Date: 18/02/02
This guide is a fairly simple one on updating the old alternator. Originally I tried to get a bigger alternator for the car but was given a maximum sized one of 55 Amps as “that is the only one that will fit the car”. BS I thought but took it anyway. Long story short, with the amount of electronics I am now running I wanted a larger alternator, I decided to go for any early commodore alternator as long as it was larger and found this “reconditioned” 70 Amp alternator on eBay from a VK commodore, when I got it though it was an 85 Amp alternator, all the better.
Date: 18/02/02
The back of the alternator was a little different to the 55 Amp alternator I already had, it had a few more terminals, terminals differently marked (to my eyes) or with different fittings etc I was a bit concerned that it may be useless to me but I remembered that some blokes had put a heap of information up on oldholden recently and so decided to check the holdenpedia. This page: http://www.oldholden.com/possible/index.php/Alternator was a life saver so a big thanks to T, merc9112006 and Qute.
Date: 18/02/02
First on the agenda as with any electrical work on the car is to disable the power by removing the battery terminal wiring.
Date: 18/02/02
Next we remove the wiring running to the alternator, you should have one coming directly from the battery positive that can be pulled of first.
Date: 18/02/02
One more wire runs from the alternator to the starter motor which can be removed, it may be bolted on with a nut.
Date: 18/02/02
Now with the wiring removed from the back of the alternator we can start with the actual removal of the unit. Firstly we need to get the fan belt off the alternator, this can be done by loosening the bolt at the top of the alternator which is attached to the bracket which goes back to the motor. Once that bracket is loosened you can lever the alternator towards the motor which will lower the tension on the fan belt and allow you to remove it.
Date: 18/02/02
If the alternator won’t move (and even if it does you need to do this step next anyway) you will need to loosen (and remove to allow removal of the alternator) the bolt that supports it at the base. If you get under your car and look up at the alternator it will look like the image shown.
Date: 18/02/02
Apologies for the bad image, the flash decided to not work…you will need two spanners, one to hold the bolt and the other to loosen the nut.
Date: 18/02/02
When the nut is near the end of the thread give it a tap to free the bolt up, then you should be able to remove the bolt and nut. If you tap the bolt back like shown before removing the nut completely you should be able to then pull it out by hand when you are ready to remove it.
Date: 18/02/02
Not that it is easy to see on this car but here I am levering the alternator back towards the motor to remove the fan belt. Note that I have loosened both the upper bracket bolt and the lower bolt so the alternator moves very easily and I don’t need to force it.
Date: 18/02/02
Depending on your set up you may need to drop the alternator downwards to get it out or may be able to lift it out through the top, this bracket on the side of the motor that supports the alternator will need to be removed if you want to try to drop it out through the bottom of the bay.
Date: 18/02/02
If you are coming out through the top you may need to remove the bracket that supports (and supplies tension to the fan belt) the alternator at the top. This bracket will be supported at the motor by one bolt near the water pump.
Date: 18/02/02
This is the upper bracket removed. The one shown is actually two bolted together as my fan belt is too long so I needed to push the alternator further out (yes, yes, one day I will finally get around to buying a new fan belt…)
Date: 18/02/02
If you are bringing the alternator out through the top of the bay you will need to take your battery out to get some more free space to work. Start with removing the earth leads from the negative terminal.
Date: 18/02/02
Next the battery is held by a bracket over the top of it, you can remove it by loosening the two nuts supporting it and then lifting the bracket off the bars.
Date: 18/02/02
Now the battery should be right to be removed from the car, don’t put it down on cement if it is going to sit for a while but rather up on some blocks of wood. For reasons I’ve never pretended to understand sitting a battery directly on cement will discharge it fairly rapidly (say over a few days if fully charged).
Date: 18/02/02
With the battery removed you should be able to jiggle the alternator out through the top, if I can do it on this car with all those wires than anyone can!
Date: 18/02/02
A comparison of the two alternators (new on the left) from the rear, as you can see here the wiring will be done slightly differently, but if you read through the holdenpedia page mentioned earlier it is still a relatively simple job to get this new alternator working properly.
Date: 18/02/02
To keep the wiring running on the same angles to the new alternator I need to unbolt the housing and turn it 90 degrees to match the old one, yes I’m being picky but what the hell. Firstly we remove the regulator which is held by two screws at either side.
Date: 18/02/02
This is an image of the regulator removed, you can see the terminal type required. The old alternator used one wire here where the commodore has the same one plus another to a dash light, if you wire the two as shown later then it will work fine.
Date: 18/02/02
At the front of the alternator are the four long screws that run right along the edges of the alternator and hold the housing, if you turn the pulley at the front by hand you should be able to get to all 4 easily and remove them.
Date: 18/02/02
Here is an image of one of the screws being removed, as you can see they are quite long.
Date: 18/02/02
Here all the screws are removed and the housing is ready to be turned to match the old alternator.
Date: 18/02/02
And here the housing has been turned to match the old alternator, with the regulator and four screws removed this is a simple turn by hand operation.
Date: 18/02/02
Now we can put the four housing support screws back in and reattach the regulator. It appears in the image that the regulator will conflict with the lower bolt but this isn’t the case, in fact there is a bit of free space there.
Date: 18/02/02
I didn’t have any terminals that would fit the one matching the commodores alternator regulator (if you get an alternator from the wreckers it might be worth cutting that wire and taking it too). So what I’ve done is attached two terminals to the old terminals allowing me to use a push on fitting to each.
Date: 18/02/02
I’ve then made up a small wire which will go from one of the regulator terminals (S) back to the alternator housing where the battery terminal will connect to, this information came from Merc9112006.
Date: 18/02/02
Once the alternator is back in the car you can then reattach the battery to alternator wire as shown, you can see the wire that runs back to the regulator here too.
Date: 18/02/02
I’ve actually reattached all the wires here so that you can see how they will be connected, the thick red wire goes back to the battery, the black wire goes to the starter and the small red wire is the connector from the regulator to the alternator battery connection.
Date: 18/02/02
Now with the alternator back in the car I have spread the two terminals on the alternator regulator so that they have no chance of contact. Then put the lower bolt back into the alternator to support its weight while I work at the top.
Date: 18/02/02
With the bottom secured we next need to attach the fan belt to the pulley at the front of the alternator and then lever the alternator out away from the engine before tightening the bolt at the top which will hold it to the bracket. Generally it’s tight enough when the fan belt will press in about a fingers width.
Date: 18/02/02
And here it is job done, you can’t notice this is a bigger alternator by just looking at it so I’d recommend this upgrade to people who even want there car to appear completely original. I’ve had this alternator in for a few months now and except for one occasion where a lower wire fell off due to the vibrations from driving on a local panel beaters rocky driveway (well it is a chook farm too I guess…) it has been perfect and done a great job.
