Not sure if the mods want to make this a sticky too, but it was a nice day today, so I took the opportunity to change a customers' bearings outside.
It's all very well seeing some pics of smart, new bearings in a drum, but I thought it'd be beneficial to see something more like what you'll find if you change you own (i.e. a bit crusty, rusty and knackered looking!).
This customer uses his trailer as a launching trolley, so wasn't fussed about the brakes (hence the internal drum surface), but it certainly needed new bearings. It's not Haynes manual quality, as I'm not particularly good when it comes to photography and computers, but I'm sure you'll get the gist!....
This is a Peak 200 x 50 drum. Bearings and seal used were:
Inner cone: LM48548 / Inner cup: LM48510
Outer cone: L44649 / Outer cup: L44610
One drum, that looks like many of the rest of the boat trailers I've ever done!:
Weapons of choice: Right to left... ball pein hammer, large snap-on drift, small snap-on drift, normal punch/drift, large screwdriver. You can use the hammer with any of the other items to change a set of bearings, even the screwdriver if you're in a pinch. However, take care, as bearing cups are hard steel and can shatter if you're not careful. Metal in the eye is not something you want, take it from someone who knows!
The snap-on drifts are machined to a parabolic curve. This matches the curve of the bearing cup, so helps to stop chipping and splitting
The normal punch / drift is perfectly good too. You can pick these up from places like Machine Mart or Toolstation etc. for not much money at all, and should definitely be in an avid 'tinkerers' tool kit. Get the larger sort, as the smaller ones bend very easily and can slip off the bearing cup, causing you to thump your thumb and curse.
Keep, to one side, the original castellated nut and thrust washer, as these can be cleaned and re-used. However, always replace split pins with new.
So, first things first, get the old bearing cones out and clean up the inside of the drum boss, getting rid of any old grease and bearing remnant. This should reveal the cups to be knocked out and the purposely left 'breaks' in the cast lip of the drum, where the bearing cups sit. There'll be two for the rear bearing, exactly opposite each other, and the same for the front bearing cup.
And looking through the drum, from the other side, you can clearly see the 'break' again. This is where you start to strike the bearing cup with your drift.
Strike one side then the other, until the cup starts to move away from the lip.
Eventually it'll knock out. Flip the drum over and do the same for the other cup. Once knocked out, give them a quick clean and keep them to one side, as you'll see they come in handy for knocking the new cups in straight.
New race sat in the drum, ready to be knocked in: