Dynamo regulator - tips for revival?

[Timleech]

Trying to revive a (big) dynamo charging system that hasn't done any work for 10 years or more.

After flashing the dynamo to get it started once, it still needed help on some other occasions and charge rate/ voltage seemed distinctly low. I suspect dirty contacts on the regulator, but could do with some advice on quick & dirty methods to get it working somewhere near right in case simple contact cleaning doesn't do the job. Proper servicing/resetting can wait for another day.

 

Dynamo is CAV 24Volt type D8C 14MX

regulator is labelled

" Compensated Voltage Control Type 37F - 28SM"

 

(Also marked 'Regulator has been correctly adjusted - Do not alter')

 

It's a 3-coil regulator, the RH coil appears to be the current regulator and might be the source of the trouble.

 

Anyone know what sort of current and charge voltage this setup should be capable of?

Pics available if required.

I've got a spare regulator, but it's been sitting out in the weather for a few months and I've no idea what its condition was before that

 

 

Thanks for any help

 

Tim

[casper ghost]

I don't know much about regulators but my Dorman has one and the previous owner changed the standard regulator for the type normally on an alternator. Means little to me, i'm trying to think of a way to replace the dynamo with an alternator.

Casp'

[john4647]

Does the regulator look like this?

 

[Timleech]

Yes and no. It's got the three coils but extra bits that look like heater coils (presumably the 'temperature compensation' part) and bigger than I imagine that to be. If I get time later, I'll post a picture.

 

Thanks

Tim

 

 

Does the regulator look like this?

 

[Timleech]

If I get time later, I'll post a picture.

 

Et Voila!

 

 

 

Tim

[jelunga]

Et Voila!

 

 

 

 

 

Tim

 

Of absolutley no use to the OP, but what a lovely piece of kit!!!

[john4647]

Yes and no. It's got the three coils but extra bits that look like heater coils (presumably the 'temperature compensation' part) and bigger than I imagine that to be. If I get time later, I'll post a picture.

 

Thanks

Tim

 

Tim, I think that what you have are regulators BJ and BLT.

They will be the same settings (mechanical and electrical) as the standard 189A control board.

If it is any help, I could scan the workshop manual and e-mail it to you.

 

Alternatively, if you wish to renew the regulator, there are Solid State versions available from the Diesel train fraternity.

 

Regards, John

[Timleech]

Tim, I think that what you have are regulators BJ and BLT.

They will be the same settings (mechanical and electrical) as the standard 189A control board.

If it is any help, I could scan the workshop manual and e-mail it to you.

 

Alternatively, if you wish to renew the regulator, there are Solid State versions available from the Diesel train fraternity.

 

Regards, John

 

Thanks for that, it might well be helpful.

Current state of play is that I've cleaned up the current regulator contacts, but had to remove the moving contact assembly to do so and thereby lost the adjustment. I've played around to get some apparently sensible results, but it would be better to be able to do it a bit more scientifically.

 

As for replacement, if it came to that then replacing the dynamo with an alternator might make more sense. Not a simple matter, though, in this case and not my decision.

Many thanks

 

Tim

[john4647]

Thanks for that, it might well be helpful.

Current state of play is that I've cleaned up the current regulator contacts, but had to remove the moving contact assembly to do so and thereby lost the adjustment. I've played around to get some apparently sensible results, but it would be better to be able to do it a bit more scientifically.

 

As for replacement, if it came to that then replacing the dynamo with an alternator might make more sense. Not a simple matter, though, in this case and not my decision.

Many thanks

 

Tim

 

Tim, I have now scanned the workshop manual and created a pdf file. Can you PM me your e-mail address and I will forward it to you.

 

I don't know how to post a pdf file on here?

 

Regards, John

[pejjo]

John, do you still have this scanned manual? I have problems with a similar one, 37F-38N

[bizzard]

Et Voila!

 

 

 

Tim

I'm not conversant with that particular regulator but dynamo regs are all similar.

