trailer bearing, how much grease to put where ?

simonfraser

simonfraser

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light use only to put 4.5 RIB in and out, no motorway travel.

one hub rumbles a bit. both have grease in, not packed tight. years old for sure.
there does not appear to be a grease nipple on either side of the bearing.

the big nut has a metal part indented to lock it to the shaft.
i can get the big nut off with some minor unbending of the rim, looks like that is done on purpose to stop it coming off.
any point in taking it apart further and getting more bearing grease, with a gun, inside ?

or shall i just squirt some in next to the shaft and put the cap back on ?

tnx.
 
simonfraser said:
light use only to put 4.5 RIB in and out, no motorway travel.

one hub rumbles a bit. both have grease in, not packed tight. years old for sure.
there does not appear to be a grease nipple on either side of the bearing.

the big nut has a metal part indented to lock it to the shaft.
i can get the big nut off with some minor unbending of the rim, looks like that is done on purpose to stop it coming off.
any point in taking it apart further and getting more bearing grease, with a gun, inside ?

or shall i just squirt some in next to the shaft and put the cap back on ?

tnx.
Click to expand...

You have to become fully committed, completely undo the large "castle" nut and slide the hub assembly off. The smaller outer bearing and washer that sits behind the castle nut will just fall out, the larger inner bearing will need to be tapped out with a long piece of timber dowl or similar to not damage it in case it can be reused.
Wash off the grease with kerosene or petrol in a dish with an old paint brush and inspect for any corrosion or scoring on the bearing rollers or retainers.
Repack the new or reused bearings with new grease, making sure the grease is pushed in deep between the rollers (big dob in the palm of your hand, while pushing the bearing hard into it with the other hand).
Then reverse the process, making sure the castle nut is done up firmly to start with then backed off slightly until you feel the slightest bit of play or looseness in the hub by pulling it backwards and forwards.
Use proper tight fitting disposable gloves if you don't like getting your hands dirty, because this is seriously messy work, but essential for bearing maintenance.
 
Which make is the trailer? It sounds like an SBS. If you don't have bearing savers and have used it as a launching trolley I would tend to agree with one of the other posters that the bearings are shot. I don't think you have a castellated nut, if you did, you would have a split pin holding it on, pull the pin and the nut would spin off. From the sound of it your trailer has a single bearing which, the manufacturer says is a sealed bearing, but unfortunately there is no such thing. It will be held on by a nut which should have a torque of about 300ft lbs then staked in to be sure it holds. Jack up the trailer, spin the wheels and if it rumbles badly, you'll have to replace the bearings. If you are going to continue to use it as a launching trolley then just repack the bearings until you have to trail it somewhere, then you will have to replace them, otherwise you might be in for an expensive repair.
 
capnjack said:
Which make is the trailer? It sounds like an SBS. If you don't have bearing savers and have used it as a launching trolley I would tend to agree with one of the other posters that the bearings are shot. I don't think you have a castellated nut, if you did, you would have a split pin holding it on, pull the pin and the nut would spin off. From the sound of it your trailer has a single bearing which, the manufacturer says is a sealed bearing, but unfortunately there is no such thing. It will be held on by a nut which should have a torque of about 300ft lbs then staked in to be sure it holds. Jack up the trailer, spin the wheels and if it rumbles badly, you'll have to replace the bearings. If you are going to continue to use it as a launching trolley then just repack the bearings until you have to trail it somewhere, then you will have to replace them, otherwise you might be in for an expensive repair.
Click to expand...

tnx, that's what it is, staked, now i have the correct part name. indeed SBS trailer.

ok, how to 'unstake' it ? or just push the grease round it as its only used as a launching trolley ?
 
any rumbling bearing needs closer inspection. It means that either balls/needles are rusted/flat-spotted from being static under heavy load, or that the bearing face/cage is pitted. In both cases it is unreliable and is at risk of collapse and needs replacement. Forcing new grease in is only putting off the collapse day a bit. Wheels should spin without any rumbling at all.
 
simonfraser said:
tnx, that's what it is, staked, now i have the correct part name. indeed SBS trailer.

ok, how to 'unstake' it ? or just push the grease round it as its only used as a launching trolley ?
Click to expand...

If it is a "sealed" bearing that has lost it's grease, you won't have much joy pushing grease back in - they can't be dismantled like a normal bearing with a separate race. All you will be effectively is smearing grease over the outside.

If all you are doing is pushing the trailer around a yard and up and down the ramp, no problem, but if you are going any more than a few hundred yards at anything above walking pace, you run the risk of the bearing overheating, seizing and breaking up.
 
Hi Simon
Glad I got the make right, so now it is easier to get to the how to bit. I often get these questions on my boat forum, there are a lot of guys like mlines who has posted and who have serviced there own trailers and understand how they work. SBS trailers do use sealed bearings similar to car wheel bearings. As I said previously no bearing is truly sealed, what they actually mean is that there is a rubber seal to keep out dust and muck and that the bearing is sealed inside. I agree with other posters that these sort of bearings will not take grease, unfortunately if they are shot you wont be able to get any grease in them. There are pdf's on the SBS boat trailer website.
You asked how to remove the stake, flanged nuts are widely used, I have them on my Land Rover, you can just twist the nut off, but the stake will lift with a screwdriver inserted and with a little tap from a hammer. I can't find the torque setting but it is massive so getting the nuts off might be a struggle unless you have a large lever.
I think if you are only moving the trailer around the boatyard and check the wheels spin regularly, it may be worth considering changing the bearings at the end of the season. If on the other hand you want to trail it anywhere, you absolutely should change them.
Hope this helps.
 
Tnx, I shall put the caps back on as I only walk / tractor it a few yards.
But, now I have your attention, how do I find out what to order as and when the time comes ?
I can't see any marks on the casing at all.
I have a long torque bar for my car wheels so I recon I can get the castle nut off, famous last words ......
 
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