Crunch, grind and scrape from dynamo!

[an_avenger]

I've noticed a few weird noises from my dynamo recently. Every time I crank my engine I hear at a particular point a grinding noise coming from the dynamo - does this mean the bearings are worn and can you still get them? I've never adjusted the fan-belt since I bought the car (March 2002) and so haven't payed much attention apart from the quick lubrication here-and-there! Any ideas friends....?

[Willie]

Lo, with a dynamo the fan belt should be set so that it is
JUST possible to turn the fan blades by hand when engine
is stationary! The rear bearing,which is a plain bush, is
liable to sieze up if not lubricated often enough. This bush
is available but the tricky bit is removing the old one. Regardless
of the possible faults, an exchange reconditioned dynamo
is very reasonably priced, especially if you can collect it and
avoid postage.
Willie

[an_avenger]

Great - after investigating prices you're right a recon. would probably be the easier option esp if the car is used all the time!

[rayofleamington]

I had a similar thing on a 72 saloon that I'd just bought as a quick do-er upper.
The dynamo was squeeling and grinding so the previous owner had taken the fanbelt off as it sounded awful and he didn't want to put me off taking the car.. Needless to say I wasn't pleased when I put a new fanbelt on.

I tried lubricating the rear bearing as a short term measure, but it's been going for a few months now without even a squeak!

[rob_dewing]

If you do fit a new dynamo don't forget to oil the rear bearing before you fit the dyanamo otherwise it will wear out in a couple of thousand miles. Trickle oil into the hole marked 'oil' until the felt pad is saturated. It's best to do this when the dyanamo is off the car so you can stand it on end for ease of access, and do it a few hours before running the dyanamo for the first time as the bearing is sintered bronze which the oil takes a while to permeate into.

The bearings are not that hard to remove as being sintered they are quite crumbly if you knock a sharp ended flat screwdriver in between the outside of the bearing and the bore of the end cap that it sits in - they will break out bit by bit particularly if you start on the worn thin side.

But as you say not expensive to buy and you can still get them from good motor factors, on 24hr special order if not in stock. I think some of the recons are of dubious quality though. I've had some only last a short time e.g. Sovereign and now go for Lucas or Bosch branded exchanges (yes, the Bosch box contains a Lucas branded dynamo!)