Proper coolant 7.3 IDI

[ManBearPig]

I replaced the thermostat and radiator on my recently acquired '91 7.3 Turbo. I have flushed with distilled water several times and need to fill it back up with the proper coolant. The previous owner gave me a half empty bottle of Peak "fleet charge" that is pre-charged with SCA from when he changed the coolant 3 yrs ago, but I'm not sure if going back with something like this is the best idea. I recall from my Powerstroke days, that the earlier trucks that did not come with gold extended life coolant could switch to the ELC, but only if it met certain specifications. If possible, I'd like to go to the ELC in this truck. My understanding is that the ELC coolant does not need to be monitored for SCA levels so long as it is changed every 100k miles. Am I mistaken on this? I just want to go to something maintenance-free if possible, and figure this would be a good time to do so.

If the ELC does not work well in the IDI trucks, what am I looking for in a "regular" diesel coolant? Is something like the Fleet Charge any good? Should SCA still be checked with test strips when using this? I know enough to know that the correct coolant in these trucks is very important, but don’t know much beyond that. I've done several searches and have not turned up much in the way of specifics….just lots of "use the correct coolant" but can't find what that is. Thanks for the insight!

 

[79jasper]

Sounds like you didn't search here for which coolant.
Otherwise you wouldn't be questioning the use of Fleet charge.

Sent from my SAMSUNG-SM-G935A using Tapatalk

 

[ManBearPig]

Searching keywords like "coolant" and "fleet" or "charge" seemed to turn up page after page of irrelevant threads. The information may be here, but it is buried among other topics. i suppose I will keep digging.

 

[Clb]

Fwiw
In my querry for a brass usa made heater core' shaun listed the fact that fleetcharge( recomended here) used by me, is caustic to alum.
I have not asked brassworks anout this yet.
But inside of 2 yrs my core quit.
Look at my thread on ?"inside a 40k coolant system" thread for a picof the statt housing and hoses.
Again fwiw

 

[IDIoit]

as stated time and time again,
go to google and type in "oilburners- your criteria"
makes searching a hell of a lot easier.

 

[BDCarrillo]

as stated time and time again,
go to google and type in "oilburners- your criteria"
makes searching a hell of a lot easier.

Siteilburners.net coolant type

That'd also work.

 

[CDX825]

Ive had good luck with Final Charge ELC in multiple vehicles. Its one of the few that meets the cummins 14603 spec which means its safe for older seals and gaskets.

ELC is the way to go though. No need to worry about SCAs ever again. No silicate drop out or SCA drop out. Water pumps last longer with it. Last time I check most were rated for 5 years of service or 600,000 miles.

 

[Shawn MacAnanny]

Fwiw
In my querry for a brass usa made heater core' shaun listed the fact that fleetcharge( recomended here) used by me, is caustic to alum.
I have not asked brassworks anout this yet.
But inside of 2 yrs my core quit.
Look at my thread on ?"inside a 40k coolant system" thread for a picof the statt housing and hoses.
Again fwiw

Aluminum begins corrosion at a pH above 8.5, copper above 9.5. Sodium molybdate slows down this process, sodium nitrite possibly can. Fleet charge has a pH of 10.0 when i tested it, about 2200ppm of sodium nitrite @50% DI mix, no molybdate and im going to assume no tolyltriazole if they cut out the sodium molybdate to save money. The Primatech Fleet coolant from Fleet Pride has a pH of 11.0. The regular green non phosphate has a pH of around 9.5 and still the 2200ppm of sodium nitrite, no molybdate. I choose to use the fleet charge knowing it's a higher pH because it protects the cylinder sleeves from oxygen pitting.

The higher pH allows formation oof magnetite. It will kill aluminum and copper eventually, but a radiator or heater core are much cheaper than cylinder sleeves. I also add my own almost 300ppm of sodium molybdate and 60ppm of tolyltriazole. The number one killer of aluminum is copper ions. They will find a place, plate onto the aluminum and bore right through it. The tolytriazole bonds with copper instantly and forms a layer around the copper and prevents it from depositing on the aluminum. Your block heater element is copper, and your oil cooler bundle tubes are copper.

My best suggestinon would be to use the regular green coolant and add the ford motorcraft additive which contains both sodium nitrite and sodium molybdate, i am unsure of azole but it may be in there, i never tested for it (its about a 30 minute test requiring UV digestion) The fleet charge from tractor supply is the best bet to protect the cylinder walls, you could even add the motorcraft additive but i chose to add molybdate and azole only. 2200ppm of sodium nitrite is really the maximum you should run when there is aluminum or solder joints. I am not sure where anyone can just purchase the correct additives but the sodium molybdate in the motorcraft additive is what will protect your aluminum.

Here is inside of my 200k engine, had green coolant when i got it, radiator cap that didnt hold presssure, previous owner knew nothing of SCAs, engine didnt seem too well cared for, but the nitrite did what i consider an excellent job fo protecting the iron surface for 26 years

 

[Clb]

Great info' sticky /tech worthy