One of those coils with contact breaker will be the cut out for when the dynamo is not being driven fast enough to charge (engine on tickover). the contact breaker on that coil should click closed when charging and open when not chargng. The coil at the other end is normally the voltage regulator coil and should be adjustable (is that brass screw at the back of it an adjusting screw ?) To check and adjust the charge rate using a volt meter you would have the engine ticking over. The cut-out coils contacts points should be open (not charging) place the volt meters +pos lead which needs like a flat male spade terminal on the end or just flatten the bare wire end and slip it between the two cut-outs contact breaker plates, clip the -neg onto the earth terminal. Rev the engine to which would be roughly its max charging speed. Now I can't remember the exact charging voltage that the meter should read, on 12v vehicles I think it was 14.6v so I'd say if its below 14v take it up a little at a time whilst the meter is still connected between the cut-out coils contacts. The adjustment will almost certainly be on the voltage regulator coil which is normally the one at the opposite end to the cut-out and should have an adjustment screw probably C/W to increase the charge rate.and A/C/W to decrease. When adjusted remove the volt meter wires and check output at amp meter, but that reading will only of course be true to the state of charge of the battery. All the old 12v vehicle Lucas, Delco 3 and 2 coil regs adjusted in this manner, some had a screw adjuster, some used a special key. Sorry its a bit vague but it was a long long time ago when I did this adjustment regularly.

What charge rate adjustment voltage setting for your 24v system would be I don't know.

Edited October 12, 2013 by bizzard

[Arthur Brown]

I remember a warning to clean the contacts with sand paper but NOT emery as the particles of emery are semiconductive and mess up the regulation.

[Timleech]

What charge rate adjustment voltage setting for your 24v system would be I don't know.

 

That one has been working fine for 3 years now, following John's help with the instructions. Those regs are a bit more complex than Biz describes, and I wasn't in a position to do the full setup but did get it to be good enough for practical purposes.

 

 

Pejjo, if John doesn't come back to you I should still have the file he sent me, somewhere in the darker recesses of my computer

 

Tim

[16csvt]

Sorry to reopen an old thread, but I have need to sort out a regulator of this type, with D8C dynamo, as fitted to

http://www.flickr.com/photos/16500518@N05/7542256562/in/set-72157630296231684

 

I have studied an apparently similar regulator to that fitted to the crane, but for dynamo D07 x 24 Low speed.

 

Those of us of an age will no doubt remember the lucas 2 bobbin (early minis', morris 1000 and the like) and the lucas 3 bobbin (??RB340?? austin 1100 and others).

Careful examination of the 'similar' regulator seems to suggest perhaps a two field design. There seems to be a 'cut out' (on the left in the previous photos), and TWO seemingly identical voltage regulator bobbin circuits (center and right). Both the field connections come out as DF1 and DF2.

This seems a little strange. Are the associated dynamo's capable of accepting two field circuits, in order to produce two independantly regulated 'D+' outputs??

There seems to be very little info about these old machines around on the t'interweb, if any of the previous contributors have recently spotted the tech info files mentioned I would be most obliged to receive a copy of them.

Does anyone have info on the dynamos' D8C and D07 x 24??

Kindest regards

Kevin

(Actually, I'm desperate for ANY relevent calibration / circuit info, but I'm trying not to beg too hard.....It is not becoming in a first post!)

[Per Ivar Berntsen]

On 12/10/2013 at 20:17, Timleech said:

 

That one has been working fine for 3 years now, following John's help with the instructions. Those regs are a bit more complex than Biz describes, and I wasn't in a position to do the full setup but did get it to be good enough for practical purposes.

 

 

Pejjo, if John doesn't come back to you I should still have the file he sent me, somewhere in the darker recesses of my computer

 

Tim

Hello ,IS ut possible to get a copy og the flis regjering car dynamo. I got one that do t charter in a 1957 Scania bus. Regards Per Ivar Berntsen 

[AndyW]

On 03/12/2010 at 09:40, john4647 said:

 

Tim, I have now scanned the workshop manual and created a pdf file. Can you PM me your e-mail address and I will forward it to you.

 

I don't know how to post a pdf file on here?

 

Regards, John

Hi, I know it is a long time since the OP but I have exactly the same dynamo and regulator which is mounted on a Kelvin R4 engine and I'd like to get it cleaned up and working. Is there any chance that the pdf copy of the workshop manual is still available?

