Trailer wheel bearings

[fizzy]

Possibly not what you want to hear now it's all back together but is the plastic bit supposed to protect the oil-seal on the back of the hub? There's usually something to act as a bit of a shield for that seal whether it's metal or plastic. The ones I've messed with have all been just a disc rather than the top-hat shape you've got but I don't know what shape the stub axle is back there.

I tried that as well - no it is bigger diameter there. Just dismantled another one and no plastic. Possibly off something else just a coincidence it was a perfect fit on the stub!

 

[Sean]

bin the cotter and fit an R pin

 

[fizzy]

All done now thanks.
That plastic part was a red herring - going to have it for supper tonight!