Replacement of Alternator - Oil Seal 4.5 AJP

[schimg]

Well after much work during the winter months and some more in the spring got the cerb MOT'd and did 700 mile trip to Cornwall (with five other cerbs + even more TVR;s)

All went well apart from during the return journey I noticed some oil spots on the inside of the bonnet above the alternator area..and on the front of the F1 panel..further investigations revealed an oil soaked centre chassis rail on the passenger side of the car and oil levels dropping down to just above low level (phew!) ...

So it would appear to be the alternator oil seal has died...I have checked the centre of the Vee...there appears to be plenty of oil there...so sort of confirms the seal prob...

What are peoples thoughts?

I have already whipped off the induction stuff ...I guess the fuel rail is next?

Then the throttle bodies?

How do I do this?

Any tips thoughts would be appreciated..

thanks in advance

Steve.G.

[tvrgit]

I assume you mean the seal in the layshaft that drives the alternator? The alternator itself doesn't hold any oil to speak of!

The layshaft is driven off the timing chain - I don't think you can remove the shaft or change the oil seal, without removing the timing chain - and I haven't done that, so I can't advise, sorry.

Are you sure that's where the oil is coming from? it could be leaking elsewhere, and running onlt the shaft and then getting sprayed everywhere?

If you want to get the alternator off, then you're right - to get to it, you have to take the fuel rail off. First depressurise the system by taking out the fuel pump relay, and trying to start the car for a few seconds. Then disconnect the positive terminal of the battery.

Then take off the throttle cable and the linkage across the back of the engine between the two spindles. Do this in a way that doesn't affect the adjustment - removing the whole bracket is probably best.

Then there are two hoses on the back of the fuel rail - one is the fuel feed, the other is a vacuum hose - take them off. Then undo the 4 cap screws holding the fuel rail onto the inlet manfolds, and you can lift the rail to the front of the engine without disconnecting it completely.

The manifolds are held on with 4 bolts into the head, and 2 which go into the top of the rocker cover. These latter ones have small spacers underneath - don't lose them and don't let them fall inside the engine!

Then the alternator comes out in the normal way - remove the two cables, remove the adjuster bolt and the long pivot bolt underneath, and lift it out.

[schimg]

Thanks for the reply.. yes I mean the seal for the alterantor drive...are you telling me I can't do this with removing the cam chain then?

Been told that the throttle bodies need to be removed too...in order to get at the alternator...how do they come off?

I need to test the alternator too as there appears to be a drain on the battery following connection of a black cable to the earth side of the battery when it should have been a red coloured cable ...and connected to the positive!

I have already removed the battery which has charged and held a constant charge...been told that the power surge could have killed a diode in the alternator which means that there is a constant drain when everything is turned off?

The alternator runs well otherwise as I just did a 700 mile trip to Cornwall and back..

Been told that the oil leak could be from the oil pressure switch at the bulk head side of the "V" eitherway need to get it stripped to fix asap as I want to drive the car!

thanks for your reply...got anymore thoughts?

[tvrgit]

schimg said:

Thanks for the reply.. yes I mean the seal for the alterantor drive...are you telling me I can't do this with removing the cam chain then?

Haven't done that, but that shaft is driven by the timing chain from the front, so I can't see how you could take it off without taking the timing chain off.

schimg said:

Been told that the throttle bodies need to be removed too...in order to get at the alternator...how do they come off?

Not sure of the detail for the 4.5 - mine is a 4.2 and the inlet system is different. They will be bolted into the heads, underneath the rubber induction tubes.

schimg said:

I need to test the alternator too as there appears to be a drain on the battery following connection of a black cable to the earth side of the battery when it should have been a red coloured cable ...and connected to the positive!

I have already removed the battery which has charged and held a constant charge...been told that the power surge could have killed a diode in the alternator which means that there is a constant drain when everything is turned off?

Highly possible. You should be able to get an auto-electrician to check it and change the diode pack if necessary.

[schimg]

Thanks for replying again...

Looks like I need tio remove the alternator so will be tackling the job tonight...spoke with a mate with a 420 earlier he can't see the need to remove the throttle bodies -butterflies either...I will whip the drivers side induction off (again!) and the fuel rail....as the battery and half the induction is off the car I will keep loads of absorbant cloth around and a fire extinguisher for any fuel that may still be under pressure...not been run for at least two weeks tho ..poss drop in pressure.

