90 Quattro 20V L5-2309cc 2.3L DOHC (7A) (1990)
Coolant: Technical Service Bulletins
Antifreeze Testers - Accuracy
Group:
19
Number:
91-02
Date:
10/31/91
Subject:
Accuracy of Antifreeze Testers
Model(s):
All
All M.Y.
Float type antifreeze testers, with age, may read incorrectly. Antifreeze and corrosion inhibiting additives stick to the float making it
heavier, causing inaccurate protection level readings.
Calibrate your tester using a 50/50 mixture of antifreeze and water. It must read -34~ F. If your tester is not accurate, put a mark (or paint
dot) to indicate the location of -34~ F.
With this information you will be able to continue using your tester and make accurate antifreeze protection level test.
Graph shows the freezing points of various antifreeze/water concentrations.