bearing buddies dynamics
Hi guys,
My trailer (tandem) came wiht bearing buddies; I have a question about the physics of these B/Buddies that I am hopeful someone wiht more workshop sense than myself could answer:
If the principle of operation of the B/B's is that a 3PSI pressure exerted through a grease ball onto the outer bearing will prevent water ingress into the bearing when plunging a hot hub into cold water, why is it that they keep needing topping up with grease? By my understanding of the mode of operation, grease should not be consumed, only moved ( marginally) by a pressure of 3PSI max.
I do get some grease onto my rims over time which would suggest that the inner bearing seals are not sealign properly - this may be the case, though they were carefully fitted and the bearings have always been in A1 condition when changed ( annually).
Any wise pointers appreciated, thank you
tim-o
Posts: 4657
Date Joined: 24/05/11
Bearing buddies are overated
Bearing buddies are overated imo. If you are running marine seals, chances are the bb is pumpin the grease out. Regular spring lip seals would probably cope with a little pressure on the back of them better. Cant go wrong with properly packed bearings with regular seals and dust caps, Im happy to see a bit of grease around the seal externally, means the hubs are packed well and adds to the protection, just dont dunk them straight after a long drive on a hot road and check/repack atleast once a year
I am, as I've said, merely competent. But in an age of incompetence, that makes me extraordinary.
Devo1965
Posts: 120
Date Joined: 29/09/13
Bearing buddies
Agree that they are over-rated, Make a mess, sometimes leak at spring piston end, had a couple fall off due to weight on rough tracks, overall I had more water ingress than standard dust caps, If you top up grease after every run you may have a better success, but probably more mess.
For me dust caps work find on both my boat trailers, yearly bearing checks, also think if every few trips you removed the dust cap, put bearing buddie on, pumped a few shots of fresh grease in and then put the dust cover back on, might give bearings some more life.
Devo1965
Paul H
Posts: 2104
Date Joined: 18/01/07
Had new bearing put in in
Had new bearing put in in march (and bearing buddies put back on) headed for Smoky bay and 100km into trip saw right outer buddie fly off onto the verge, and that was on a flat bitumen road - couldn't find it - good thing no cars in opposite direction at the time hate for it to have gone through someone's windscreen. - packed the hub with grease and put a dust cap on. packed it again before launching and has been good since, just going to get rid of them as bearings are easier to change/service without them.
Youtube Channel - FishOnLine Productions
https://www.youtube.com/channel/UCbUVNa-ViyGm_FTDSv4Nqzg/videos
WALLABOK
Posts: 52
Date Joined: 05/01/14
Cheap caps over BB's
I bought a set of cheap dust caps from Super cheap and cut 4 small slots onto the lip with a 1mm blade 90 degrees to each other. ,my problems was solved. I tapped them in and applied silicon before knocking in. I have a 2.9t boat that travels everywhere ( excluding trailer weight.
Wallabok
rocklobster
Posts: 363
Date Joined: 27/12/09
another trick is to use a
another trick is to use a bead of sealant on the lip of the bearing buddy / dust cap and also around the edge of the inner seal. I used to work for a skiboat shop and always found the bearings had corroded from dunking a hot hub into cold water causing the water to be drawn into the hub assy. tim-o's onto it, old fashioned spring type seals work better than marine seals