I think I finally figured this out. After hours of searching and reading I found that our old 2 strokes like SCA2 type antifreeze which is Ethylene Glycol based which is what I have in my Fleet Charge (Cummins) and Fleet Guard (Peak) antifreeze. (Both are red in color). The 3 way test strip for my application only regards the top and bottom result on the strip. The molybdate pad on the middle of the strip does not apply for SC2 test. I found this out from this page:
https://www.cumminsfiltration.com/sites/default/files/pdf_archive/pdfs/product_lit/americas_brochures/LT15626.pdf That is not shown on the test strip package.
I also found that Detroit Diesel states that a color change on the middle of the strip is verbotten. The molybdate result is for an SCA4 type additive. See item 4 below:
___________________________________________________________________________________
COOLANT SELECTIONS
All information subject to change without notice.
7SE298 0106
Copyright © 2001 DETROIT DIESEL CORPORATION
18
SCA Test Procedures
Nitrite concentration is an indication of the overall coolant inhibitor concentration in non-OAT
formulations. Coolant must be tested for nitrite concentration at the regular intervals listed in
Table 9.
Power Trac (which is Detroit Diesel brand)
3-Way Test Strips (or equivalent) are recommended. Nitrite levels must be
within the ranges listed in Table 7 and listed in Table 8.
Use Detroit Diesel
Power Trac
3-Way Coolant Test Strips to measure nitrite and glycol
concentrations. Refer to section titled “
POWER COOL
ENGINE PRODUCTS” for part numbers.
Cavitation/corrosion protection is indicated on the strip by the level of nitrite concentration.
Freeze/Boil-over protection is determined by glycol concentration.
Use the test strips as follows:
1. Dip the strip into coolant for one second. Remove and shake briskly to eliminate excess fluid.
2. Immediately compare end pad (% Glycol) to the color chart on the container.
3. Sixty seconds (one minute) after dipping, compare the nitrite pad.
4. Color change of additive indicator (middle pad) indicates the presence of inhibitor that is not approved
by Detroit Diesel.
For best results make the tests while the coolant is between 50°-140°F (10.0°-60°C). Wait at least
60, but not longer than 75 seconds before reading the nitrite level. Promptly replace and tighten
container cap after each use. Discard unused strips if they have turned light pink or tan.
A factory coolant analysis program is available through authorized Detroit Diesel service outlets.
Refer to section titled “
POWER COOL
ENGINE PRODUCTS” for part numbers. To verify coolant
acceptability, submit a sample for coolant analysis every three (3) years, 300,000 miles, or 6,000
operating hours, whichever comes first.
NOTICE:
Failure to properly maintain coolant with SCA can result in damage to
the cooling system and its related components. Conversely, over
concentration of SCA inhibitor can result in water pump seal leaks and
poor heat transfer, leading to engine damage. Always maintain
concentrations at recommended levels.
Do not use traditional SCAs
with NOAT coolant
_____________________________________________________________________________________
So, my test result is good as my Nitrite level is in column F intersecting row 0 as directed by the instructions which is in the middle of the acceptable range. I am good to go. The Detroit coolant selection guide I found is copyright 2001. I hope it applies to my 1985 engine as well. I can't find any other guide to go from.
Unless you guys see something wrong in my synopsis I hope I can put this to rest.
David
