Alternator pulley, Removable ?

Technical Area Engine, Transmission, Exhaust etc
2

My alternator pulley is rough. Rusty, with deep pitting.

Now on my second drive belt in two years.

 

 

So can it be removed? Are new replacements available?

 

I have a lathe so if it comes off then I could clean it up, but that would depend on removability / replacement.

 

I believe a new alternator is £150 ish ; but then if this happened on a track/AutoSolo day it would be day spoilt.

 

Paul G

3

Hi Paul

Is it the LR180 Hitachi as originally fitted?

In any event not found an alternator yet where the front pulley can’t be removed.

I used my Hitachi impact 6905B wrench and a 24mm impact socket to remove ones on the LR180. Just grip it with your hand and the driver should release the top nut and the pulley just comes off. 

If the inner surfaces on which the belt runs are good and no damage to belt contact surfaces  I would not worry too much.

These come to me in all sorts of condition and it is only ever the cosmetic part that causes concern. As I sell these spend time chipping off the rust from the front of the pulley and hydrate 80ing.

Let me know if you want a cleaned up treated pulley - have several in stock.   

4

Thanks for the reply Rhino.

It’s a 4 grove pulley and its the groves that are rough & pitted.

I have a (Lidl) impact wrench that rips wheel nuts off no problem so I’ll give it a go on Monday.

I’m a marshal tomorrow at the Corbeau Seats Rally, Tendring & Clacton, so MiXi will have to wait, although her MOT is Wednesday so need her fixed by then.

 

Cheers,

Paul G

 

5

A shame the corrosion has effected the crucial belt contact area. In that case would recommend replacement.

Edit - item below is out of stock.

Check you can remove the old one first but here is a brand new item at a fair price.

You are looking at a 4 belt pulley for a Hitachi LR180-766 or LR170-758 - they are the same pulley.    

6

 

 

Thanks for the link. Unfortunately out of stock but I have asked for notification when available.

In the meantime I cleaned the old one in situ as best as I could with a file and rotary wire brush.

If a new one turns up I’ll fit it together with another belt. At least I"m ready for the MOT at 8.30am this morning.

 

Paul G

 

 

7

Hi Paul

I have a few of these spare - see attached photos below.

If it suits, take your pic - £5 fee free posted.

Whilst you have the alternator off the car, take a good look at the aluminium casings particularly where the four mounting bolts pass through.

These original alternators are all getting to the end of their useful life, hence my spares. Once the aluminium cracks the armature will start to

move off centre with the field coils and the eventually start to seize and take the belt out.        

8

I have a slightly different alternator problem, but I hope you dont mind if i jump on this thread.

Investigating a squealing belt i’ve had the belts off to inspect the pulleys. they all seem fine, the power steering seems to get a little more resistant as i turn it but i assume that’s just the pump acting.

Anyway, once i loosen the alternator adjustment bolts at the top there is a fair bit of play in the bottom front mounting, play in whatever the bolt goes through, from side to side. It seems to be secure once everything is tight but not sure what has happened here, there are no cracked casing and the bolt runs right through. Is it ususal not to have a nut on the front, i assume in threads into the casing.

I havent been under to have a look from down there. Have you seen this before?

 

Thanks

 

9

Hi Tim

Squealing belt is usually one of two things - belt too loose or partial seizure somewhere - alternator, aircon, waterpump, etc.

All the MK2.MK2.5 bolt into the front of the alternator casing - poor idea if you ask me as these tend to seize and cause problems for removal - been there and had to cut the alternator casing to remove. Luckily the part was scrap anyway. The MK1 1.6 bolts through from the front to a nut at the back - a much better idea. Easy to convert to MK1 1.6 style by using the MK1 1.6 nut and bolt and drill out the alternator casing thread with a 10mm bit.

If there is excessive lateral play in the pivot bolt area, likely to be wear to the aluminium section on the engine through which the bolt passes. This is not common but I have heard of it before. Probably caused by a loose pivot bolt and continual engine movement in use promoting wear. You have some choices if you are not happy with the way the pivot bolt tightens up. Go MK1 1.6 style with the standard 10mm bolt and see if that improves the situation or you could possible go MK1 1.6 style but drill out and sleeve or drill out and use a 12mm bolt and associated nut.

Hopefully you will be able to get the pivot tightened up, correctly aligned without resorting to the suggestions above as once properly tight there should be no movement.