Lucas Electrics - Fixing a Silent MGB Horn
HTML-код
- Опубликовано: 26 авг 2024
- In this video we take a look at how to fix electrical gremlins in an MGB. The horns aren't sounding, which is a pretty common issue that can be traced to something as simple as a bad connection. It doesn't matter whether you have a Triumph TR6 or a Jaguar XKE; reading wiring diagrams and tracing problems involves the same logical process.
Lucas Electric gets bad press, but in reality the systems were generally well designed and did their jobs. Usually it was an owner's misguided attempts to improve things or misunderstanding of how to fix things that caused most of the issues. Today, that looks like cheap crimp connectors from auto parts stores, incorrectly sized wires, and fuses that don't fit the application.
Follow along as we look at how to read a wiring schematic and fix a set of horns that aren't sounding. For more help with your classic British car, check us out at www.midwestmotoring.com.
Sponsored by
www.krajniakgroup.com
www.loirekrajniaklaw.com
Cool shirt! My wife bought me one of those a couple of years ago and I need a new one but I don’t know where she got it…!
Good explanation as well thank you!
I think that was from a British car show I attended. I've been on the lookout for one too, but can't find it. I would guess Amazon might have something, or maybe it can be made with a Cricut machine?
Great video. I just tackled this issue on my 79 Limited Edition and a few months ago on my 71 MGB. Two differently wired horns. The late MGBs with a single wire connection need a good ground as only power is sent to the horn via the horn button on the steering column. The MGBs with two connectors the Power (Purple wire) is always hot/powered and the ground and activation is at the center steering wheel horn. The 79 issue was a poor ground on a freshly painted and restored car. I ran a ground from frame to the connection bolt of the horn. The 71 that was also a new restoration with fresh paint and under coating issue was the horn push connection light corrosion/ground contact.
I'm still surprised how often electrical issues are the result of something as simple as a loose connection. The system itself is actually pretty reliable and well thought out for the most part.
Adding a relay to the horn (headlights too) is a good idea to prevent the high current going through the switch
The switch is meant to handle the current, but there's a reason they go bad after a while.
Great info. Auto electrical 101. Test light and a multi meter are my friends (but I'd rather rebuild an engine than trouble shoot electrical bugs LoL) and invaluable. Cheers.
Agreed. I like the mechanical stuff too. There's something to the troubleshooting though. I love the logic.
Also, I'm glad to see you say the test light and multi meter are in your tool kit. They're as important as a set of screwdrivers if you own one of these cars!
@@midwestmotoring Indeed! I recently used the test light to trace a no start to a dead electronic dizzy. Replaced with 123Tune dizzy. Love it.
Electricity is Electricity , Lucas electrics have to abide the same rules as everyone elses, you diagnose and fix them the same way. Actually of course just the same as with modern cars it's not the likes of Lucas or Bosch or whoever who are doing the electrical integration it's the car manufacturer so that's another variable in the reliability of the system. At least with most 1960's cars the wiring diagram fits on one page and there is no CAN bus functionality to worry about! Neither do you have any systems that just won't work if some sensor is not working properly. So you've got less excuse for getting stranded at the side of the road than you have with 1990's and up stuff!
Totally agree! I find that (if properly maintained) my Triumphs and the Healey are all at least as reliable as the 2016 "real" car--probably more so.
I have been working on LUCAS gear for 50+ years. There are too many videos, a lot from America that don't help the amateur repairer. A basic understanding of electrical theory also helps. 😊
I have a twelve volt power supply that I attached directly to the horns, and neither one is beeping. They DO make noise like they WANT to beep.....
So my horns are bad.
So long as the 12v can provide enough amps, yes, that's exactly correct. Horns shouldn't take a huge amount of current, so I would agree you probably need new ones. Technically, you can drill out the rivets, separate the horn pieces, clean everything up, reassemble... and it might just work fine.
@@midwestmotoring Neither horn beeped with my power supply. One had a broken off spade connector and that one I took apart and cleaned. It has points in it that I cleaned. I had a new Fiamm horn here so I installed that in place of the one I took apart, and both horns worked. I think my power supply did NOT have enough amps to drive the horn.
That could be. You could always try a jumper wire directly from a battery.
Do you know why the britsh like warm beer?
Because lucas makes refrigerators too.
Love that joke