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profqwerty - n/a
1-Sep-07, 07:33 PM
I'm just putting together a drive-hub etc, and the outer races on the bearings are extremely tight fit into the drivehub. inner races are fine on the shaft bit. Is this normal? it's about 17C or so.



I've tried WD-40 / thin oil, but it's still tight. I can hit it with a rubber mallet, but this only works til it's flush.



Can anyone recommend something that fits onto one of these races?



Is it recommended NOT to put the bearing together and hit it (it's a bigger target)??



thanks!

toby

andycollins - n/a
1-Sep-07, 07:38 PM
I got the bits for mine from K&M and they too where a tight fit, I don't think this is by chance. You need a good fit to stop the races fretting in the hub.



I got mine to go in by heating the hub gently in the oven. After 10mins or so the races just dropped in as sweet as anything.





Cheers.



Andy.

profqwerty - n/a
1-Sep-07, 08:23 PM
Same from K&M. As I have already got them half in, there is no way it can be gotten out, so if i heat both together will the aluminium hub expand more than the steel race to the point that it will go in?

thanks!

andycollins - n/a
1-Sep-07, 08:30 PM
Yes, the ali will expand more and all will be well http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif



Take a bit of care to make sure the races stay square down the bore but I doubt there will be enough clearance for them to twist anyway.







Cheers.



Andy.

mick - n/a
1-Sep-07, 08:55 PM
Sounds normal to me, i have put 2 lots in and had them pressed in using a big buterfly press, you could heat and freze the other one and using a good fitting driffed ,driff it home , good luck

profqwerty - n/a
2-Sep-07, 08:57 AM
200C for 10 mins. The races went in peeeerfectly http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif



To grease them, i'm assuming a thin / thick layer of general grease onto the outer race, then fit the rest of it and spin it a few times?



Also, Does anyone know how much oil is recommended to be put into one of K&M's lower bearing blocks?



thanks!

toby

kevinf - n/a
2-Sep-07, 12:26 PM
There is a small bolt in the side of the bearing block, remove this and fill until oil comes out of the hole. Don't forget to put the bolt back in or it makes a right mess!