How to change the alternator?

[Marian]

As per my "Pray for me" thread it looks likely that my alternator is giving up the ghost.

Can anyone give me or point me in the direction of a step by step guide to replacing this on a 96 4.2?

Many thanks.

[tvrgit]

The bit I don't understand is how to remove the fuel rail to get to it! I've just been out and looked at mine and it looks like it's held on with 4 allen screws - if you take those out does it just lift off? Do the injectors come with it or do they stay in the engine?

[Tanguero]

You want to take the fuel rail, injectors and intake manifolds off in one piece.

Run engine with fuel pump relay removed to depressurise the fuel rail.
Remove air boxes
Disconnect throttle cable
Unplug injectors
Unplug throttle pots (leave attached to the manifolds!)
Disconnect fuel feeds to the rail - these will still leak so be prepared to plug the lines.
Undo the hex cap bolts through the manifold to the rocker covers - beware there are spacers under these that you need to make sure don't get lost!!
Undo the hex cap bolts the hold the manifold and heat barrier to the cylinder heads.
You should now be able to lift the whole assembly of fuel rail and both manifolds off in one piece.
Be carefull to keep the 'O' rings that sit between the heat barrier and the block and the barrier and the manifold.

Reassembly is the reverse...

[Toadusmodus]

tvrgit said:

The bit I don't understand is how to remove the fuel rail to get to it! I've just been out and looked at mine and it looks like it's held on with 4 allen screws - if you take those out does it just lift off? Do the injectors come with it or do they stay in the engine?

Or if you are lucky and have an extra light weight Cerb (i.e. no A/C) you can change it without removing the fuel rail. Is a bit of a squeeze though!

[Marian]

Thanks guys, but I'm afraid that sounds way way above my capabilities

As my starter motor is very temperamental (screeching and the kill switch has no affect on it) I guess it would be wise to get that changed at the same time?

[Tanguero]

Honestly it isnt that difficult - its only an hour or so job.

[Marian]

Tanguero said:

Honestly it isnt that difficult - its only an hour or so job.

The fuel aspect of it is what scares me to be honest.

I've ordered a starter motor and it shall be here tomorrow, but I can't find a part number for the alternator, is it the 100 amp one that comes off a 3.9 V8 Land Rover?

[JensenA]

Tanguero said:

Honestly it isnt that difficult - its only an hour or so job.

True - It's quite straightforward, it's one of those jobs that only appear difficult because you haven't done it before - surprise yourself and do it

[Marian]

Is it really a job that can be done on the driveway though? Oh and what tools shall I require?

[JensenA]

Yes it is. No specialist tools required - socket set, hex head sockets or Allen keys.

[JensenA]

....and it will make it a bit easier to fot the starter, and check the big fuse

http://www.pistonheads.com/gassing/topic.asp?h=14&...

[Marian]

JensenA said:

....and it will make it a bit easier to fot the starter, and check the big fuse

http://www.pistonheads.com/gassing/topic.asp?h=14&...

Read that thread this morning

Still don't know a part number for the alternator though

Going to try to get it sorted for Sunday

[mike.williams]

Marian said:

Is it really a job that can be done on the driveway though? Oh and what tools shall I require?

Personally, if you are unsure as to what tooling you require, I would bow out and get someone to do it for you
There's no point in starting a job when there is a possibility that it won't get finished. I've not got a Cerbera, so can't comment on the exact job in hand... but.... knowing when to call in the experts is a sensible place to be.. The sound of "look out for the spacers/O rings etc" strikes me of things that can go wrong.... For myself, that's cambelt time (not on the Wedge I know...) I've watched and helped a mate do mine a few times now, but still haven't fancied doing it myself.
On another note, do you know if the alternator has an external diode pack? It is possible that that is all you need..... (I had to change mine after a battery charger went into overdrive...)

It would be worth your while paying someone for an hour or two surely, or tempting someone with a curry and a few beers......

Good luck, Mike

[tvrgit]

Tom

I don't mind helping you with this, if you like. I would only say that I haven't done this particular job on this particular engine before, either!

And as I said, I have a brand new alternator, we can try it, if it fixes the problem we can sort somethng out, if not, we can swap yours back.

Only problem is I can't really do it before Saturday - I have work lined up tomorrow and Friday.

[Marian]

tvrgit said:

Tom

I don't mind helping you with this, if you like. I would only say that I haven't done this particular job on this particular engine before, either!

And as I said, I have a brand new alternator, we can try it, if it fixes the problem we can sort somethng out, if not, we can swap yours back.

Only problem is I can't really do it before Saturday - I have work lined up tomorrow and Friday.

Andrew that would be great Obviously I can either buy the alternator from you or get a replacement for you

Whatever day is suitable for you will be suitable for me.

[mike.williams]

tvrgit said:

Tom

I don't mind helping you with this, if you like.

Was it the curry or the beer?

But my question is still sound... does the alternator have an external diode pack? I am assuming that it is not the bearings that have gone....

[tvrgit]

mike.williams said:

But my question is still sound... does the alternator have an external diode pack? I am assuming that it is not the bearings that have gone....

You're right - it might be easier to check for an external diode pack, as I think that may be where I think the problem lies - I mentioned that in Tom's other thread about the original problem! Don't know if you can still buy those separately.

[Marian]

All this talk of external diode packs is alien to me I'm afraid as I have no idea what it is or what it would look like or else I'd go check

[mike.williams]

Marian said:

All this talk of external diode packs is alien to me I'm afraid as I have no idea what it is or what it would look like or else I'd go check

Well here's a photo of mine... but it probably won't be the same a the Cerberas..



see the red outline? it's just held on by 4 small bolts, undo these and off comes the diode pack and the brushes (on springs to self adjust....)

ATB, Mike

[Adrenochrome]

Well Andrew (tvrgit) has very kindly offered to come over this morning so we are going to have a go at changing the Alternator and Starter Motor, I shall update with pics for anyone doing this in the future.