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And Cut Down On In-Traffic Finger Exercises John La Barbera deaver@otherside.com I've owned Volvos in one form or another since 1972 and can say with confidence that I've tackled every kind of repair necessary to keep the beasts running. I should clarify that statement by saying that my experience is limited to the 122 (Amazon still doesn't seem right) and the 1800 series. In my early days these repairs were a matter of survival but today they're a labor of love. I recently put a 122 4-door on the road (a parts car) for my son to use until we can get his "good" 122 painted and ready for the road. A neighbor put an anonymous note in the mail box about an ordinance against "junk" cars (how dare they!) and "jalopy" vehicles (better, but still an insult). So we decided to get it roadworthy and field test all the new drive-train stuff from Volvo and ipd that would eventually go into the restoration project. Everything went smoothly, including swapping out the BW 35 slush-bucket tranny for a M40 stick. I'd done this before (in the gravel driveway, in the winter, with newly married, budget tools -- i.e vice grips, crescent wrench -- you get the picture) and was ready for all the roadblocks. However, the horn ring contact threw me a curve. I'd never had to fix one of these things before and after three tries I sort of gave up. I couldn't find material that would insulate the two wafers that make the electrical connection. I won't even try to describe the results of squeezing butyl caulk in between the two hungry metal disks. It seemed salvation was in sight when I came across the RPR link from the Volvo Classics web page. I figured my troubles were over. The bubble burst when they told me they were sold out of their horn ring repair kits; "sold all 100 unit allotment last month." I'm not making this up, but my eyes fell to the mouse of my office computer at that very instant and sitting underneath it was my solution. The mouse pad is the perfect insulating material for the job. These come in various "flavors," but basically you'll find a thickness from about 3/16" to 1/4" (you do the math for metric). By the way, before you start tearing out the horn ring, make sure your problem is not the horn itself. You can test it by grounding the terminal that is connected to the wire that comes through the steering column. Sometimes you may hear a faint squawk, indicating the horn is just rusty or corroded, or nothing at all. A quick fix I learned years ago is to connect an electrical jumper (wire with alligator clips at each end) to ground the horn (same thing pushing the horn ring does) and start tapping the horn body with a wooden mallet, rubber hammer, or, more realistically, whatever happens to be at hand. As you're doing this, spray WD40 into the horn and it may come alive. It's better than a 50/50 shot even if you hear nothing to begin with. If you're convinced it's the horn ring itself, get a short Phillips screwdriver and remove the two bolts holding the ring to the steering wheel. Now, it's time for surgery. First, pull on the center contact button (Ex A #7) enough to touch it to a grounded surface. The bolt of the steering wheel is perfect. Make sure to turn on the ignition. If the horn works, proceed. If not, get a replacement horn, or check the wiring to be sure everything is in order. Some models had a relay in line, so be sure the problem really is with the horn ring contacts.
The fundamental problem is with the original doughnut shaped insulator (Ex. A #4). This is a rubber-like material of questionable stability that tends to bleed and harden. It must be something about those Swedish rubber trees. It actually leaks between, and insulates the edge of the metal wafers (Ex A #3 & 5) that make the electrical contact to complete the circuit for the horn. The first line of attack is to disassemble the horn ring assembly. There are three posts on the horn bar (Ex A #1) that protrude through the contact wafers and are held together with a circlip and washer. Carefully remove the circlips and washers. I used a jewelers screwdriver to unhook them and put everything in a ziplock bag. You can tell I'm older and experienced. In my younger days I trusted my pocket or the arm of the chair I was sitting in. The two wafers will come off in one piece because they're stuck together with the Swedish rubber goop. Pry them apart and scrape out everything you see. I use a screwdriver and finished the job with a wire brush in my drill press. Steel wool or sandpaper will work, but a wire brush in a drill press or hand drill is the ticket. Buff those suckers clean to be sure of a good electrical contact. Next order of business is to liberate a mouse pad from work or your kid's desk. They're just playing games and e-mailing friends the secret moves to get to the fourth level of the second plateau of XENOTE II. While you're in their room, borrow the compass they got at the beginning of the school year and haven't bothered to use. Now you're ready to take care of business. Scribe two concentric circles on the mouse pad, one 3/4" and the other 1 & 5/16". Cut this out using scissors or a model knife. It doesn't have to be perfect; we're not taking off points for aesthetic value. Put this in one of the wafers and trim any excess from its outer perimeter. The inner clearance isn't as critical. Once you're satisfied with the fit, sandwich the two wafers together with the insulator inside and hold them together with some duct tape or equivalent. Use a 3/16" drill bit and drill through the three openings in the wafers. This will allow the three prongs from the ring to go through this assembly. You want a tight fit, so don't worry if you have to work to get the three prongs through the assembly. Reassemble everything in the reverse order in which you took it apart. Needle nose pliers work great in placing the circlips in place. By the way, I haven't mentioned the nylon insulators (Ex A #2) that are inserted in all three holes in both wafers. Needless to say, these must be in place for this "Scandinavian-Goldberg" mechanism to function properly. You should now be in business. If you find the horn too sensitive, use a thicker mouse pad material or double up on what you used. It's quite forgiving. There are probably other materials just as good if not better than the mouse pad -- use your imagination. Hope this helps you get through the weekend.
©1998 Deaver Enterprises
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