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Radiator woes - verdict - 40% blocked

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Old 08-27-2013, 08:05 PM
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jwillman
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Default Radiator woes - verdict - 40% blocked

I have been fiddling with 2nd white line temps for some time. Many discussions have indicated that operating at the second white line is common and perhaps it is but my guess is that I am not the only one with a significant amount of blockage

I found an mom and pop industrial radiator shop locally and finally pulled the radiator to have them take a look. It is about 40% blocked and the shop can't rod it because it has the turbulators.

They are going to try a high pressure chemical clean but that will likely not get me to 100%.

I have been driving her as is so any improvement will be exactly that. Lots of other things for this car that I would rather spend $1000 on

More to come.
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Old 08-27-2013, 08:15 PM
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eijun
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I say have them clean it, then use Redline's WaterWetter during summer months which it slowly will turn the blocked stuff into gunk, then flush every other month until its clear?
Old 08-27-2013, 08:30 PM
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jwillman
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Thanks for the recommendation.

I added Water wetter the first coolant change when I got the car. If I can get some improvement from the radiator shops efforts I am will certainly try that before a different radiator.

Seems unless you go new you are likely to get another used radiator with the same issues.
Old 08-27-2013, 09:02 PM
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dr bob
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The turbulators are spiral ridges formed inside the tubes before they are flattened and finned. Purpose is to force the flow in the tube to constantly delaminate, avoiding a hot passage through the tube with minimum surface contact. The downside is that you can't rely on a straight tape to mechanically clear all the little voids and cavities formed originally in the tubes. Cleaning options include extended chemical cleaning/flushing, but that really requires at least a minimum flow path through every tube. A fully plugged tube won't have anything but the ends exposed to the chemical cleaner, so will stay plugged unfortunately.

Even with religious coolant replacement, I suspect that my original radiator has similar pluggage. Extended higher-speed driving in superheated central-valley conditions causes the gauge to work its way slowly up past where I like to see it. Slow down and the gauge reading drops. The symptoms describe reduced coolant flow. Might be a partially-opening thermostat, but the symptom has been slowly building over the last years.

I have a new Behr radiator just-in-case, but it's not painted and doesn't have stickers on it. I can try to have the original cleaned, or I can find some of the replica stickers and paint the top of the new radiator.

We are running out of real radiator repair/cleaning places these days. Most places just want to sell a new replacement rather than try to recover a sound but partially-blocked original radiator. Hey, mine is probably 25 years since manufacture; It should have plenty of life left with a little interior cleaning.
Old 08-27-2013, 10:54 PM
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You would be surprised at how many rads are already blocked to the level of 30% or 40%.
The great result is that mostly they continue to cool at acceptable levels.

Most of my early cars see the second white line which is very OK and way below anything of concern. The gauge is very inaccurate so use an IR gun to determine actual results at the top and bottom of the rad - you will be surprised at the result.
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Old 08-28-2013, 10:18 AM
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jwillman
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I recently used my IR gun and at operating temp I was 205 deg inlet and 195 deg outlet. Not much of a drop even with my dual electric fan upgrade but inline with my gauge readings as I understand it.

Hopefully I will get some capacity increase and also plan to drop to 25/75 coolant ratio to help out as well.
Old 08-28-2013, 05:21 PM
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I wonder if doing yearly flushes will prevent the block up or not for coolant users

(waterwetter/royalpurple users dont have to worry much if it was clear/new before)
Old 08-28-2013, 06:02 PM
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jwillman
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I don't know. I had drained and replaced 2 years ago and back flushed the radiator with a hose but did not drain the block. Likely the damage was done at that point.

The original coolant did not look bad but the coolant reservoir had a lining of black gunk that required allot of work to clean out so system had been ignored before me.

The coolant I drained was still clean, GO5 with Water Wetter, but did have some black granular seditiment in the bucket after draining the radiator and both block drains.
Old 08-28-2013, 06:10 PM
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dr bob
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Originally Posted by jwillman
...

The coolant I drained was still clean, GO5 with Water Wetter, but did have some black granular seditiment in the bucket after draining the radiator and both block drains.
I find that on almost every car when I change coolant. This last time (a week or two ago) I made it a point to use a clean white bucket. I used a funnel from the radiator drain so I wasn't washing crud from the nose cone into the bucket. Still got a few flecks of black something, and a few more from the block drains.
Old 08-28-2013, 06:13 PM
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dr bob
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Originally Posted by eijun
I wonder if doing yearly flushes will prevent the block up or not for coolant users

(waterwetter/royalpurple users dont have to worry much if it was clear/new before)
I'm not real sure what you are suggesting here. Waterwetter does nothing to reduce or remove mineral scale clogging the radiator.
Old 08-28-2013, 06:17 PM
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Great, now I got another thing to worry about - finding out if the radiator is blocked or not.

Well if they clear it to 80-90% then your good being waterwetter can take care of the rest as long as there is a mini-path. But you should ask them realistically how much can they clear.
Old 08-28-2013, 06:23 PM
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Originally Posted by dr bob
I'm not real sure what you are suggesting here. Waterwetter does nothing to reduce or remove mineral scale clogging the radiator.
Sorry didn't proof read and made it confusing. For flushes always use those formulated for coolant flushes (for others who are reading)

I was talking about waterwetter not clogging up the system when compared to coolants (that and it also turns the the mineral-zed coolants into sludge... sadly at a slow pace)
Old 08-28-2013, 08:19 PM
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Jim,
Your car has a later 85> radiator? You mentioned turbulators and the pic of the core of looks later.

Reason I bring this up is so people with earlier cars are aware their cores are 'non-tubulated' and 'rod-able'.
Old 08-28-2013, 08:37 PM
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Thanks Jim for that call out. I thought it might not be the original.
Old 08-29-2013, 01:29 PM
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Radiator shop called today and was able to flush and get about 90% flow. I hope to get it back in this weekend and what difference it makes.


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