If you were told a wheel bearing had been greased , after roughly1500km would the grease go black in the bearing and still be clean in the middle of the hub ?
Lance C
justcruisin01 said
03:44 AM Mar 14, 2013
Olley46 wrote:
A question for the brainy
If you were told a wheel bearing had been greased , after roughly1500km would the grease go black in the bearing and still be clean in the middle of the hub ?
Lance C
A little bit vague with info but, Grease can come in verious colours from yellowish, green, blue to black. depending on the brand & type.
Assuming that the bearing had been repacked, the grease in the actual bearing will discolour with use, where as the grease in the centre of the hub never moves so will remain the same as when fitted.
This is why manufactures these days never fill the centre of the hub with grease, they put it down to better cooling. I have dismantled many & they have never seen grease in the centre of the hub.
I stick with the way I was taught to repack bearings, that was to place plenty in the hub & thats the way I run mine.
JC.
Olley46 said
04:16 AM Mar 14, 2013
Thanks JC you have answered my question, I thought maybe once the grease heated up it may run through the hub to both bearings, it was yellow in the centre and black in the bearings,anyhow I have repacked the bearings with Nulon Xtreme performance high temp water resistant grease red in colour,ready for the big trip coming up.
Lance C
03_troopy said
02:52 AM Mar 15, 2013
Do you use the "scoop the grease through the bearing from the palm of your hand" method, or do you have a grease bearing packer? The only problem with the scooping method is that sometimes you get tiny air bubbles forced into the grease. I found the white plastic cone type packers that tighten either side of the bearing with a nipple on the threaded shaft seem to work pretty well.
Olley46 said
05:35 AM Mar 15, 2013
03_troopy wrote:
Do you use the "scoop the grease through the bearing from the palm of your hand" method, or do you have a grease bearing packer? The only problem with the scooping method is that sometimes you get tiny air bubbles forced into the grease. I found the white plastic cone type packers that tighten either side of the bearing with a nipple on the threaded shaft seem to work pretty well.
Hi 03troopy
I did the old grease in the palm trick made shore the grease was well and truly worked through the bearing,I feel that I have done the job satisfactory , time will tell.
Lance C
hako said
09:29 PM Mar 18, 2013
Olley46 wrote:
A question for the brainy
If you were told a wheel bearing had been greased , after roughly1500km would the grease go black in the bearing and still be clean in the middle of the hub ?
Lance C
G'Day Olly, not brainy but when I greased our low mileage (3500km) Avans brearings about 2 months ago, the actual grease within the rollers was virtually the same colour as the greased pached inside the hub - almost no discolouration. If mine were black I'd suspect the bearing may have overheated or the bearing surfaces have had rust or some other contamination on them which has made the grease go black. I would rinse all the black grease off them using petrol and then when dry I'd closely inspect the rollers and the bearing cups for any signs of wear - both should ideally be mirror smooth. Use a magnifying glass.
Engine oil goes black due to the byproducts of combustion (carbon)....no combustion in wheel bearings so apart fromn the above I cannot see why it would go black.
Good Luck.
Scotty01 said
10:40 PM Mar 18, 2013
The discolouration of the grease is mostly caused by water ingression, heat or wear on the bearings, it depends a lot on just what sort of grease you use. Wheel bearings should always be packed with high melting point stuff that is also classed as waterproof or resistant. In the old days yes the hubs were packed with grease in the center but the better quality and higher melting point have made this redundant. The center of the hub should have a thin coating of grease purely to protect from rust scale forming if water happens to find it way in. Rust scale will quickly lead to bearing and or seal failure.
Olley46 said
03:19 AM Mar 19, 2013
hako wrote:
Olley46 wrote:
A question for the brainy
If you were told a wheel bearing had been greased , after roughly1500km would the grease go black in the bearing and still be clean in the middle of the hub ?
Lance C
G'Day Olly, not brainy but when I greased our low mileage (3500km) Avans brearings about 2 months ago, the actual grease within the rollers was virtually the same colour as the greased pached inside the hub - almost no discolouration. If mine were black I'd suspect the bearing may have overheated or the bearing surfaces have had rust or some other contamination on them which has made the grease go black. I would rinse all the black grease off them using petrol and then when dry I'd closely inspect the rollers and the bearing cups for any signs of wear - both should ideally be mirror smooth. Use a magnifying glass.
Engine oil goes black due to the byproducts of combustion (carbon)....no combustion in wheel bearings so apart fromn the above I cannot see why it would go black.
Good Luck.
Hi hako
the wheel bearings were supposed to of been greased when I bought the van,I just re greased them myself ,they were washed in petrol and checked for heat marks and case hardening wear all were good been repacked with Nulon extream grease high tempature water proof ,and new seals fitted ,as good as new I hope.
Lance C
Delta18 said
07:27 PM Mar 19, 2013
Scotty01 wrote:
The discolouration of the grease is mostly caused by water ingression, heat or wear on the bearings, it depends a lot on just what sort of grease you use. Wheel bearings should always be packed with high melting point stuff that is also classed as waterproof or resistant. In the old days yes the hubs were packed with grease in the center but the better quality and higher melting point have made this redundant. The center of the hub should have a thin coating of grease purely to protect from rust scale forming if water happens to find it way in. Rust scale will quickly lead to bearing and or seal failure.
What Scotty said!
Filling the hub with grease is just a waste of grease, it does nothing.
Just wash the cones with petrol, or, to be safer Kero is just as good, then rinse with water then ideally, compressed air to dry thoroughly.
DO NOT ALLOW THE CONES TO SPIN UNDER THE COMPRESSED AIR!!!!! They will get damaged.
Check the rollers for scoring, pitting or blueing which indicate overheating.
