Best way to flush cooling system

[FloridaEd]

It seems there's about 20 different ways to flush these things. I roamed around the site and finally decided to become a disciple of Gooch and went to Delo coolant after my 100k warranty was up.

I had the mechanic flush the system when he installed a new water pump (not really needed, but getting ready to go to Alaska again) and new hoses. I brought DISTILLED water for the mechanic to fill my system.

Then, I bought about 40 gallons of DISTILLED water from Wal-Mart and started the fill and drain sequence as many times as I could. I then filled my system with 1/2 full-strength Delo and half DISTILLED water. The Delo can says it's good for 375,000 miles as I recall, with another 375K with a booster additive. I bought two extra gallons of the 50/50 Delo mix for topping off.

When in the flushing sequence, remember to open the heater so it will circulate. IMO, you should only use distilled water ALL the time for the cooling system.

Anyway you look at it, it's a pain.

Florida ED

[catch&release]

Originally Posted by FloridaEd

Anyway you look at it, it's a pain.

Oh, it's not all that bad. What is bad is doing this flush and changeover to ELC, putting in a new 203 degree thermostat and billet housing after a thorough cleaning and drying, having it be fine for several months, and THEN having a small leak develop from the thermostat housing. It's a very small leak, but a leak nonetheless.

[Roadrunter]

I haven't had much luck with aftermarket thermostat housings and gaskets. They always seem to leak or need silicone. Best results (for me) are with new OEM housing and gasket. No leaks.

[444-4D]

Originally Posted by Roadrunter

The TSB looks to be more about checking the nitrite level (cavitation inhibitor) than top off dilution.

That was the point. The testing is for cavitation inhibitor yet there is no mention of cavitation inhibitor. The wording of the TSB indicates they are assuming if the nitrite level is low there has been dilution or contamination.

[Roadrunter]

The TSB doesn’t assume low nitrite levels are due to dilution or contamination. It doesn’t mention dilution or contamination any more than it mentions cavitation protection. If it was just about coolant degradation due to dilution and contamination, that could be checked using other more common methods, like refractometers and pH strips. Usually dilution and contamination are addressed by the coolant’s own recommended change interval. But this TSB isn’t saying to flush and re-fill, or check for dilution or contamination. It’s saying to check and add SCA (nitrite).

Nitrite levels are independent of dilution and contamination. You could have a perfectly clean and diluted coolant with low nitrite levels (SCA that depleted over a short time in a good operating cooling system). Or you could have a diluted and contaminated system with perfect nitrite levels (SCA added to crappy old watered down coolant).

Nitrite is specifically an additive (SCA) for cavitation protection. Testing the nitrite level specifically tells you who much SCA is in the coolant, not how diluted or contaminated it is. Aside from basic checks of coolant color and freeze point, this TSB is primarily about checking the SCA (nitrite). Ford oddly calls it checking the “anticorrosion strength”…Something that was promised not to be needed when using the “maintenance free” gold. We all know that VC-8 SCA and the 3-way test strips mentioned in this TSB are for maintaining the SCA, not dilution or contamination.

“3. Recommend checking coolant anticorrosion strength. Check the anticorrosion strength (nitrite level) of the coolant using the Rotunda 3-Way HD Antifreeze Test Strip Kit part number 328-00001 , 1-800-Rotunda (768-8632) option 2 or equivalent. Perform coolant anticorrosion strength at the frequencies recommended. (Figure 1)
NOTE: FAILURE TO FOLLOW THE SERVICE PROCEDURE AS INDICATED CAN RESULT IN INACCURATE TEST RESULTS.”

“Some customers, using their trucks under special operating conditions, indicate that operating with insufficient coolant strength (antifreeze or anticorrosion) can result in significant engine damage. Insufficient coolant strength can result when:

• Cooling system pressure and coolant is lost.
• The coolant level is topped off using the incorrect coolant.
• The coolant is mixed with hard water.
• Coolant is mixed at the incorrect concentration.
• Vehicles are operated under the special operating conditions as defined in the maintenance schedule (heavy commercial use that results in frequent or extensive idling, frequent low speed/rush hour traffic use; vehicles operated under special conditions such as: sustained high speed driving at maximum GVWR load, towing a trailer, using a slide in camper (F-Super Duty) or car top carrier (E-Series).”

“VC-8 Motorcraft® Diesel Cooling System Additive”

“Add 32 fluid ounces of Motorcraft® Diesel Cooling System Additive.”

If you do a search here you'll find several owners who tested their "maintenance free" gold and found it low on SCA. Nothing to do with dilution or contamination. Much to do with weak, depleted SCA.

[444-4D]

Originally Posted by Roadrunter

It doesn’t mention dilution or contamination any more than it mentions cavitation protection.

Yes it does. It is almost totally about dilution and contamination. You need to read it.

If it was just about coolant degradation due to dilution and contamination, that could be checked using other more common methods, like refractometers and pH strips. Usually dilution and contamination are addressed by the coolant’s own recommended change interval. But this TSB isn’t saying to flush and re-fill, or check for dilution or contamination. It’s saying to check and add SCA (nitrite)
Ford oddly calls it checking the “anticorrosion strength”…

Yes, that was my point in my previous post.

If you do a search here you'll find several owners who tested their "maintenance free" gold and found it low on SCA. Nothing to do with dilution or contamination. Much to do with weak, depleted SCA.

