Dynamo Bearing Replacement

[rsawatson]

Firstly, apologies if this is in the wrong forum on the messageboard - being a mechanical question about an electrical part, I couldn't decide - so have plonked it here.

I am pretty sure that the ball bearing in the drive end of the dynamo is shot; there is a noticeable 'grating' noise which changes according to engine speed, which isn't apparent when the fan belt is slackened off. The water pump was replaed < a month ago so I'm pretty sure it's not that.

Having dismantled the dynamo, the rivets on the bearing retaining plate need drilling out and subsequently replacing once the ball bearing has been renewed (according to the Haynes manual). Before I attempt this, can anyone advise on what size drill bit should be used to drill out the rivets and also what rivets (diameter, length or whatever - I have never used a rivet gun before) I should use when reassembling?

Many thanks in advance.

Ryan

[Alec]

Hello Ryan,

it doesn't really matter what size exactly as you are only removing the rivet head, you then drive the shank out. Probably in the order of 3\16" (5mm in foreign size). I would replace with suitable screws and nyloc nuts. The correct rivets are not done with a gun by the way.

Alec

[bmcecosse]

Is it worth all the hassle? And I thought dynamo ran in plain bearings anyway? Just pick up another dynamo for a £ (or 2 ) - or better still - an alternator !

[silloyd]

Pulley end has a roller bearing and the other has a bronze bearing.

My roller bearing was held in by a circlip and came out of the end casing with a little use of a 'persuader' but getting the bearing off the shaft was a nightmare!