Updating Electrics in a Herald 13/60

[Alan Armstrong]

I've seen some of what i'm referring to here already...but my question in 2 parts is: ....now that I'm going to install an alternator over a dynamo, I believe the voltage regulator is now redundant?

Therefore having the space on the bulkhead, is it advisable to replace it with a fuse box?

Maybe this is overkill as these cars have survived without a fusebox for 50+ years🙂

Would appreciate your comments

[glang]

Are you sure theres no fuses at all? I thought every model had at least 2 or 3 - mines behind the battery and then theres an inline fuse holder up under the dash. I know many have further split up the circuits and separately fused each one using a new box which of course is no bad thing... 

[Clive]

There may be a single inline fuse somewhere....

But yes, fitting a fusebox is a good idea, and should be able to provide basic overcurrent protection.

[RobPearce]

1 hour ago, glang said:

Are you sure theres no fuses at all?

1200 Heralds had no fuses at all but the 13/60 got a single inline one for the headlamp flash.

Adding some is probably a good idea.

[Wendy Dawes]

When the loom was removed from my 1200 for replacing burnt wiring from a previous electrical fire before I bought it, we put in line fuses on the horn, lights and ignition as a safety precaution and as said, no fuses on the 1200. I also fitted a battery isolator onto the negative lead so the battery is disconnected when the car is parked up 

i think my 13/60 did have one fuse on the lights as I recall cant remember if there were any others, didn’t keep it for long. 

Edited September 21, 2022 by Wendy Dawes

[Rosbif]

Just the 1 fuse on a 13/60. 

[glang]

20 hours ago, Alan Armstrong said:

Maybe this is overkill as these cars have survived without a fusebox for 50+ years🙂

Think fuse protection becomes even more important as the years go by😬

[ferny]

You're right next to the battery too, so it's an ideal time to cut into curcuits and add any relays you may want.

 

When you add fuses, think about sensible circuit splitting as it can help fault find. As an example - my wipers stopped working once, but because they were on the same fuse as my radio constant but not my heater or headlights I was able to diagnose the fault whilst driving. No wipers or radio but still have lights and a heater? Ahha, it's just that circuit so let me check the fuse first. Etc.

[Rutty]

I recently upgraded the fuses on my Vitesse. I found it useful to have two fuse boxes one for the permanent live circuits like lights, horn, etc and one for the circuits that switched on with the ignition l, i/e indicators, brake lights, etc.

[Alan Armstrong]

Great comments...thank you all.

Alan

[JumpingFrog]

One more thing to add that nobody mentioned, if you're updating the electrics. It's well worth adding relays for the headlights (one for dipped, one for high), your lights will be much brighter (add a real earth from the bonnet too) and will avoid high currents through the feeble dash switches which could also help protect you from wiring fires.

[Clive]

Worth remembering that fuses usually blow from catastrophic failures, ie dead short. And the fuse is there to blow before the wiring gets damaged. 

Essentially:

The field/WL (brown/yellow) are just joined

Main brown wire from the battery via solenoid, join to the Brown/green from the dynamo(alternator) That joint can be the live supply for the car, so a fusebox with a common terminal one side of the fuses is good.

Brown horn supply, 35A blow fuse

Brown/blue to light switch 35A blow

Brown/blue to ignition switch 35A blow

Beware the difference between continious and blow ratings on fuses. blow is about twice continious rating, even then it will take a few seconds. However, on a dead short, the current flow should be VERY high (100+ amps) so it will blow much faster.

It is not a bad idea to then use additional fuse box(es) to protect individual circuits as required. My own car runs a number of 10A and 15A fuses.

 

[Howard]

Be very careful with your fuse ratings since modern fuses are differently rated to the original Lucas fuses. The attached sheet includes a comparison chart for reference:-

UK DHC 1981 TR7 2022-09 Sht 6.pdf

 

Edited September 22, 2022 by Howard
Formatting problem

[JumpingFrog]

29 minutes ago, Wendy Dawes said:

However there are no relays in the lighting circuit, can anyone recommend which type and where they should be as I want to make sure there are no issues with current

There won't be any issue with current, the H4 halogen bulbs and sealed units are roughly the same power rating.

