Rad flush

[triton28]

So while making up some test leads for relay testing I decided to start my radiator flush and I let it sit for a 2 hour soak using the pictured CLR solution. The rad had previously been pressure tested to 20 lbs and I will retest it to be sure that after all the soak timelines, 2 hour; 4 hour; 8 hour and 24 hour, I haven't eaten a pin hole in the core.
The photos tell the story; radiator, CLR and the clear glass jug to show the residue removed, if any.
After 2 hours I drained out the fluid and found nothing! So upon inspecting the interior of the rad I discovered that in my haste to conduct this experiment I had omitted one important step: use a cruddy radiator. I had used one of my good ones so I will start over after I make the trek to my hidden stash of used radiators and find a cruddy tank/core one.
I had to leave this experiment undone until I finished my income tax return, due today, but I will then continue and post the results.
Dave

[ekap1200]

Hello from New Jersey, Dave I had to giggle and think of the saying "don't fix it if it ain't broke" and now a new saying to remember is "don't clean it if it ain't dirty"

I see a hose ( 8101 ) on that rad. What brand hose is that ? and are you thinking of fitting it to the upper rad-connection.
I keep looking for good alternatives and had found a perfect replacement for the two upper's on the head. Loren and Tony can verify this as we were all together when I sprung a leak . Happened a mile from our motel and next door was an auto-zone . I have never had to flush / clean any radiator, I use the rad shop over in Berlin,NJ . Been dealing with them so long on heavy equipt. that he does the tiny rad's for me at a very low rate and good turnaround time... I have replaced the coolant in mine a few times in its life and had never any issues.
Gene K.

[triton28]

Hello Gene;
My luck to pick a clean one and not notice! But,,,, I will not be deterred. (Provided I can find a crusty one as I have had some so long I don't remember if they are crusty or not, I will have to check them first). The nearest rad shop to me is about an hours drive away so being frugal, (cheap), and on a fixed income I try to find alternatives closer to home.
That 8101 hose is the Canadian NAPA number for the Dayco B71260 mentioned in the Dollar4Dollar section, stated as replacing hoses 39062-1151 and 1152. I haven't used up my OEMs yet so it is just sort of hanging around.
One hose which I ran across that looks as though it may work for the discontinued bypass hose is the Dayco 80412. I have not purchased one so that is only a guess as the o/all length may be a bit short. Hmmmmm, I will measure one of my OEM bypass hoses today and see if the Dayco length will possibly work. Off to the secret parts shed!
Dave

[Nails]

I wish I could go back in time and donate my radiator. My XII, which only a fool would've bought, probably had all original fluids. (Maybe they did replace it once. The overflow hose got pinched closed somewhere along the way.)

I replaced those thermo housing o-rings, and things looked pretty skanky inside. I did a Prestone flush and marveled at the semi-liquid substance I got back. The second flush also was absolutely shocking. The third flush (just water) was still semi-opaque. The fourth flush (radiator fluid) finally came back passably green. It's a thousand wonders it didn't spring a leak.

I hope you get a good demo here.

[triton28]

Damn Nails;
I just finished hand cleaning all of my spare t'stat housings too. They would have been easier to do this experiment on, oh well.
I have a second rad soaking now and will see how this one does. I checked all my spares and they were all really clean but I will run this one anyway.
I measured the OEM bypass hose and the Dayco 80412 has a stated length of 12" but the OEM measures a straight 15-3/4" when new so the 80412 is probably a no go.
However the NAPA NBH 10876 does appear to be extra long and can be cut to length. It is 16mm ID, 5/8', so it may be a loose fit. I will measure a new bypass hose when I go to drain the 2 hour flush.

[triton28]

So this radiator did exhibit some discoloration to the CLR after the 4 hour flush, actually just filling the rad with the CLR and leaving it stand for 4 hours. As well there was a small amount of debris/solids in the glass jar I poured the CLR into.
I will post photos of this and the 8 hour exposure to CLR tomorrow but for now I wanted to report on the NAPA NBH 10876 possible bypass hose replacement.
The bypass hose stub of the radiator has an OD of 13.75mm--17/32".
The rolled lip/rim of the stub has an OD of 15mm--19/32".
The ID of the OEM bypass hose is 12.55mm--1/2".
The ID of the NAPA NBH 10876 is 16mm--5/8" according to the NAPA page.
Since the NAPA hose is only 1/32" larger than the rolled lip of the stub I suspect that a few wraps of teflon tape followed by some non petroleum based silicone brake grease to permit ease of sliding on of the hose and the NAPA hose may just work.
The published length of 26+" for the NAPA hose would leave plenty of length to match the OEM as one can see the unused hose measures only 15-3/4" in straight length.
Dave

[triton28]

I gave up on the 1st radiator as it was too clean to begin with. So this time I used a 2nd radiator which was also clean but did exhibit some crustiness of the core tops in side the tank; not bad corrosion but evident. After 4 hours I completed filtering the 4 hour CLR from the radiator and reintroduced it back into the radiator for the 8 hour test.
After the 4 hour test there was a small amount of dirt present in the filter I used and a slight discoloration of the CLR.
At the end of 8 hours I again removed the CLR and ran it through a filter. This time there was a noticeable amount of soft, powdery (when dried) residue from the radiator. As well the liquid had a definite darker, dirtier colour to it.
The interior of the radiator tank was definitely brighter looking than before the 8 hour test and the core tops were now shiny and perfectly clean. I conducted a pressure test to be sure I had not corroded any of the radiator and the 20 lbs I introduced kept constant for 5 minutes, so at least I know the CLR doesn't corrode the tank or core.
So to sum up the first 2 tests, bearing in mind that I couldn't find a radiator similar in crustiness to the one Nails described, I would have to say it does work as witnessed by the 8 hour results.
I will be conducting a 16 hour test with a different 3rd radiator and I will be using fresh CLR. I suspect it will show increased disclouration and there will be an increase in debris/crud in the filter. We'll see.

