Herald Alternator Kit and Control Box

[Adrian Girling]

I've just received a Herald Alternator Kit from Rimmer Bros and it looks good.  I tried the online chat to ask if I can simply connect the output to the battery without going via the Control Box as I don't have one, but they had no more information. The instructions which came with the kit explain "it is necessary to link the "+" terminal and the "D" terminal as in the diagram.  Also disconnect the field "F" terminal and the warning light wire "wl" and link them together, but not through the regulator box"

In the diagram the control box terminals are marked:   +  +  F  wl   D  E  - I'm thinking the left hand terminal should be "-" or ground?  Is the "regulator box" different from the "control box"?

My understanding of the function of the control box is to disconnect the dynamo from the battery when the engine is turning too slowly when the dynamo output is below a certain voltage (or the battery sends current through the dynamo) and disconnects it again when the dynamo output voltage is too high.  But I understand an alternator self regulates it's voltage with the current in the field coil.

Sorry for the wordy question (in bold), but I don't want to get this wrong.  I can probably work it out from a schematic of the control box if anyone has on?

Grateful for any help!

Adrian

Edited May 12 by Adrian Girling
missed the word "high"

[glang]

Hi, yes the reg does that and also switches the supply to the dynamo field coil on and off so that the output voltage is kept correct as well protecting the dynamo by disconnecting it if the current draw is too high. All this is explained very well in the free to download Triumph workshop manuals available from Vitessesteve...

[RobPearce]

3 hours ago, Adrian Girling said:

I tried the online chat to ask if I can simply connect the output to the battery without going via the Control Box as I don't have one, but they had no more information.

If the alternator in question is a Lucas type with the three-big-lucar connector (well, two really big, one medium) then the connections are simple:

 - The two really bigs (which are probably internally connected together) have a fat brown wire to battery +ve

 - The other terminal goes to the warning lamp. It should be a brown/yellow wire

However... the wires to a dynamo, in the standard loom, are a fat brown/yellow that goes to terminal D of the control box, and a thin brown/green that goes to terminal F. There's a thin brown/yellow from terminal 'wl' to the warning lamp. Since the need to be a fat wire trumps the colour, the quick conversion does:

 - Brown/Yellow at alternator to the big terminals

 - Brown/green at alternator to the smaller one

 - Fat brown/yellow at control box ('D') to the (three) fat brown wires there ('+')

 - Thin brown/yellow at the control box ('wl') to the brown/green ('F')

If you don't have an intact wiring loom (e.g. if you're building a kit car and starting the wiring from scratch) then I'd follow the first scheme, which is the colour codes used by the factory when an alternator was fitted.

Edited Thursday at 19:45 by RobPearce

[Adrian Girling]

15 hours ago, RobPearce said:

If the alternator in question is a Lucas type with the three-big-lucar connector (well, two really big, one medium) then the connections are simple:

 - The two really bigs (which are probably internally connected together) have a fat brown wire to battery +ve

 - The other terminal goes to the warning lamp. It should be a brown/yellow wire

Thanks Rob, yes it's as you describe.  I'd use the existing wiring loom if it existed, but since it's missing I'm starting from scratch, probably adding a fuse box etc.  I think you are confirming that I really can just connect the two big connectors to the positive side of the battery and the other terminal also via the warning lamp (and presumably the ignition switch) also to the positive side of the battery like the attached picture?  Presumably this means that the alternator self regulates to around 14.2 Volts maximum?

[RobPearce]

That's right, the alternator has a built-in regulator. It needs the warning lamp connection (and a proper filament bulb, not an LED) to get the field windings kick-started. Your wiring diagram is pretty standard - all the brown wires feeding permanent live loads come off the solenoid simply because it's a more convenient terminal than the battery, and it means there's only one (big fat) cable to each of the battery terminals, which is easier for when you need to change it.

[Adrian Girling]

14 minutes ago, RobPearce said:

That's right, the alternator has a built-in regulator. It needs the warning lamp connection (and a proper filament bulb, not an LED) to get the field windings kick-started. Your wiring diagram is pretty standard - all the brown wires feeding permanent live loads come off the solenoid simply because it's a more convenient terminal than the battery, and it means there's only one (big fat) cable to each of the battery terminals, which is easier for when you need to change it.

Rob, you are a fountain of knowledge, most grateful 👍

[Adrian Girling]

Well, I finally got around to installing (or trying to install) the alternator kit, but the adjustment bracket Rimmer Bros sent me (to set the tension in the fan belt) is not correct.  See the photo of the bracket they sent, and a photo of the diagram in the installation instructions which clearly shows a longer bracket which extends further to the right to allow the alternator to be moved away from the engine.  Rimmer Bros have not replied to emails but I finally got to access their web chat where they insisted I had the right part for the Triumph Herald.  But the person with whom I was chatting suggested I could use a longer fan belt, confirming he didn't understand the problem.  He said they don't stock a longer bracket.

Has anyone successfully installed their alternator kit in a Herald?  If so, any chance you could send a photo of the bracket on your car?  I doubt they actually make this part, so I'm hoping to find a picture of a longer bracket to show them

[RobPearce]

That looks like a very poor copy of the original (alternator) version of the bracket.

