When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
115 Amp? That's giving around 2 horsepower in old money! The fans night hit that running at maximum, but that's only a brief peak demand. Most of the time, it must be much less. And the battery is there to deal with intermittent peaks. I would be inclined to see how things go with the 75 Amp alternator. If you see the battery is suffering, upgrade; otherwise stick with the 75 Amp.
I can assure you that with electric fans, whatever the theoretical position might be, you need the 115 amp alternator!
I can assure you that with electric fans, whatever the theoretical position might be, you need the 115 amp alternator!
So far, mine have been OK, but the rest of the system is in very good order and the car hasn't yet seen any summertime traffic jams since the last restoration. I'll see how it goes and let you all know. I have a spare alternator somewhere in my pile of parts ....
Just tell him to fit the pulley from the old alternator, or ask the supplier to send one with the new alt. Then you just shim it up to be in line with the crank pulley using large washers. Your mechanic will have to drill out the bracket holes on which the alternator swings as the old one has an 8mm diameter long bolt but the new alt has 10mm diameter holes. He will also need a new 10mm long bolt.
Sorry that I sent you somewhere without a result. Since that company has (or lists) the original low amps generator, it might be worth asking them if they have a 115 Amp alternator for a later model V12, a Land Rover or other make that would fit the same brackets and has (or could be fitted with) the appropriate pulley. I have a vague memory of people using Land Rover alternators.
Oh, please! Don't apologise! In fact thank you, it's not your fault if they are sold out.
Originally Posted by Peter3442
Since that company has (or lists) the original low amps generator, it might be worth asking them if they have a 115 Amp alternator for a later model V12, a Land Rover or other make that would fit the same brackets and has (or could be fitted with) the appropriate pulley. I have a vague memory of people using Land Rover alternators.
I already emailed them and Tom replied very quickly.
Basically, Tom remembers that the 75A unit was a left handed bracket whereas the 90/115A units were right handed brackets. If so, the only way of getting more power (without spending a lot) would be to make an LRB00284 (120 amp) fit. He suggested that I should be able to buy these quite easily, but it would take some work to make fit.
Any comments? Advice?
I'm unsure if my mechanic is up to manufacturering brackets.
You can buy the 115A units on Ebay, I see used ones from the XJS/XJ40. They will probably need a rebuild, but that should be easy in Europe to find a competent Bosch rebuilder. The 115A units were introduced on the XJS in 1988.
Greg(s) and Peter, sorry, I am getting confused...
The only thing that I am not confused about is that, for this high efficiency cooling system (2 electric Spal fans + fridge in the back) my 75AMP might suffer.
And, apologies, I am starting to get really confused now. Are any of the 3 above a simple drop in replacement for part DAC5224 (as gathered from the Jaguar/Land-Rover parts catalogues)? Is part LRB00284 (recommended by Starter motor and Alternator company) not good? They can procure LRB00284.
I attach images to help you determine which are better for my Double Six
75 AMP alternator Alternator position on left of image Alternator position
Thomas,
ANY of the alternators I listed will be fine. They are all basically the same.
As to fitting it:
see this photo as marked up
The blue box shows the long bolt going through the bracket attached to the engine that provides the fulcrum for the alternator, allowing it to swing in and out as the belt tension is adjusted.
Depending upon the date of your engine, the holes in the bracket attached to the engine, through which this long bolt goes, MAY be 8mm in diameter, as will be the bolt.
The new alternator, which is essential in my view, will have 10mm diameter holes for the fulcrum bolt. All your guy has to do is unbolt the bracket (four large bolts, no problem at all with the alternator removed) and drill out the fullcrum holes. Dead simple; he will have no trouble doing it.
I have just been to the Turin motor museum; FANTASTIC. I am quite sure having seen such wonders as your countrymen created in the 1920s, that ANY italian would have no trouble fitting this alternator!
Last edited by Greg in France; May 3, 2024 at 09:25 AM.
Your advice makes sense and is very good news. I am sure that drilling out the holes will be very doable. Would I need a new pulley or would it be sufficient to adjust the body on the bracket?
I also received the same news from Tom of The starter motor and alternator company who is convinced that my alternator is already the 90/115A and, if I can find an LRB00350 - which I found - then it should fit right in without modifications.
After all, there are only two dimensions to match: the diameter of the holes on the lugs and their distance apart. The first is easily adjusted. The second is almost certainly the same. If there's a small difference it can be worked around.
Unfortunately LRB00350 is no longer available anywhere!
HERE jaguar lists DAC5224E as compatible, and I found this: https://www.auto-doc.it/ad-kuhner/14382651 which is DAC5224 - would this be the same part as DAC5224E? How important is that letter E at the end?
