ASTM D4290 for determining leakage tendencies of automotive wheel bearing grease
ASTM D4290 standard test method for determining the leakage tendencies of automotive wheel bearing grease under accelerated conditions
6. Apparatus
6.1 Test Assembly (Figs. 1 and 2).
6.1.1 Custom-made Wheel Hub-Spindle-Bearing Assembly (Fig. 3).

6.1.2 Oven, electrically heated by 1800 watt heater, thermostatically controlled to maintain spindle temperature at 160 more or less 1.5°C.

6.1.3 Spindle Drive Motor, 1/4 hp, 120 volts dc with 1725 rpm speed control for the hub; motor torque is indicated by a meter equipped with an adjustable, automatic cutoff.

6.1.4 Fan Drive Motor, 1/30 hp, 120 v dc, 1550 rpm.

6.2 Motor speed, oven temperature, spindle temperature, time cycles and torque are controlled or monitored, or both, by accessory equipment.

6.3 A grease slinger has been added since the original design of the apparatus. Fig. 4 shows the slinger used for the hub of Koehler and Pam apparatus.

NOTE 2 - The slinger was developed to prevent grease from creeping along the hub and being slung off past the grease collector. Greases that crept during the test can lead to erroneously low results. Addition of the slinger will not affect the precision data in Section 13 because none of the round-robin greases exhibited grease creepage.

6.4 Balance, having a minimum capacity of 100 g and minimum sensitivity of 0.1 g.

7. Test Bearings
7.1 Use LM67048-LM67010 and LM11949-LM11910 (AFBMA Standard 19) inboard and outboard bearings respectively.

8. Reagents and Materials
8.1 Penetone ECS4 ( Warning - Combustible. Vapors can be harmful.)

8.2 n-Heptane - reagentgrademinimumpurity. (Warning - Flammable. Harmful if inhaled.)

8.3 Isopropyl Alcohol - reagent grade minimum purity. (Warning - Flammable.)

8.4 Stoddard Solvent or Minerals Spirits - reagent grade (Warning - Combustible. Vapors may be harmful.)

8.5 SAE 10W Engine Oil.

8.6 00 Grade Steel Wool.

9. Preparation of Bearings
9.1 Carefully remove new bearings (cups and cones) from their packages and place in a suitable clean container. Wash with n-Heptane to remove all rust preventative.

9.2 Repeat washing with n-Heptane two additional times to be certain all rust preventative has been removed. Use a clean beaker each time.

9.3 Drain n-Heptane from the bearings and set them on a clean, lint-free cloth or towel to air dry.

NOTE 3 - Cleaning may be facilitated by the use of a sonic cleaner.