If you will do a search you will find that I may have been the first person to recommend adding additional SCA to G-05 coolant but that isn't the point of this TSB.

[Roadrunter]

So are you saying that if my gold coolant hasn’t been diluted or contaminated, then I don’t need to test and maintain it with SCA? Or does the TSB say that if I drive in rush hour traffic, tow, use a camper, etc. that I need to test and add SCA? Does testing the SCA (nitrite) really show if the coolant is diluted or contaminated, or does it just show how much SCA protection it has? Is SCA (nitrite) a cavitation preventer, or does it prevent dilution and contamination? Wouldn’t a diluted or contaminated gold coolant show correct levels of SCA if it had been used for a while and then diluted with water and SCA, or contaminated with another coolant that had SCA in it? Couldn’t non-diluted or non-contaminated gold coolant show low levels of SCA? Why do you recommend adding SCA to the gold? Isn't adding SCA to the gold diluting and contaminating it in the first place?

I guess I don’t think the TSB is that confusing. It indicates if you use the gold coolant in a diesel and do things like drive in rush hour traffic, tow, or haul a camper, then you need to test and add SCA. For whatever reason, it's an indicator that the “maintenance free” gold isn’t maintenance free. Not much different than the old green stuff…except Ford never had a special TSB to test it for SCA, and owners were adding all types of bad water and different coolants to it.

Wouldn't an ELC be better...provide longer protection, less inhibitor depletion, and stand up to more harsh use? I hope so. I made the switch so I didn't have to deal with maintaining the gold, SCA, or TSB's. I want my engine to last a long time by using the best stuff without the worries of the gold.

[444-4D]

Originally Posted by Roadrunter

So are you saying that if my gold coolant hasn’t been diluted or contaminated, then I don’t need to test and maintain it with SCA?

No I'm not saying that. Did you read my last post? "If you will do a search you will find that I may have been the first person to recommend adding additional SCA to G-05 coolant"

Or does the TSB say that if I drive in rush hour traffic, tow, use a camper, etc. that I need to test and add SCA?

If certain conditions exist, that is part of what it says. If you read some more it also says to replace it under some conditions.

I guess I don’t think the TSB is that confusing. It indicates if you use the gold coolant in a diesel and do things like drive in rush hour traffic, tow, or haul a camper, then you need to test and add SCA.

I don't think anyone is confused about the TSB beyond it being an odd testing method for corrosion protection.

For whatever reason, it's an indicator that the “maintenance free” gold isn’t maintenance free. Not much different than the old green stuff…except Ford never had a special TSB to test it for SCA, and owners were adding all types of bad water and different coolants to it.

I have always said it wasn't maintenance free. I don't consider any of them maintenance free.

Wouldn't an ELC be better...provide longer protection, less inhibitor depletion, and stand up to more harsh use?

Under some conditions it would. It wouldn't work any better for these conditions that you have chosen to ignore.

• Cooling system pressure and coolant is lost.
• The coolant level is topped off using the incorrect coolant.
• The coolant is mixed with hard water.
• Coolant is mixed at the incorrect concentration.

I made the switch so I didn't have to deal with maintaining the gold, SCA, or TSB's. I want my engine to last a long time by using the best stuff without the worries of the gold.

I use conventional coolant with DCA-4. I have no worries about the life of my engine or the 5 minutes and 5 bucks a year it takes me to test it. I'd probably test it once a year regardless of what was in there. If I drove 3,000 miles a week I might run something different. But if I drove 3,000 miles a week I'd test an ELC more than once a year, especially if I had an 03 up with an EGR cooler.

[Roadrunter]

Sorry about that. I assumed you knew I read your last post, since I asked why you recommended adding SCA to the gold.

Also sorry you thought I was trying to ignore those 4 conditions from the TSB, since I already posted and discussed them. I was hoping you understood that none of them would require testing SCA, and that ELC would be better in those harsh conditions because it dissipates heat a little better, tolerates hard water and other coolants better, and won’t deplete as fast in weaker concentrations.

I will have to agree to disagree with your idea that the TSB is almost totally about testing dilution and contamination. The heart of the TSB in steps 3, 4, 5, and 6 is clearly about checking SCA (nitrite) levels. Nitrite is the important inhibitor added to the gold to specifically protect diesels from cavitation, not dilution or contamination. The TSB addresses dilution and contamination by checking coolant color and freeze point in basic steps 1 and 2.

Testing SCA won’t show if your coolant is diluted or contaminated. It only shows how much SCA you have. You could have clean non-diluted gold coolant in your system and find low SCA, because SCA depletes as the engine is used. Or you could have old contaminated and diluted coolant with good SCA levels, because someone topped off with the wrong coolant with SCA in it.

Clearly the gold needs SCA maintenance because it can fall dangerously low just from towing, hauling a camper, driving in rush hour traffic, idling, and other basic ways we use our trucks. It doesn’t need to be diluted or contaminated to do that.

I think we can consider most other better heavy duty ELC “maintenance free”. They don’t require testing and adding SCA, and they last a lot longer. International doesn't have any TSB's out on maintaining their ELC coolant like that in the same engines used in harsher conditions.

I agree that all coolants should be checked for color, freeze point, and flushed at their life intervals. That’s basic. But this TSB turns what Ford said was “maintenance free” gold coolant into a coolant that requires maintenance testing and adding SCA, even for all the 2003 7.3L E’s and F’s listed in that TSB that don’t have EGR coolers.