Changing Alternator on AJP 4.2

[Warwick67]

Hi, I'm just branching out from the TVR club forum....

Alternator packed up on my Cerb (AJP 4.2) last night on the M20 coming back from Le Mans. My mate I was travelling with - get this - towed me with his Chimaera (!) to Maidstone services, where I waited nearly 5 hours to be recovered...

Anyhow, question is - how tricky is it to change the Alternator, I'm reasonably good with a spanner but new to Cerbs and it looks like TVR tried to hide the alternator under a load of gubbins (technical term) - any advice much appreciated.

Cheers
Warwick

PS: great race

[SimonSparrow]

Hi,

Not done it myself, but the fuel rails etc. come off easily enough and then you should be able to access it. Be worth checking the 'big fuse' near the starter motor as that can fracture and give the same symptoms but only costs £1 and some skinned knuckles to fix.

[APB_V8]

Hi

The alternator is not to bad, just getting the injectors out with the fuel rail can feel like you are going to snap them in half, but they do come out:

1) Remove the fuel pump fuse and start the engine. The engine will die after about a second. This depressurises the fuel in the rail.

2) Undo the four hex bolts in each corner of the fuel rail and 'wiggle' the injectors out with the rail (leaving the injectors in the rail rather than the heads stops the remaining fuel leaking out of the rail and into the V)

Stuff toilet paper into the inlet holes so not to drop anything down them!!!!!

Be careful not to drop anything into the V, swine to recover anything that rolls under the alternator/coil pack brackets.



3) IIRC the alternator is off a Range Rover classic (you need to check that) and is held on (looking from the front of the engine) a long pivot bolt at the bottom right and a shorter bolt on the left which is for belt adjustment. Undo both and remove belt (I found the belt was a swine to get off the engine pulley due to space. I would leave it on unless you are changing it, just remove from the alternator)

4) Remove wires from rear (remember which they connect to) and remove long and short bolts.

5) Refit is the reverse of above. Place one set of injectors in one bank, but not so far as to allow the o-ring into the head. Then place the otherside injectors by the inlet holes in the head and push the injectors to a-line with the holes so the injectors slip in. It will go back in!! Be careful not to damage the o-rings.

Hope that helps.

PS

As mention, you may want to check your 100amp fuse first. Follow the large (red in my case) lead from the alternator to the 100amp fuse which should be in a black plastic box on a plate held in place by the two bolts on the rear of your coil packs (closest to the bulkhead) which are in the V next to the alternator. From the photo below you can see in mine, when I was rebuilding her, that you can see the orginal Aluminium strip/100 amp fuse looked OK but it had a piece of multicore by passing it. I have since replaced it with a 125 amp.

Edited by APB_V8 on Monday 13th June 16:12

Edited by APB_V8 on Monday 13th June 16:13

[Gazzab]

I presume you have checked the big fuse?

[jon h]

Do you have air con? If not, the alternator can be removed through the front of the vee without touching the fuel rail. (If you do, the compresor will be in the way) I did this recently- it is a tight fit and you have to twist and turn it a bit, but it was fairly painless, overall. Definately check the big fuse first though.

[Warwick67]

Cheers APV_V8,

I'll go check the big fuse before I do anything else.

I was just looking at it wondering if it might be easier to move the air con pump out of the way and slide it out fwds? Guess not, seems straight fwd enough.

Thanks
Warwick

[APB_V8]

No problem.

If you do take the rail off, might be worth taking a look at your coil packs. It gets hot down in the V and the plastic comes away from the resin centre and lets water into the coils. The cheap ones are only £27 each from GFS (N92512) and easy to replace if the press fitting do not spin on the bracket (just drill off the head of the bolt and pop to B&Q and get some replacement bolts)



Andrew

[Tanguero]

On a 4.2 do not take the fuel rail off the throttle bodies. It is far easier to remove the throttle bodies with the fuel rail attached. It gives you much more room to get to the alternator and means that you dont even have to touch the throttle link rod or readjust the pots.

Just unclip the throttle cable, remove the fuel hose from the rail, undo the bolts that hold the rail to the cam covers (being carefull to grab the spacers from under the rail), undo the cap head bolts that hold the bottom of the throttle bodies/heat barrier to the block and lift the whole thing away as a unit. The only point to watch is the spacers - if you drop one of those into an open inlet you will be in a world of pain - but apart from that it is a quick and easy job.

You will then have decent access to the alternator and coils.

When you are reassembling it all - use a little dab of Hylomar blue or similar to hold the 'O' rings to the throttle heat barrier.

[350Matt]

I fouind its even easier than that as you can leave the inlets in place and just remove the centre portion / fuel rail

as if you do remove the inlets for gods sake don't drop the ally spacers down the inlet as I did

when I eventually got it out again after a day of fishing with bits of wire, using a hoover, blasting an airline etc etc and yes I did the little happy dance when it finally fished it out again as I has visions of turning the car upside down and rattling it.....

[Tanguero]

Personally having had the top end apart a number of time and tried both ways, I find taking the throttle bodies off gives far better access and is far easier to put back together. Though as said you do need to be aware of the spacers before you lift the assembly away.

[Warwick67]

Quick note to say thanks for the advise, Cerbie is back in business with a shiny new alternator.

I learnt a few things along the way:
1) you can get the alternator off quite easily by undoing the A/C pump and moving it out of the way, the alternator fits through the space
2) if you drop a nut down the V of the engine its a right bd to get it back again
3) rather than arse about for a couple of hours failing to get the pulley off the old alternator to switch it onto the new one, take it down to your local friendly garage who, with a air impact driver, will get it off in about 10secs, in exchange for a pint...
4) if your not sure whether youre gonna have power when you come back to the car, leave the bonnet unlocked;) sooo much easier

Ohhh the noise

[APB_V8]

Glad it's all sorted.

Have to remember the A/C pump trick, a lot safer than fuel going everywhere

And parts in the V are a swine to get at

Andrew