Better copies are available from Paddocks and others. They look like the one in the drawing. I think I have one lying around somewhere, although I may have fitted it to my Spitfire, but I can certainly try to photograph the one on my Vitesse, if that's correct.

I've seen people do the conversion without needing that adjuster, as it's possible to re-use the (longer) dynamo version with an appropriate (longer) fan belt. But I get the impression you aren't actually converting from a dynamo but rather building a kit car from scratch.

[RobPearce]

OK, I've been out to check, and I will revise my opinion.

Here's the one I have in stock, from Paddocks:

That looks very much like the one you got from Rimmers.

Here's what my Vitesse has:

That's the late Spitfire / Dolomite / big saloon type, and it's not very much different from the new offering... but is a little, and probably significantly.

I obviously didn't fit the new one to the Spitfire. Here's what it has:

That, I believe, is the original dynamo type that was on the Herald we had briefly fitted this engine to.

Edited yesterday at 15:41 by RobPearce

[Adrian Girling]

Thanks Rob.  I'm seeing that your Vitesse bracket is right up against the end leaving no more room for tightening the belt. And the original Herald dynamo one looks as if it would be long enough - I'd use that if I had it, but it was missing and the dynamo was tight enough without it, rusted in place!  I doubt Rimmer Bros will be any help - you only have to look at Trustpilot and other online reviews to realise how hopeless, even downright rude they are to customers.  In the end, a cheap lesson to learn - I will buy a universal one online as there are several straight brackets for this purpose of different lengths.  I'll check out Paddocks for parts in future, won't be going back to RB.  Maybe there is a forum section for supplier experiences - if not, I'd like to recommend one.

[glang]

I dont really understand what the problem is because it looks like that is the bracket supplied with the kits from different suppliers so are they all wrong? Is it that the alternator cant be moved close enough to the engine to allow the bracket slot to be used to fit the bolt? If thats not the case surely you just need the right length belt as maybe youve been sent the wrong one. Various suppliers say the 11060 is the one for a Herald/Spitfire with alternator rather than the standard 11025  but theyre available in a great range of lengths so you should be able to find exactly whats needed...

[RobPearce]

I think the problem with the currently available bracket is that, because the bit that fixes to the head is at the wrong angle, there's only about half an inch of the slot which doesn't involve an interference fit between the alternator and the block/head/spark plugs. That makes getting the right belt a bit tricky.

[glang]

wow loads of these kits must have been sold and the suppliers need to be told theyre not correct then! Rimmers have the dynamo bracket pt number 121215 which looks very similar to the one in your last photo Rob...

[Adrian Girling]

Thanks Glang and Rob, I'll get back to my shed this afternoon to do some measuring, and check the part number of the belt supplied, which is slightly longer than the belt I took off.  Annoyingly, the 121215 bracket looks as if it might work but Rimmer Bros insisted they don't have a longer bracket, although it doesn't have the S bend in it, presumably necessary to pull the alternator forward to bring the three pulleys into the same plane.

I will measure the distance from the hole in the engine block to the hole in the alternator when the alternator is pulled so that the fan belt is about right.  With a slit about 60mm long it'd be nice to find a length where the alternator bolt is roughly in the middle of the slit.

I do wonder why it's such a complicated shape on the side with the 28mm dia hole in it?  I'll be checking if a simple straight bracket with hole and slit will fit - the hole for the block bolt of the supplied bracket is about 30mm away from the line of the slit.  To get the three pulleys in the same plane it may be necessary to put the S bend in it to give it the 10mm offset of the bracket provided, or maybe just a bolt/washer(s) spacer(s).

 

[Pete Arnold]

For what it's worth here's a photo of the alternator & bracket, which I purchased from James Paddock a few years ago, as fitted to my Vitesse.

The fan belt I use is Gates 6222MC (or equivalent) and its size is AVX10 x 1050La.

[glang]

Stick with it Adrian as I find it hard to believe so many kits have been sold and youre the first to find a problem with the bracket🤔

[Clive]

23 minutes ago, Adrian Girling said:

 

I do wonder why it's such a complicated shape on the side with the 28mm dia hole in it?  

 

That is used as the front engine lifting eye.

There are a variety of brackets that will likely fit, and people have used "rod ends" to fit them too, they are great for taking up misalignement. Similar to

[Adrian Girling]

38 minutes ago, Clive said:

That is used as the front engine lifting eye.

Thanks.  Even at my great age I'm learning so much!

[Rosbif]

5 minutes ago, Adrian Girling said:

Even at my great age I'm learning so much!

Never too old to learn. Actually at my age I need to relearn the things I've forgotten. 😵

[RobPearce]

2 hours ago, Adrian Girling said:

To get the three pulleys in the same plane it may be necessary to put the S bend in it to give it the 10mm offset of the bracket provided

Yes, or you can do what I did on the Spitfire. If you look closely at my third photo you'll see that the bracket is fitted to the "wrong" side of the alternator lug, which fairly accurately accounts for the 10mm error. 🤫😜