Alternator Bearings

[tobyd]

Anyone ever replaced the bearings on an alternator?

 

Recently had to replace my 4 year old GSF refurb brandless one due to the many bad noises it made.

 

Wondering how much of the (wince) £100 i could have saved by redoing them myself (never tried before) or if its cheap to get an alternator place to do it?

 

cheers

 

toby

[holbeck]

 

There was another thread about this, but because I iz idiot I couldn't link to it so I cut and pasted what I posted then.

 

 

 

 

<<Yes, it's possible. you will need access to a press and suitable mandrels. The bearing is a standard automotive roller bearing available from bearing retailers, but not available as a service item from Ford.

 

 

 

Ford used a variety of different alternators with the zetec engine, depending on vehicle line or spec,

 

Escorts were mostly Mitsubishi

 

Mondeo's -Bosch. .

 

Focus early ones were Magneti Marelli and later Denso.

 

 

 

Ford (in the 1990's) generally specified all manufacturers to use Koyo bearings in alts supplied to Ford

 

 

 

 

 

For a Mitsubishi type, there are 4 long bolts holding the case together, these can be removed and the case can then be split. The rear half consists of the rear casting, brushbox, regulator / rectifier and stator.

 

 

 

The front, has pulley, rotor and front casing including bearing.

 

The pulley must be removed and the rotor withdrawn from the bearing. The bearing itself is secured behind a thrustplate, once this is removed, the bearing can be pressed out. read the code on the bearing and a factor will be able to supply a replacement.

 

 

 

To re-assemble the brushes must be retained in the brushbox to allow for the rotor shaft to be inserted, there's a handy hole in the casing to push a bit of wire through to do this.

 

 

 

Job jobbed!>>

[tobyd]

That easy eh? I'd need to buy the tool for the front pulley, some form of VW 33.3 torx but otherwise just break open and shake the bits out. Should have tried, looked more complex than that.

 

i watched some people bash the old bearing out with a hammer and then some other people saying this would distort the casing and all would be to ruin?

 

thanks!

[holbeck]

I wouldn't recommend hammering..... unless you are very gentle and you use a suitable offcut of steel bar as a mandrel.

[tobyd]

hitting it with a lump hammer + socket didn't look such a good idea...

 

Wondering how much extra replacing duff bits in alternators/starters/similar is over taking them to be repaired, not having a press or mandrill puts a lot of these sorts of repairs in the VW cambelt fitting kit region where the few times ill ever get the use the thing doesn't ever recoup the cost of a garage doing it?

 

£100 alternator is half the cars direct-line valuation...

[holbeck]

Maybe the way forward is to find a local engineering company (or blokes therein).

 

You dismantle it / identify the bearing - they press out / press in the bearing for beer tokens.

[holbeck]

Just a stab in the dark that these guys are near you, but they have the right capabilities.

 

http://www.needhamfabrications.co.uk/

[tobyd]

Didn't think of that sprawling industrial estate full of shops like this a 5 minute walk down the road...

 

know for next time though. cheers

 

toby

[overrun]

hitting it with a lump hammer + socket didn't look such a good idea...

 

Wondering how much extra replacing duff bits in alternators/starters/similar is over taking them to be repaired, not having a press or mandrill puts a lot of these sorts of repairs in the VW cambelt fitting kit region where the few times ill ever get the use the thing doesn't ever recoup the cost of a garage doing it?

 

£100 alternator is half the cars direct-line valuation...

My MR2 alternator developed the '3 lights of death',so was not long for the world.

 

The cam cover gasket has been leaking oil into it, and I presume (as the wiring connection and plug are fine) that the brushes didn't appreciate this. Or the voltage regulator has just packed in.

 

I split the case and matched the brush pack and reg to a new item from eBay.com.

For only £20, delivered, it's worth a shot IMO.

 

OP, bust it open and match the bearings.

[metrognome]

Find an electric motor repair/rewind outfit.

 

They will piss it.

[Junkman]

Every time I refurbed an alternator, it didn't work afterwards.

So I gave up on it a long time ago.

[Andrew353w]

I always use an exchange repairer, who guarantees his work for a year and I've never had cause to use it! He takes the broken one in & normally has an exchange one in stock. if not, he usually has the original one fixed in 24-48 hours & it's miles cheaper than buying a new one from a dealer or a factor. On balance, better value then attempting the job yourself!