that would not cause your temp gauge to read in the middle.
 
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