I will get the alternator checked out - refurbed and clean up rectify any drama's I find on the way...thanks again...

Be good to actually get to drive the thing for a bit...

[itiejim]

Changing the oil pressure switch is easy enough once you've got the alternator and TB's out of the way. Even if it's not leaking, having removed everything, it's probably worth changing anyway given what it costs.

To change the auxiliary shaft seal (under the alternator) will be fun... You'll have to remove the drive pulley for the alternator (just one big nut) and then pull the pulley off - there's a key in the shaft if I remember correctly. After that, you might be able to pull the seal out with some sort of a hook, bent screwdriver etc. Basically, you are trying to pierce the seal between the shaft and the block and then pull it out. In honesty, I don't know how easy that's going to be. Failing that you MIGHT be able to just push another seal over the top and press it in, thereby pushing the original seal further down the shaft. It's a bit of a bodge, but the only other option is to take the timing chain cover off which means removing the engine.

If you can't get the original seal out, I'd try speaking to one of the better known engine specialists to see if they can give you some advice.

[optimax sniffer]

Hello Steve,

When I did my alternator a few years ago, I took the induction, the fuel rail & injectors off. I also had to take the aircon compressor off, didn't need to disconnect the pipes as there was enough give to move the compressor out of the way.
Once I got to the alternator I had to release that from the mounting plate, then the mounting plate from the block, then had to re-arrange the parts to enable the extraction of the alternator by bringing it forward and out of the gap previously occupied by the compressor.

When I had the injectors off I replaced the o-rings.

Edited by optimax sniffer on Tuesday 27th July 15:34

[schimg]

optimax sniffer said:

Hello Steve,

When I did my alternator a few years ago, I took the induction, the fuel rail & injectors off. I also had to take the aircon compressor off, didn't need to disconnect the pipes as there was enough give to move the compressor out of the way.
Once I got to the alternator I had to release that from the mounting plate, then the mounting plate from the block, then had to re-arrange the parts to enable the extraction of the alternator by bringing it forward and out of the gap previously occupied by the compressor.

When I had the injectors off I replaced the o-rings.

Edited by optimax sniffer on Tuesday 27th July 15:34

Cheers Iain,

this is exactly what we did, the mounting plate was a bit of a struggle but got it out of the way...the drive wheel clearence off the input shaft was very tight (4.5 problem?)

Got the drive belt and wheel off the alternator...the input shaft is defo not leaking...nither is the oil pressure switch...now it is either oil there from before when I had the cam covers off or new oil since then...thing is there is no trace of a run line!

The throttle bodies are still in situ ...no need to remove them as the alternator came out of the front of the "Vee" ...will get the coil packs off tonight...then the housing plate..the coil packs look well manky ...one of them at least has cracks in it...

Getting the alterantor and battery checked on the way home tonight...

Looks like I need to now buy two coils packs - alternator drive belt which is split - oil pressure valve / switch - poss new leads (if I can get them in purple -don't ask!) -will replace the hose that runs underneath the fuel rail with braided whilst I am at it...plus clean it all up..

Will post some pictures up for a bit of interest..

Thanks for all of the input..

I still need to find the source of the oil leak that is on the pasenger side of the engine...knwo there are some oil pipes there so good place to start...was hoping that it was just the seal that had gone and was peeing oil out...not the case...keep looking I guess!

Edited by schimg on Wednesday 28th July 13:29

Edited by schimg on Wednesday 28th July 22:04

[Sagtvrland]

Just changed my Aux shaft oil seal. Stripped it down to sort oil switch and starter heat shield out.

Pretty easy once you have everything out of the Vee....... Found oil in the bottom of the Vee and old leaves / sludge.

I made a small puller out of some screws and pliers, to pull the seal out, came out pretty easy.

Sorting everything out whilst its apart, painting etc.... don't want to do this again.

J

[Chimp871]

Interesting. Once you had the old seal out, was it easy to press in a new one?

If so you may discovered a big time saving solution.

[Byker28i]

Was it that seal? I had oil in the V after a service where they'd touched the rocker cover whilst putting it on, so the sealant wasn't complete.
It sure made a mess of my engine bay by the time the belt had thrown the oil all around.