Pack with HT grease and re-assemble being careful not to over-tighten the castellated nut. Here is how I was taught to tighten the nut.....Using a 12" shifter tighten the nut whilst rotating the wheel, get it quite tight and spin the wheel 15 - 20 revolutions. Now loosen the nut until - holding the shifter at 1 o'clock position the shifter can fall under it's own weight to about 4'oclock. That is tight enough. Find the closest hole to re-fit the split pin.
This sounds complicated but really it is not.
Cheers Neil
hako said
04:39 PM Mar 20, 2013
Neil - you say "Now loosen the nut until - holding the shifter at 1 o'clock position the shifter can fall under it's own weight to about 4'oclock. That is tight enough. Find the closest hole to re-fit the split pin." - do you mean find the closest hole to the 1 o'clock or 4 o'clock position? Thanks.
Delta18 said
06:18 PM Mar 20, 2013
hako wrote:
Neil - you say "Now loosen the nut until - holding the shifter at 1 o'clock position the shifter can fall under it's own weight to about 4'oclock. That is tight enough. Find the closest hole to re-fit the split pin." - do you mean find the closest hole to the 1 o'clock or 4 o'clock position? Thanks.
What happens is, when the shifter stops falling, THAT is the sweet spot. Move the nut now only enough to insert the pin.
Hope that helps.
Neil
hako said
03:54 AM Mar 21, 2013
Delta18 wrote:
hako wrote:
Neil - you say "Now loosen the nut until - holding the shifter at 1 o'clock position the shifter can fall under it's own weight to about 4'oclock. That is tight enough. Find the closest hole to re-fit the split pin." - do you mean find the closest hole to the 1 o'clock or 4 o'clock position? Thanks.
What happens is, when the shifter stops falling, THAT is the sweet spot. Move the nut now only enough to insert the pin.
Hope that helps.
Neil
Thanks Neil - makes sense ...using a shifter more or less as a tension wrench would ensure you always have the same pre-load so that's a good tip I reckon.
A question for the brainy
If you were told a wheel bearing had been greased , after roughly1500km would the grease go black in the bearing and still be clean in the middle of the hub ?
Lance C
A little bit vague with info but, Grease can come in verious colours from yellowish, green, blue to black. depending on the brand & type.
Assuming that the bearing had been repacked, the grease in the actual bearing will discolour with use, where as the grease in the centre of the hub never moves so will remain the same as when fitted.
This is why manufactures these days never fill the centre of the hub with grease, they put it down to better cooling. I have dismantled many & they have never seen grease in the centre of the hub.
I stick with the way I was taught to repack bearings, that was to place plenty in the hub & thats the way I run mine.
JC.
Thanks JC you have answered my question, I thought maybe once the grease heated up it may run through the hub to both bearings, it was yellow in the centre and black in the bearings,anyhow I have repacked the bearings with Nulon Xtreme performance high temp water resistant grease red in colour,ready for the big trip coming up.
Lance C
Hi 03troopy
I did the old grease in the palm trick made shore the grease was well and truly worked through the bearing,I feel that I have done the job satisfactory , time will tell.
Lance C
G'Day Olly, not brainy but when I greased our low mileage (3500km) Avans brearings about 2 months ago, the actual grease within the rollers was virtually the same colour as the greased pached inside the hub - almost no discolouration. If mine were black I'd suspect the bearing may have overheated or the bearing surfaces have had rust or some other contamination on them which has made the grease go black. I would rinse all the black grease off them using petrol and then when dry I'd closely inspect the rollers and the bearing cups for any signs of wear - both should ideally be mirror smooth. Use a magnifying glass.
Engine oil goes black due to the byproducts of combustion (carbon)....no combustion in wheel bearings so apart fromn the above I cannot see why it would go black.
Good Luck.
The discolouration of the grease is mostly caused by water ingression, heat or wear on the bearings, it depends a lot on just what sort of grease you use. Wheel bearings should always be packed with high melting point stuff that is also classed as waterproof or resistant. In the old days yes the hubs were packed with grease in the center but the better quality and higher melting point have made this redundant. The center of the hub should have a thin coating of grease purely to protect from rust scale forming if water happens to find it way in. Rust scale will quickly lead to bearing and or seal failure.
Hi hako
the wheel bearings were supposed to of been greased when I bought the van,I just re greased them myself ,they were washed in petrol and checked for heat marks and case hardening wear all were good been repacked with Nulon extream grease high tempature water proof ,and new seals fitted ,as good as new I hope.
Lance C
What Scotty said!
Filling the hub with grease is just a waste of grease, it does nothing.
Just wash the cones with petrol, or, to be safer Kero is just as good, then rinse with water then ideally, compressed air to dry thoroughly.
DO NOT ALLOW THE CONES TO SPIN UNDER THE COMPRESSED AIR!!!!! They will get damaged.
Check the rollers for scoring, pitting or blueing which indicate overheating.
Pack with HT grease and re-assemble being careful not to over-tighten the castellated nut. Here is how I was taught to tighten the nut.....Using a 12" shifter tighten the nut whilst rotating the wheel, get it quite tight and spin the wheel 15 - 20 revolutions. Now loosen the nut until - holding the shifter at 1 o'clock position the shifter can fall under it's own weight to about 4'oclock. That is tight enough. Find the closest hole to re-fit the split pin.
This sounds complicated but really it is not.
Cheers Neil
Thanks.
What happens is, when the shifter stops falling, THAT is the sweet spot. Move the nut now only enough to insert the pin.
Hope that helps.
Neil
Thanks Neil - makes sense ...using a shifter more or less as a tension wrench would ensure you always have the same pre-load so that's a good tip I reckon.