TM 5-3895-346-14
ENGINE OVERHAUL
COOLANT
SPECIFICATIONS
INHIBITOR SYSTEMS
An inhibitor system (Fig. 3) is a combination of chemical compounds which provide corrosion protection, pH
control, and water softening ability. Corrosion protection is discussed under the heading Corrosion Inhibitors.
The pH control is used to maintain an acid free solution. The water softening
Inhibitor Compatibility
Corrosion
Complete
Ethylene
Inhibitor or
Inhibitor
Inhibitor
Glycol
Base
Inhibitor System
Type
System
Water
Antifreeze
Sodium chromate
Chromate
No
Yes
No
Potassium dichromate
Chromate
No
Yes
No
Perry filter elements:
5020 (type OS)
Chromate
Yes
Yes
No
S-453 (Spin-on)
Chromate
Yes
Yes
No
S-373 (Spin-on)
Nonchromate
Yes
Yes
Yes
5070 (type OS)
Nonchromate
Yes
Yes
Yes
S-473 (Spin-on)
Nonchromate
Yes
Yes
Yes
Lenroc filter element
Nonchromate
Yes
Yes
Yes
Fleetguard filter elements:
DCA (canister)
Nonchromate
Yes
Yes
Yes
DCA (Spin-on)
Nonchromate
Yes
Yes
Yes
AC filter elements:
DCA (canister)
Nonchromate
Yes
Yes
Yes
DCA (Spin-on)
Nonchromate
Yes
Yes
Yes
Luber-Finer filter elements:
LW-4739 (canister)
Nonchromate
Yes
Yes
Yes
LFW-4744 (spin-on)
Nonchromate
Yes
Yes
Yes
Nalcool 2000 (liquid)
Nonchromate
Yes
Yes
Yes
Perry LP-20 (liquid)
Nonchromate
Yes
Yes
Yes
Sy-Cool (liquid)
Nonchromate
Yes
Yes
Yes
Lubercool (liquid)
Nonchromate
Yes
Yes
Yes
DuBois Chemicals IWT-48
Nonchromate
Yes
Yes
Yes
(liquid)
Norman Chemicals C15
Nonchromate
Yes
Yes
Yes
(liquid)
Aqua-Tane (liquid)
Nonchromate
Yes
Yes
Yes
Important: Do not use methoxy propanol base antifreeze in Detroit Diesel engines.
Figure 3. Coolant Inhibitor Chart
407
