Technical Alterator escape route

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Technical Alterator escape route

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Gerrard’s alternator pulley has been squeaking a bit for a while and yesterday it decided to make a bid for freedom. It couldn’t fall off completely because of the chassis rail but it’s half hanging off the alternator so it’s probably time for a new alternator.

What’s the best way to extract the old one? It looks like there is no way to remove it from above so it’ll have to be from below... but is there an official route out? Does the subframe have to be shifted?

I’m going to replace the whole alternator rather than try to repair the pulley.

Ta,

Ralf S.
 
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The alternator will only come out from below.

Replaced the alternator on one of my JTDs about 5 years ago. Pictures I took at the time show that I took the complete right side driveshaft out. I don't remember if that was because I fitted the bigger 120 Amp alternator, or if it was necessary to remove the driveshaft to get the original 90 Amp alternator out.

Be careful not to lose the top bolt spacer. It can fall out when you remove the top bolt. If you don't realise it's fallen out and refit the alternator without the spacer, the top bracket on the engine will break.
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If you remove the left-hand engine mount and lower the engine with a jack, you can pull out the alternator from above. I did it last weekend.
 
Was this on a JTD? I might give that a go at this rate... :)

Meanwhile I’m stuck at remove the driveshaft. How does the offside driveshaft cup come out? Does it just pop out like the nearside one or do I need to loosen or remove parts around the support?

It looks like I can ignore the support and just drift the cup out from behind but it’s not coming out easily so I just want to check there’s not something holding it in place before I whack it harder.. :D

Ralf S.
 
The support looks like a MoFo.. there’s a 15mm bolt at the top and a couple of 17mm nuts at the bottom. The nuts came off quickly enough but the 15mm bolt is very inaccessible with the driveshaft in place and it’s rounded slightly. It’s not going to come out without some new swear words being invented.

Ralf S.
 
hi davren do you have any alternator connector diagrams at all
im pretty sure my alternator is not charging on my jtd 150 16v and i will not be doing on the drive (with this mention of driveshafts etc)so dropping off at a garage mon and would just like to confirm all supplies and connections to and from alternator.
had issue a month ago where belt got cut and suspected alternator but gave it another chance with a new belt, but now belt looks ok but now not charging at all, usually 14.1v and sat at 13v with lights on , 14 v with lights off and a lights on heated rear screen on dropped it straight to 12.8v, so pretty sure it is the alternator its original 12 years old.
many thanks.
 
hi davren do you have any alternator connector diagrams at all

This is the 2004 on, JTD 16v wiring diagram for starting and charging.

Same as the 8v versions except for the alternative wiring shown dotted for the 16v.

A10 = Alternator
A20 = Starter Motor
H1 = Ignition Switch
M1 = Body Compiter

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my stilo is a jtd 140cv. you have to disconnect the return gasoil pipe and unbolt and push out of the way the oil stick.

after supporting the engine, you have to take out 3 15mm bolts and the 3 18mm (I think) nuts.
 
little update , car back , mechanic did say bit of a pig of a job im pretty happy as the whole job inc parts(alternator £129) total £263
booked £90 labour ,about 2.75 hrs as hed stated 35 hr.
not wanted but gotta have it to keep em going.
 
Well.. I managed it in the end... :D and in hindsight it wasn't so tricky.

The biggest problems were the never-been-undone nuts and bolts, and working out the right order to do everything.

The alternator will only come out between the engine and the bulkhead, via where the offside/right driveshaft lives.

To remove the driveshaft you first have to remove the support bracket. It's held in place by some nuts and an engine mount, so the first job was to loosen the mount and jiggle it out of the way. It's an 18mm from memory and very dry/rusted on my old beast so I was afraid I would damage the threads... but half a can of Plusgas and another of WD40... it survived. :)

Next job was to remove the nuts/bolts. The nuts are 17mm nylock and no bother, although on mine one of the studs came out of the block, instead of the nut coming off the stud.

The bolt is a 15mm hex and is very inaccessible. The support is in the way from below... so the only way to get a spanner on it is from above, but then there's very little room to turn it because Fiat put the engine and the bulkhead just where the spanner/ratchet wants to go.

I'd rounded the nut off a bit (unable to get a straight angle of attack on it) so I was preparing to introduce it to Her Majesty (Grinder, queen of the workshop) but just for this job I bought a 6-sided Hex socket which gripped the bolt head better and that broke the stiction.

Driveshaft off needs the gear oil drained. Luckily my old mum had just that day bought a brand new 5ltr plastic bucket, so I used that to catch my oil. It's only 1000 miles old, since I changed the nearside driveshaft so it would've been a pity (£25) to bin it.

Driveshaft just came out when the support bracket was removed.

The alternator was similiarly truculent. There's a 15mm pass-through bolt above and a 17mm pass-through bolt below. The 17mm bolt came undone okay (you can get a spanner onto both the nut and the bolt head) but the top one was way more fiddly. Again, space to get a spanner onto the bolt/nut heads and then turn it is the biggest problem.

The spacer fell out when I removed the bolt. If I hadn't read Davren's post above I might have panicked.. but I still didn't see where it fell out from. I worked out that it fits into the void behind the outer face of the alternator bracket, on the chassis rail side of the assembly.

The alternator is held in contact by 12mm and 8mm bolts (positive and earth) which were easy to undo.. but disconnect the battery first as the connections are "hot" and the beast sparks a bit if you accidentally earth yourself while undoing the nuts. :D

The alternator I used was a Denso DAN501 ... 105A @ 14V and just £105 for my old beast's standard Fiat (but also made by Denso) part 46782213. I noticed that the standard one used a Magneti Marelli regulator/rectifier whereas the Denso was slightly different and unbranded (probably Hitachi?). Marelli had a cover over the electical connectors whereas the Denso/Denso didn't. I doubt it's too serious.

Putting everything back.. I ran out of energy trying to faff about with putting back the alternator top-bolt/spacer/washers/nut with one hand up the back of the engine and the other steadying the alternator... so I removed the flywheel pulley and the aux-belt tensioner to open up a bit of space through the wheel arch. It takes about 5 minutes longer... but it saves the time immediately and no arseing aboot.

Refitting everything else was the opposite of dismantly... just remembering what I'd removed in what order, and tightening all the bolts that were just loosened, including the gear oil drain plug and the bottom engine mount... then re-filling the transmission oil (degreasing mum's bucket so that she couldn't tell the difference) and topping that up to the correct level. Aux Belt is 6PK1270 for me (air-con model).

So far, the beast is running smoooooth. I didn't realise quite what a racket the alternator had been making... so worth all the aggro. I think.. :D
 
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The spacer fell out when I removed the bolt. If I hadn't read Davren's post above I might have panicked.. but I still didn't see where it fell out from. I worked out that it fits into the void behind the outer face of the alternator bracket, on the chassis rail side of the assembly.

One of my pictures in post 2 above shows where the spacer belongs. ;)

I ran out of energy trying to faff about with putting back the alternator top-bolt/spacer/washers/nut with one hand up the back of the engine and the other steadying the alternator

When I did mine, I put a small piece of plastic tube to hold the spacer in place between the 2 aluminium brackets, then pushed the bolt through, which in turn, pushed the plastic tube out.
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