A DIN relay retails for $5, and gives essentially lifetime service. So we’ll add $10 as the price for a nice plated tin case, let’s say $15-20 seems right. But you’re correct, they sell for as much as $150. My relays have been rebuilt many times, but are approaching the end of the road after half a century, so I’m trying to address this before it’s a crisis. Remember that these are used on all British cars, and probably on many continental makes. We’re all in the same boat So why hasn’t something so simple been reproduced?
In looking online, there seem to be several Lucas branded relays under $80. But I have no idea if any will last, or if they are mechanical or solid state.
Tom
Julian Barratt is a frequent contributor on the etype uk forum. There is actually a thread dedicated to discussions about things sng. Perhaps a suggestion could be made to him that sng consider manufacturing a few reliable relay versions?
6RA is simply a style. Lucas made them in a bewildering jumble of specifications. There were SPST (on/off), SPDT (changeover), common power, 12V, 24V, neoprene sealed, continuous and intermittent versions. And weirdly, positive and negative ground, which simply had the labels reversed. There was a special 6RA relay just for the rear window defogger. All 6RA’s are rated 240VA, which means 20A continuous current for all 12V applications.
I don’t know if all of them are junk, that’s what I’m asking. The one in your photo appears to be the same as the ones I just returned, but for the paper label. In GB, there’s a similar relay with the Lucas name stamped into the can. It’s made or repackaged by one of the current pretenders to the Lucas trademark. I was hoping that one of our friends over the water could report on these. I really don’t want to acquire a bunch of junk from around the world. If there is no answer here, I’ll try calling around.
Mike,
Is your issue with the contacts wearing out? If so, would it not be possible to either find similar pieces in other relays where the thing can be adjusted to fit the 6RA? Either that or get new contacts made and installed?
Like Nick, I have a '68 and have cleaned the points maybe twice in my 24 years of ownership, I actually only remember one time, but maybe twice. Pretty darned good piece of kit IMO.
My problem is more mundane. When I took them apart this time, the cork gaskets were toast. Probably never watertight anyway. For now, sealed with rubber cement. The points can be filed until there are no points or until the armature reaches a breaking point, but beyond a certain point, it’s pointless. In half a century, I can only remember one having a bad winding.
I can look on my parts Rovers to see if they have good used ones, if anyone wants.
PM me.
I tried the Lucas branded relay from SNG, and I’m pleased to say, it’s good. I didn’t disassemble one, but the rather loud click suggests that it’s not a microrelay tucked into a can. The bottom is potted in clear silicone, and should be waterproof for a long while. The windings measure 83 ohms, so fine for continuous or intermittent use. The box and the relay are marked with date codes. My only nit is that the terminal markings are obscured by the silicone. And best of all, no shorts or bridging of the contacts. Done.
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Found this on Amazon. Is the price similar to what you paid from SNG?
https://www.amazon.com/Lucas-W0133-1622025-LUC-Electrical-Relay/dp/B0044E9CG6
No. Not only is it more expensive, it’s random luck whether it’s a the real deal or more like the fake product I originally bought.
Why not do away with the relay entirely - make a small PCB using a power MOSFET that can solder directly to the original Lucas board and terminals. That should outlast the whole rest of the car, if done properly.
Regards,
Ray L.
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40+ years ago I was taught that if a fuse is used to protect a solid-state device… The solid-state device will protect the fuse. It’s amazing what they have done with MOSFETs in the last 10 years. But they still have more of a voltage drop than a set of nice clean relay contacts.
For goodness sake. I wasn’t looking for a project, I just wanted to buy my baby pretty things!
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No good deed goes unpunished. 
Shoulda led with that, Mike.
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Mike a question on relay’s. I’ve got an aftermarket rad fan in my Ser I and it has a big draw on startup. I’ve wired it directly from the battery through an in line fuse to a cube relay with 30 amp capacity. In this setup the motors are cold. Is it better to wire the relay in after the motors (motors are now continuously hot) as the load going through the relay is now lessened? I note the Ser II cars with the twin fans are wired with the relay before the motors.
Amps is everywhere. You won’t reduce current by putting the relay on the ground side. If it works, just leave it be. If you feel the load is very high, consider one of these Mercedes fan relays, which can handle 40A continuous, and have an integral fuse:
I used the original housings and ‘filled’ it with electronics.
For the horn and other stuff a single PROFET will do the job.
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I had the same problem last winter, replaced the wiring harness and all relays.
Relays were sourced from one of the usuals, arrived in plain white boxes with part
number printed on end flap.
Upon testing 2 of the relays failed, found same problems internally, bad solder joints
and solid state relays in place of the coils.
Ordered all new relays from SNG, arrived in traditional green and white Lucas boxes.
I noticed the Lucas relays weighed much more than the ones initially installed.
Tested coil resistance on Lucas relays - very close to original.
Jag has been on the road for 6 months, no problems.