[BEngo]

Tim Leech is, unfortunately, no longer with us.

Sir Nibble of this patch may well be able to help with setting up.

Kelvin R4 is nice.  I saw the R2 once - that would have made a good narrowboat engine but they only ever made one.

 

N

[Sir Nibble]

Seriously? I've just read back through the thread, I used to do the D7 split field things. Not got any info and I wouldn't dream of making any statements based on memories over 40 years old!

[Tony Brooks]

Just looked in a REME training precise in the hope the Landy FFR control box would deliver some clues but that was a dead end. I also looked in a Vehicle electrics text book published in 1958 but that went big on Simms 24v control boxes and it had no settings for either so sorry I can't add anything to what SirN said.

 

Trying to be as helpful as I can but entirely at your own risk. Have a read through https://www.traction-owners.co.uk/wp-content/uploads/2017/01/LucasGeneratorOutputControl.pdf

 

Double any voltage readings for your 24 volt unit but the air gaps are likely to be similar but BEWARE - I have a horrible feeling that CAV dynamos may work the opposite way to Lucas ones. That is with the field coils being earthed via the regulator rather than being fed from the regulator. Don't take that as gospel though. Read the website bearing it in mind.

[john4647]

This may help.

 

https://www.ebay.co.uk/itm/362982127782?autorefresh=true

 

See diagram on pictures supplied in the listing.

[Sir Nibble]

23 hours ago, Tony Brooks said:

Just looked in a REME training precise in the hope the Landy FFR control box would deliver some clues but that was a dead end. I also looked in a Vehicle electrics text book published in 1958 but that went big on Simms 24v control boxes and it had no settings for either so sorry I can't add anything to what SirN said.

 

Trying to be as helpful as I can but entirely at your own risk. Have a read through https://www.traction-owners.co.uk/wp-content/uploads/2017/01/LucasGeneratorOutputControl.pdf

 

Double any voltage readings for your 24 volt unit but the air gaps are likely to be similar but BEWARE - I have a horrible feeling that CAV dynamos may work the opposite way to Lucas ones. That is with the field coils being earthed via the regulator rather than being fed from the regulator. Don't take that as gospel though. Read the website bearing it in mind.

No, cav were always+ve regulation. I'm not sure it's something I would want to muck around with these days.

[john4647]

Wiring diagram shows field to Pos regulation and dual field circuits.

[Sir Nibble]

2 hours ago, john4647 said:

Wiring diagram shows field to Pos regulation and dual field circuits.

Yes, the split field as it was called. Those old dynamos were very reliable and hardly ever gave trouble but when they did, it was big trouble. Hooray for alternators! Bloody things put muscles on me!

[AndyW]

Wow! Thanks for all the detailed information. 24 hours creates a lot of head scratching and chat in the workshop. After discussion with a manufacturer I am now considering putting a modern electronic 12V regulator onto the CAV dynamo and having 12V electrics apart from the starter which will be 24V via some sort of solenoid actuated series battery system that I have yet to invent. A 12V CAV BS5 starter is an option to simplify everything but it is £300 and only half the power of the 24V version which is in perfect working order. Got to get my head around split charging all three batteries (starter 1, starter 2 and domestic) at 12V via VSRs too.

[Tony Brooks]

13 minutes ago, AndyW said:

Wow! Thanks for all the detailed information. 24 hours creates a lot of head scratching and chat in the workshop. After discussion with a manufacturer I am now considering putting a modern electronic 12V regulator onto the CAV dynamo and having 12V electrics apart from the starter which will be 24V via some sort of solenoid actuated series battery system that I have yet to invent. A 12V CAV BS5 starter is an option to simplify everything but it is £300 and only half the power of the 24V version which is in perfect working order. Got to get my head around split charging all three batteries (starter 1, starter 2 and domestic) at 12V via VSRs too.

 

I think some Merc vans had a ready made system. As the 2 x 12V batteries you use to provide 24 volts will only be put in series when starting the split charging should be easier. May be 2 VSRs.

 

How vital is it to keep the dynamo? I think a 24V alternator would be easier all round ans I think SirN may have  a similar view.