If you want relays just to take the load off the dash wiring and make the lights brighter, you need to minimise the wire distance between the battery and the light. I think the neatest place to fit relays is on the bulkhead behind the battery. You cut the original blue/white (high beam) and blue/red (dipped beam) wires here such that the switches energise the corresponding relay coil. Add new fused feeds from the battery positive to one side of each relay's NO contacts, and connect the existing blue/white or blue/red to the other.

Each relay needs to have a current rating to handle the power of both bulbs, for a 60W bulb, 60/12=5A. But this is for one bulb, so 10A. A classic Lucas 6RA relay handles up to 20A so would be fine. Or use a modern relay of a similar rating.

Edited September 22, 2022 by JumpingFrog

[glang]

2 hours ago, Wendy Dawes said:

Just a quick question,  my 12/50 was upgraded to halogen with pilot sidelight in the headlights before I bought it, so now just has indicators with normal bulbs in the original side/indicators.  However there are no relays in the lighting circuit, can anyone recommend which type and where they should be as I want to make sure there are no issues with current 

You could turn on the main beam lights and using a multimeter measure the voltage difference between the bulb +ve connector and the battery +ve terminal to see how much of a voltage drop your getting with the existing wires, connections and switches. That will tell you if therell be much improvement in light output with relays although probably not how much the switches are suffering...

[Wendy Dawes]

Thank you both your advice is much appreciated. That’s a job to get done in winter layup

which isn’t  far away 😟

[RobPearce]

9 hours ago, JumpingFrog said:

If you want relays just to take the load off the dash wiring and make the lights brighter, you need to minimise the wire distance between the battery and the light.

Well, what you actually want is to minimise the wire distance around the full circuit from power source to bulb and back. However, in normal running it's arguable that the power source is actually the alternator (especially if it's a machine-sensed type like most). My Vitesse has the headlamp relays powered from there, which works fine.

[mk2vitesses]

I fitted an alternator to my 13/60, I would strongly advise fitting more fuses. The feed from the starter relay goes unfused to the ignition switch, should the switch come lose there is a nice metal strap waiting to short out the battery feed!

I fitted a 60A in line as shown in the pictures, you can run the output from the alternator straight to the battery.

[Wendy Dawes]

11 hours ago, RobPearce said:

Well, what you actually want is to minimise the wire distance around the full circuit from power source to bulb and back. However, in normal running it's arguable that the power source is actually the alternator (especially if it's a machine-sensed type like most). My Vitesse has the headlamp relays powered from there, which works fine.

Forgot to mention I’m still running from a Dynamo not alternator 

[RobPearce]

1 hour ago, Wendy Dawes said:

Forgot to mention I’m still running from a Dynamo not alternator 

OK, that makes a difference, because the dynamo relies on the control box for regulation, and that's located behind the battery. For a dynamo you probably do want to take the headlight feed from the solenoid.

[Wendy Dawes]

5 hours ago, RobPearce said:

OK, that makes a difference, because the dynamo relies on the control box for regulation, and that's located behind the battery. For a dynamo you probably do want to take the headlight feed from the solenoid.

Thanks Rob much appreciated 

May do alternator conversion over the winter, it’s negative earth so should be fairly straightforward 👍

[Matt306]

May two penneth when i had a Herald... 

Yes definitely Alternator over a Dyno.

Put a fuse box in... 2 fuses was an economy and a modern 12 blade fusebox is cheap as chips.

After that go relays on the lights protect the old wiring and old switches.

When you have done that you can go modern 7inch Halogens or LED (less current draw although the relays will protect)

 

[Wendy Dawes]

Winter lay up job ahead 👍

Edited September 23, 2022 by Wendy Dawes

[Rutty]

On 23/09/2022 at 14:23, Wendy Dawes said:

Thanks Rob much appreciated 

May do alternator conversion over the winter, it’s negative earth so should be fairly straightforward 👍

If you want to keep it looking original but want an alternator then you could go for a Dynamator. They do cost more but bolt straight on rather than having to buy or make conversion brackets for standard alternators.

[mk2vitesses]

2 hours ago, Rutty said:

If you want to keep it looking original but want an alternator then you could go for a Dynamator. They do cost more but bolt straight on rather than having to buy or make conversion brackets for standard alternators.

You should still upgrade the wiring as the output is much greater than the dynamo.