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Preps & treatments

New parts ship dirty, and coolant is a poor cleaner. These get the loop clean so the coolant only has to cool. Two kits if you want the decision made for you, five bottles if you want to build the sequence yourself.

Start here

Which one do I need?

Brand-new parts, nothing has ever run through the loopComplete Prep Kit — New SystemRad Clean → SysPrep → PrimoPrep
Rebuilding a loop that has already run coolantComplete Prep Kit — Existing SystemRad Clean → System Reboot → PrimoPrep
New radiator, you already have plastic fill-port fittingsRad Clean — StandardHalf a bottle in 32 oz of distilled, per radiator · plastic caps only
New radiator, you don't have plastic fill-port fittings yetRad Clean — Full KitConcentrate + plastic fittings + funnel, all in one
Switching from an opaque fluid to a clear oneSystem RebootLifts dye staining as well as residue
Annual service on a healthy loopRad Clean + SysPrepRadiators, then a full-loop pre-treat
Mixed-metal loop with a large copper radiatorPrimoPrepControls the copper-driven pH swing
Neglected loop, heavy residue, pre-treatment will not cut itSystem SoapThen re-prep from the top
In what order

The sequence, start to fill

01Rad CleanRadiators on their own, before assemblycirculate 1 h in the radiator
02SysPrepWhole loop, lifts manufacturing debriscirculate 48 h
03PrimoPrepWhole loop, settles the pH swing a copper radiator introducescirculate 72 h

Refilling a loop that has already run coolant? System Reboot takes SysPrep's place in the middle, same 15 ml to a gallon, circulated 48 hours. PrimoPrep still follows it either way.

Inside the loop

Three things that ruin coolant

This is what every bottle above is defending against. The mechanism, the visible symptom, and the product that stops it.

Galvanic corrosion at every metal junction

Put copper and nickel in the same wet circuit and you have a battery. Electrons move from the less noble metal to the more noble one, and the nickel plating on your block starts to lift in flakes you will find in the reservoir six weeks later. Temperature accelerates it: a loop that idles at 45 °C corrodes faster than one that never leaves 30 °C.

Onset
Weeks to months
Reversible
Partly
Product
Liquid Utopia
The fix

Liquid Utopia carries a corrosion inhibitor package that plates a molecular barrier onto exposed metal. 15 ml per gallon of DI or distilled, under-dosing is worse than not dosing, because a partial film leaves anodic hot spots.

TUBE CROSS-SECTIONNickel plating lifting at the fin root
Why any of this

Coolant that has to clean will cloud.

Every block, radiator and fitting arrives with something on it, machining oil, casting flux, cutting debris. If the first thing to meet that residue is your coolant, the coolant spends its inhibitor package cleaning instead of protecting, and you see the result as a film at week three.

Prep takes about ninety minutes. Skipping it costs a teardown later, and the fluid usually gets the blame.

Changing coolants? Do this.

01Drain completely, from the lowest point
02Rad Clean through every radiator
03System Reboot if the old fluid was opaque
04Distilled rinses until runoff is clean
05SysPrep, then fill with the new coolant
PrimoChill

Keeping It Cool is the technical library of PrimoChill. Products ship from primochill.com.

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