Question

When greasing a U-joint on a driveshaft, grease only exits from three of the four journal seals on the trunnion. What should you do first?

a) Loosen the journal cap and try again.
b) Heat the trunnion with a rosebud.
c) Leave it; three of four journals are good enough
d) Replace the U-joint.

Answer 1

When greasing a U-joint on a driveshaft, it is normal for grease to only exit from three of the four journal seals on the trunnion. If the U-joint is functioning properly and there are no signs of damage or wear, there is no need to take any immediate action.

Step-by-step explanation:

When greasing a U-joint on a driveshaft, it is normal for grease to only exit from three of the four journal seals on the trunnion. The purpose of the journal seals is to retain the grease and prevent it from leaking out. If the U-joint is functioning properly and there are no signs of damage or wear, there is no need to loosen the journal cap or heat the trunnion.

If the U-joint is not showing signs of damage and three of the four journal seals are successfully retaining the grease, there is no need for any immediate action. Three out of four seals is considered to be good enough for the proper lubrication of the U-joint.