Australian Land Rover Owners - View Single Post - smashing a gearbox bearing (7 bigish off site images)

Blknight.aus · #1 (**permalink**) 10th May 2008, 02:43 PM

ok heres the low res pics I have from brians gearbox rebuild. Its just the evidence that shows what happens to the bearing when you let a suzi idle or labour at low revs.

the front plate sans the oil pump... can you spot what else is missing?

The input shaft, notice the damage to the race the bearing was missing a ball and the damage to the main gear where the exiting ball has eaten a chamfer out of the teeth

another shot of the input shaft and the bearings. with the ones I pulled out of the box I was one ball short of a full bearing.

and this is the filter

Im pretty sure that the missing bearing is in there somewhere.

as Ive previously mentioned its the torque impulses that do the damage.

as the shafts change speed (and torque loadings) the angles of the teeth on the gearsets cause them to push back and forth against the bearings. As a general rule the slower the overall speed of the shaft when torque impulses are applied the more damage that gets done.

If youd like to see an anology of it go and get 2 wedges of hardwood smooth the angled faces place them all together so the bases of the wedges are 180degrees apart and the points are just overlapping place some plywood under and over the wedges and then put something heavy on top of it. (a series landrover works well)

If you now take 2 big hammers and bring them together on the wedges hard and at the same time you can jack the vehicle up as the wedges come together.

Thats the exact same principal that provides the thrust loading that does the damage, In effect it turns your lovely precision machined helical gears into precision jack hammers with the sole intent of destroying your bearings.

Im hoping Brian will come to the party and get a decent shot of the exterior bearing race thats taken the brint of the damage.