Removing Alternator Pulley

[Timja]

Anyone know the best way to remove the pulley on the alternator? Is a special tool required?

Does anything special need to be done when fixing ot onto a new alternator?

[BeastMaster]

When I changed mine, a pre serp version, I dont remember having any problems fitting it. The only issue I had was making sure that the secondary belt was in perfect allignement. It took a bit of a fiddle to stop it squeeking. Andy

[Timja]

Not sure if i was clear, i have bought a new alternator that doesn't have the pulley wheel attached to it so i need to remove the wheel attached to my old alternator and fit to the new alternator but not sure how to remove...

[EggsBenedict]

impact gun works well. If you don't have one, just take it down to local garage - they'll be able to do it OK...

[Goodwin]

I did the same a few weeks ago, You will need a big allen key/hex bit and a big spanner; and ideally something to hold the alternator still. It comes undone but may need a bit of grunt. Stating the obvious but pay attention to arrangement of washers spacers etc. when you transfer over. Not sure if you are close to me but if so your welcome to drop around, PM me if so. Should take about 5-10 mins.

[Ribol]

Timja said:

............i have bought a new alternator that doesn't have the pulley wheel attached to it so i need to remove the wheel attached to my old alternator and fit to the new alternator but not sure how to remove...

It depends on if the pulley has a keyway or not.

If it has a keyway you hold the pulley in a vice and undo the nut. If it hasn't got a keyway the rotor will probably have a hex hole in the end of it for an allen key, put the pulley in a vice, ring spanner on nut, allen key in place, undo nut.

[Simon says]

Ribol said:

Timja said:

............i have bought a new alternator that doesn't have the pulley wheel attached to it so i need to remove the wheel attached to my old alternator and fit to the new alternator but not sure how to remove...

It depends on if the pulley has a keyway or not.

If it has a keyway you hold the pulley in a vice and undo the nut. If it hasn't got a keyway the rotor will probably have a hex hole in the end of it for an allen key, put the pulley in a vice, ring spanner on nut, allen key in place, undo nut.

What he said ^ takes me back a bit as the only one's I do now are late motors with sprag clutches in them and are more unreliable than using a crisp packet as a condom

[Timja]

Goodwin said:

I did the same a few weeks ago, You will need a big allen key/hex bit and a big spanner; and ideally something to hold the alternator still. It comes undone but may need a bit of grunt. Stating the obvious but pay attention to arrangement of washers spacers etc. when you transfer over. Not sure if you are close to me but if so your welcome to drop around, PM me if so. Should take about 5-10 mins.

I couldn't get any of my spanners to fit mine as the nut is recessed inside the pulley, see photo below (with nut loosened), was yours the same as this?

Thanks for the offer of help, but i'm a bit far away (plus now sorted)

Ribol said:

It depends on if the pulley has a keyway or not.

If it has a keyway you hold the pulley in a vice and undo the nut. If it hasn't got a keyway the rotor will probably have a hex hole in the end of it for an allen key, put the pulley in a vice, ring spanner on nut, allen key in place, undo nut.

What is a keyway? They undid it by the method you said though so has mine got this? Mine has the hex hole in the end so i am a bit confused what tyoe mine is... can't see any way a ring spanner would fit on the nut as it is recessed... If it wasn't recessed then this is how i would have done it, main confusion was over how to hold the nut and use an allen key at the same time...

EggsBenedict said:

impact gun works well. If you don't have one, just take it down to local garage - they'll be able to do it OK...

Decided this was a good idea, so after looking in Halfords to see if there were any spanners that would fit i popped next door to the Halfords Autocentre in Banbury, asked them nicely and 20 secs later they reappeared with the alternator with nut loose. They said they clamp pulley in vice and undo with airgun.

Thanks for all the advice.

This brings me onto the next question.... how tight does it need to be done up? or does it keep fairly tight with the belt going round?

[Goodwin]

It depends on the keyway question. If your pulley has a slot in it and the alternator has a grove machined in that can line up then it doesnt need to be too tight as the key way provides the drive. It does however sound as though you do not have the key way (hex in the shaft and a nut) at which point the only thing providing drive between the pulley and the alternator shaft is friction on the mounting flange. Therefore much tighter (but dont be a total gorilla). If you have the right sized spanner then about 3 white knuckles tight (yes a really precise engineering measurement). Incidently an open faced spanner will work much better as you will be able to hold at a slight angle to get into the pulley dish and it will be harder to totally overtorque the nut. Ring spanners are not always the best.

[Ribol]

Timja said:

Ribol said:

It depends on if the pulley has a keyway or not.

If it has a keyway you hold the pulley in a vice and undo the nut. If it hasn't got a keyway the rotor will probably have a hex hole in the end of it for an allen key, put the pulley in a vice, ring spanner on nut, allen key in place, undo nut.

What is a keyway? They undid it by the method you said though so has mine got this? Mine has the hex hole in the end so i am a bit confused what tyoe mine is... can't see any way a ring spanner would fit on the nut as it is recessed... If it wasn't recessed then this is how i would have done it, main confusion was over how to hold the nut and use an allen key at the same time...This brings me onto the next question.... how tight does it need to be done up? or does it keep fairly tight with the belt going round?

Since yours has the hex hole it won't have a keyway. The pulley is stopped from slipping by clamping it between the nut and the spacer which rotates with the rotor and stops the pulley from touching the front of the alternator.

The ring spanner you use is one with a cranked end that is narrow enough to go down the recess.

[Timja]

Ok, thanks. I understand now. Couldn't get my open spanners to fit in the 'dish' and not got a cranked ring spanner that big and looks like it will cost about £20 to buy one so i might just take to a garage and see if they can tighten it for me. Looks like it is 24mm nut if anyone else looking to do this in the future.

Thanks again!

[Ro55G]

Hi I am new to owning a Cerb striaght 6..noticed pas belt was badly frayed anyway in trying to remove the shoulder which holds the aux drive shaft I sheared a hex head so need to remove alternator drive puley wheel..in trying to do so with pullers was really tight ..does it just pull off?? Thank you very much for your help..forums have been really helpful!

[Ro55G]

Edited by Ro55G on Saturday 30th January 08:15

[FoxTVR430]

I think you will get a better answer in the Cerb forum, not the Chimaera one. 😁😉


P.S. It looks like it should just pull off, Good luck

[Austin Seven]

If there's room to get one in, a slide hammer with puller legs attached would probably get it started. A squirt of penetrating oil the day before would help too.

[Paulprior]

Yours has the keyway that has been discussed above, the key is just a rectangular piece of steel that fits half in shaft and half in the pulley, at about 5 o’clock position in your photo, so a good shirt of penetrating oil and ideal a bearing puller to pull it off, if you can’t get one in maybe you can gently try prying it off from the back, but just a little at a time and keep rotating it

[Ro55G]

Thanks all for you help heat, oil and a pulley puller did the job.
Cheers

[Ro55G]

Thanks Paul finally got the seized bolt of from the saddle which holds the aux drive shaft..I thought that saddle would just slide off? It seems to just be pulling the shaft when I try to remove it..thanks for your help