TRExp

Odds & Ends Forum

Horns, Hooters and Lucas

Moss Motors
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor

Yellowhawk Valley Avatar
walla walla, washington, USA   USA
1969 Triumph Spitfire "Walla Walla"
1969 Triumph Spitfire "Portland"
1972 Triumph Spitfire MkIV "Spokane"
1975 Triumph Spitfire 1500 "Dayton"    & more
These comments apply to any of the cars that happen to use either Lucas or Clear Hooters brands of horns. As seen in the photo I recently inherited a box of horns in questionable condition (thanks Hazen and Kyle).

When I started I think it was 4 of them would operate. The others would make no noise at all. There is a mixture of Lucas 9H units, one Lucas 7H, and several Hooters brand. A common failure among them was simply that the inner relay needed to be adjusted to allow the movement both ways of the plunger and plate disc. Several of them were also considerably rusty inside but that does not in itself stop them from working.

I will caution anyone opting to adjust them to be very cautious and slow when getting the screws to turn. The Lucas units use a very small, perhaps a #6 screw, the Hooters in larger and not as likely to twist off. I suggest applying some good solvent of your choice to the screw and letting it sit for a day. The grab it with a good tool so you don't wear off the flats and slowly work it back and forth in very small pressure increments. I was successful with all 5 of the Lucas units in getting those to turn and adjust. Another special thing at least with the Lucas units is that the screw is a Left Hand thread. I have to go back and look at the Hooters pieces and see what they are for sure.

How do you know which way it has to go? I found on all of them that I could guess but after looking at my notes I think the best guess in made by listening to what it is doing. If you apply12v to both terminals and nothing is happening, that usually meant that the points are too "high" and the plunger is holding them open. If the unit just clicks, that usually meant that it was pulling the plunger in correctly but that the relay was not high enough and it was not breaking the points when it moved. On the left had threads, that means CCW pushed it up, and CW pulls it down. (These Lucas units have the threads in the housing. The Hooters screw is in a fitting in the housing the screw is threaded into the points assembly frame.

Another issue I found on 2 or 3 of the units was the obvious melting of the pull-in coil insulation in the bottom of the plunger well. These were all bad enough that the plunger would not move. On one I had to pry and work the plunger out of the well. On another, it was stuck in the neutral position and would not press down, so it would obviously not pull in with the coil. I was able to correct all of them. I thing this is a sign of overuse of the horns which actually heat up very fast. A long application of the horn is not recommended. Perhaps just a lot of quick beeps.

I will add some photos of a few things tomorrow after I get them catalogued.

Dan

. Hide banner ads & support this website by becoming a > Gold Supporting Member <

Attachments:
Horns general13.jpg    54.5 KB
Horns general13.jpg

Smoothbrain Avatar
Smoothbrain Silver Member Thomas Nelson
Bettendorf, Iowa, USA   USA
Hi Dan,
These are the non-working horns from my car. Replaced with black plastic monotone jobs.
If I can get these working again, they will go back on and I'll recover that cheerful two-tone sound.
Appreciate your post!



Tom


Thomas Nelson
Bettendorf, IA

1970 Spitfire Mk III


Attachments:
image.jpeg    45.2 KB
image.jpeg

Yellowhawk Valley Avatar
walla walla, washington, USA   USA
1969 Triumph Spitfire "Walla Walla"
1969 Triumph Spitfire "Portland"
1972 Triumph Spitfire MkIV "Spokane"
1975 Triumph Spitfire 1500 "Dayton"    & more
Glad you posted here. I will grab a few pics and some info and get it back here tonight or tomorrow.
Dan

. Hide banner ads & support this website by becoming a > Gold Supporting Member <
Yellowhawk Valley Avatar
walla walla, washington, USA   USA
1969 Triumph Spitfire "Walla Walla"
1969 Triumph Spitfire "Portland"
1972 Triumph Spitfire MkIV "Spokane"
1975 Triumph Spitfire 1500 "Dayton"    & more
Quote: Hi Dan,
These are the non-working horns from my car. Replaced with black plastic monotone jobs.
If I can get these working again, they will go back on and I'll recover that cheerful two-tone sound.
Appreciate your post!
Tom

Thomas Nelson
Bettendorf, IA

1970 Spitfire Mk III


Got the paper done tonight. It is attached as a pdf. Good luck with it and the horns,
Dan



Edited 1 time(s). Last edit at 2017-10-27 10:46 PM by Yellowhawk Valley.


Attachments:
Hoping to repair your Clear Hooter horn.pdf    421.9 KB

. Hide banner ads & support this website by becoming a > Gold Supporting Member <

To add your reply, or post your own questions

Members Sign In   or   Create an Account

Registration is FREE and takes less than a minute!


Having trouble posting or changing forum settings?
Read the Forum Help (FAQ) or contact the webmaster