[Nails]

I couldn't find a radiator similar in crustiness to the one Nails described

Not even close. I'm pretty sure I had factory rad fluid, or maybe changed about once, a very long time ago. Dunno -- but you'd still be filtering. "Skanky" doesn't begin to do it justice.

You're picking radiators that have been maintained.

Now, if you want to see something really scary, you should've been here when I drained the shocks. It reminded me of pus more than anything else.

On any new-to-you XII, fergawdsakes change the fluids. All of them.

[triton28]

Yes Nails when I was buying up the world's supply of used radiators I would look very closely at the photos showing the stubs and sometimes the interior of the tank. If it looked OK it was what I was looking for and I would have to agree that all of my spares appear to be from maintained cooling systems. I have also used the Prestone flush when I had an operating system I wanted to flush and can also attest to the effectiveness of that product. It does work well.
I am going to start the 16 hour test tomorrow night with a 3rd rad just to see the results of using the CLR. I suppose I could have used the bottle of Prestone I have but I am saving it to use on my '90 which is due for a system flush this year. I used the CLR because the company hypes the removal of hard water deposits so much I just had to try it!
If one compares the colour of the new CLR against the used liquid there is quite a lot of discolouration probably due to mineral deposits, either in suspension or solution now, from not using soft water in the system.
Changing ALL the fluids is a must whenever someone purchases a new to them used machine. It is amazing some of the gooey liquids one discovers while establishing a new owner baseline for future fluid changes.
Dave

[Nails]

And so?

Ya-know Dave, I'm gonna go out on a limb here and speculate what your problem is: I don't think you're even capable of buying junk. All you can do is buy good parts. So of course this little exercise is gonna fail.

[triton28]

I must confess to being remiss with the 16 hour test but I will get to it today I assure you. Yes Nails I have been very finicky with the used parts I buy and it is difficult to find a bad one,,,, although,,,,,I did find this:
I did try this using the CLR and it was a total failure other than dulling the colour to flat brown. In fairness though the rust did sort of slide off with a light brass wire brushing and this t'stat is now safely ensconced, shining like new, with all the other t'stats in the dark dungeon like used parts vault.
Regards,
Dave

[triton28]

This time I used a rad that I had taken to a professional rad outlet a few years ago to have the rotted stubs replaced. They advised me that their work would consist of a flush and rebuild of the stubs. I returned several days later and sure enough the stubs were rebuilt complete with sealing lip. So I paid the man and went home to secret the rad away in the large cavernous camouflaged used rad vault for future requirements. I had done an inspection of the tank areas and all looked clean, but little did I know what was lurking in the core!
I had a hunch, as unfortunately I have come to realize in dealings with third party service sellers, that perhaps this radiator would be the one to approach the horrors witnessed by Nails during his coolant system flush.
Not quite I suspect, but after a 17 hour, ( I slept in ), exposure to the CLR I drained it using my mad scientist plastic funnel and coffee filter device. The results were very interesting to say the least. It took 2 filters to collect the residue and 3 hours to run through the filters. The results in the photo are the collected sum of the 2 filters.
This time I also decided to filter the water flush/agitate I used to initially purge the CLR. An additional quantity of calcified minerals was collected, photo 3, and then added to the first amount.
Next I weighed all of the residue and it totaled 4.35 grams. Now this may not seem like a great weight but imagine it spread out clinging to the narrow channels the water must flow through which makes up the core.
Next I pressure tested the radiator and it again maintained 20 lbs for 5 minutes so I didn't eat the core up with the CLR it seems.
So I would have to classify the use of CLR on a non-installed radiator as a success BUT, it appears as though it will take at least 16 hours to de-calcify the minerals. Would I do it again? If I was to buy another used radiator that was unknown condition on the interior I most certainly would as it is a set it on the workbench and forget it way to de-calcify a radiator, so it unscientifically seems. I would not bother to do this with an installed radiator as the Prestone Flush is probably the way to go for functioning coolant systems. But I wonder??????? Perhaps if I get really insane I will flush a functioning cooling system and then go to all the trouble of removing the radiator to test the true quality of the Prestone to remove minerals. Hmmmm,,,,, I don't think so!
So there it is, the workbench rad flush to end all rad flushes. Note I don't recommend this for anyone other than myself as I had all these used radiators and this question about the claims of the manufacturer to remove hard water deposits, so if it ate up a core I was only out a used rad and not off the road.
For what it's worth,
regards,
Dave

[Nails]

I suspect that some of that golden crud in your earlier post might be the result of incompatible metals in the caustic flush.

I recently tried to clean up some coins I found in the floor area of a nasty old car I bought for parts. (Yeah, I'm cheap. I might even stop for single shoes found on the road.) I separated the silver coins for treatment, trying three different metal cleaners I found under the kitchen sink (a CERCLA site in the making). All three actually increased the dark tarnish. But then I noticed some pennies in the mix -- the coins were so tarnished I couldn't tell when I first sorted them. Taking them out, the silver coins came clean enough that a store might actually accept them.

My point is that I'd have reservations about using CLR in a whole-system flush, out of concerns that it might cause metal ions to dissolve from one metal and deposit on another. I assume Prestone has taken that into account, such as when they state that it's suitable for aluminum blocks. CLR might've been developed just for stainless steel, chrome, and ceramics.

The "gold" in your crud might have come from something valuable in there somewhere, as opposed to, well, just crud. (You'd think that with an expensive college degree in chemistry, I might be able to do more than this shitty speculation. But that was a long time ago, I never actually used much of that education, and now I'm too fat and lazy to get any further into it.)