It's the little things that do it to him

Small things
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Our engines and cars have a past. That is precisely the charm. We therefore carry out loving maintenance and we restore. But we usually forget a very important chapter. And then the problems begin. The problems with 'our electrical system'.

The most authentic connections are those where picks have been used. For example, the voltage regulator, the ignition coil (s) and instruments then have wire ends of usually 4-5 millimeters. Just a finger of acid-free Vaseline along. The relevant plug eye over it. Eating ring on it. Nut on it. Ready. But not for thirty or forty years.

From the XNUMXs, the industry began to work with sliding plugs. The best idea came from AMP Incorperated, now part of the Tyco group. The now famous 'males' and 'females' with their color codes for the wire sizes plus amperages and in a variety of designs became the norm until wiring became so complicated that manufacturers switched to using multi connector blocks. Now they are mainly used by 'us' hobby riders.

The AMP cuttings did well. But the longer they were in a fairly humid room, the oxide between the connections. These oxides provide transitional resistances, heat development instead of electrical contact. The visible results are greenish-turned connections and possibly hardening, or the melting of the insulation, by heating due to the transition resistance. In lighter cases, it is sufficient to shower the connection with an aerosol contact spray and to release the connection a few times and then re-light it. If the matter is really oxidized, then we have to go a step further. Because often the problems are in the connection between the wire and the plug. By oxidation of the solder connection or the terminal connection. Then it really only helps to short the plug to replace it with a new one.

It is best to switch on a new plug by soldering it. Do that with a soldering iron that delivers so much power that the soldering action is as short as possible. In this way, heating of too large a part of the cable - and thus the thermal load on the insulation - is avoided as much as possible. Use acid-free soldering fluid for soldering. Grease the new compound with acid-free Vaseline.

The second best way is therefore used the most. That is a choice of responsible laziness The AMP slide plugs are offered at all fairs and at every hardware store. We will leave the specimens from the famous 'buckets'. They are made of inferior material.

The plugs are clamped around the stripped wire end with the professional pliers supplied in a 'beginners set' or purchased later. This may have been done somewhere in the past of our vehicle by squeezing the plug over the stripped copper core with a pipe wrench. Maybe even about a copper core that was not sufficiently brightened. And that is why we are now in trouble. The loose copper wires that make up a cable have been unprotected for years. For self-protection, each individual thread has put on a greenish oxide coat. And all that oxide has an insulating effect. Does not transmit power. Generates heat.

Also take a look at the wire that is plugged in. It is best to use cable with as many loose copper wires as possible. It is flexible and the most trouble-free. With repairs and hobby work you can come across everything from a massive copper core from the residential or industrial wiring to modern wiring with a limited number of copper wires.

AMP plugs can form a good connection, but then a few preconditions are needed. First, the wire must be stripped over a sufficient length. The AMP plugs with a red indication must be made free of insulation over a length of 5 mm. The blue AMP plugs that are more common with us must be stripped over 6 mm.

Give the newly stripped copper cores a lick of acid-free Vaseline and slide the AMP plug over the bare wire. Tulip the pierced end out with an awl and give it an extra lick of acid-free Vaseline. Then squeeze the connection with the corresponding colored jaws of the AMP forceps. Then squeeze the plastic overlap of the red or yellow insulation sleeve around the insulation of the wire.

Also make sure that such connections are 'draining', that descending (condensed) water flows through the female to the male and then back to the wiring.

Then spraying with a moisture expeller will not hurt. According to some experts, only the use of the famous WD40 is out of the question because its secret components would be diesel and phosphoric acid. That phosphoric acid is again damaging to the plugs.

A multitude of problems due to mass connections

However, many of our problems are due to a blocked drain, rather than a faltering supply. We are talking about mass problems. And that return line is important for the cycle.

The problems are the places where there are metal to metal connections. Or should sit. Between instrument holders and their confirmation. Between engine and chassis parts. Problems like that are nice to solve. They can often be found by drawing an external ground connection with a long piece of wire between, for example, a non-functioning rear light and the ground of the battery. That eliminates all further possibilities or difficulties. There is woven mass wire for sale at the automotive parts trade. Often complete to length with soldered eyes. If such a cable is laid 'grounded' from the refusing part, make sure that there is a clear metallic connection and also use the jar of acid-free Vaseline. For the motorcyclists among us: it is very important that the steering head and front fork make mass. The connection between them is formed by a bed of grease-bearing ball bearings plus the counter cables. It is surprising how many inexplicable problems disappear when a ground connection is made between the fork and the frame.

But sometimes we continue to have inexplicable failures. Then only one thing helps: measuring by cable in the wire harness. Because even the neatly taped-in or shrink-wrapped part of that cable harness can have malheur. For example, there may be wire breaks in seemingly perfect pieces of wiring. And what has happened more than once: over the years, soldered connections in the cable harness can harden or even decompose chemically. That is why it is useful to do soldering work with an acid-free soldering liquid.

Because even the most careful restoration can come to a halt due to a loose connection in 'the electrical system'.

Some cable diameters and their maximum allowable amperage
0,65mm2, max. 5 Amp., For, for example, relay control

2 mm2, max. 17-18 Amp. For, for example, headlights

6 mm2 - 7 mm2, 40-50 Amp. For the dynamo, for example

23mm2, 60 Amp, for the starter motor

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  1. NEVER, but NEVER use solder water for electrical connections. this actually promotes oxidation. use tin solder 60-40 with a resin core, that's really something else you use for the water pipe !!! if the solder doesn't "pick up" or flow nicely, it is not hot enough or the surface is oxidized. make sure that what you have soldered is not exposed to vibrations, mechanical loads or high temperatures, then the connection will simply break off over time.

    better still are crimp connections, but without vaseline mounting. you only do that after assembly, otherwise you make an insulation instead of a contact surface. on the contrary, you must ensure that you get as much white copper as possible against each other.

    I have been an installer on ships and agricultural vehicles. I do my own vintage car in the above way and never have electrical problems !!

  2. There is sometimes discussion about WD40. One says that you should spray it on the connection between your spark plug cables and spark plugs and under your distributor cap, because it would be moisture-resistant, the other says you should never do that, because it eats away and damages the gear.

  3. And a valuable addition: don't forget your fuse box when it comes to electrical malheur ..
    Many (sticky) old 6Volts bicycles (such as a WLA) often do not even have a fuse, so place at least one to prevent the cable harness from breaking out due to a short circuit.

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