Voltage loss at coil when headlights are on 6 Volt System

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The voltage at coil drops to 5 volts when headlights are on my 62 bus with 6 volt system. The bus slows/power loss when driving with lights on. Checked generator and it's working. Traced back to fuse box also losing power when the lights are on. The red dash light goes on and gets brighter when I accelerate also with lights on. Any ideas?
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62 Samba
67 Double Cab
52 (September) Split Beetle Deluxe Ragtop Azure Blue

[Braukuche]

[[email protected]]

Yes, with hot wire off the regulator, the voltage at RPM goes to 8. I just switched out the voltage regulator. The voltage at the coil is better but still under 6. It appears that I am losing approximately 1/2 volt from power to fuse box (fuse #1) to fuse from the ignition switch (Fuse #2). When its running at higher RPM and lights are on, 6.4 volts at regulator, 6V at fuse box main power fuse (fuse #1), 5.5V at fuse #2 (power from ignition switch) then roughly 5.2V at the coil.

Should the voltage drop that much through ignition switch and from fuse #2 and then to the coil? I just had ignition switch rebuild less than a year ago. Grounding issue or ignition switch or? Thoughts?
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62 Samba
67 Double Cab
52 (September) Split Beetle Deluxe Ragtop Azure Blue

[Eric&Barb]

All the electrical power runs thru the headlight switch before going to the fuse box. Do not use headlights with much more amperage than the original 50/55 Watt bulbs. We are running 55/60 Watt H-4s and to do that required cleaning up the wiring, and soldering the internal connections of the headlight switch and fuse box. Without that wiring work some of the wires at the headlight switch started to blister and the far right fuse box fuse was so hot you could burn fingers on with the headlights on. The fuse box started to melt due to the fuse over heating from the loose oxidized electrical tabs in the fuse box.

http://www.thesamba.com/vw/forum/viewtopic.php?t=483901&highlight=fuse+box+soldering

http://www.type2.com/library/electris/vw-hauptlicht-schalter.html

Electrical tabs on the ignition switch can be soldered to the posts that hold them to the switch for that more less voltage drops.

Also get the Wolfsburg West battery cables. They are made just like the original factory ones, and will last several times longer than any FLAPS ones you can get. Just do not over tighten the clamps onto the battery terminals.
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In Stereo, Where Available!

[[email protected]]

Thank you for the input, Eric&Barb. I switched out the ignition switch from my Double Cab and same voltage loss of 1/2 volt and same issue. The wiring loom was replaced about 20 years ago when the bus was restored. I will clean up contacts and look at the soldering the fuse box. I definitely think it's something to do with the lights. I did find another issue, not sure if related. The wire for the blinker light on the dash was not connected to the flasher relay and the end was taped off. I was wondering why the light never came on when using the turn signals. When I attached it to 49a on the flasher relay, the light on the dash stayed on even without indicators switch on. When I flip the indicator on the lights on the dash blink properly with the indicator lights outside. Another issue or maybe related?
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62 Samba
67 Double Cab
52 (September) Split Beetle Deluxe Ragtop Azure Blue

[Eric&Barb]

[[email protected]]

It does have an original e flasher relay and it works.
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62 Samba
67 Double Cab
52 (September) Split Beetle Deluxe Ragtop Azure Blue

[Eric&Barb]

[[email protected]]

I'll have to try the homemade relay deal then after I fix the voltage loss issue. They don't make a repro 4 pin e relay. I read somewhere about a diode you put on the wire so no back current or something. Thanks again.
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62 Samba
67 Double Cab
52 (September) Split Beetle Deluxe Ragtop Azure Blue

[telford dorr]

Basically, you have to take every connection from the battery to the headlight switch apart, clean it, buff it, and reassemble. Don't forget the ground cables. The problem with copper and brass connections is that they corrode over time. Soaking in weak acid (white vinegar) works well for removing corrosion, along with Dremel tool rotary wire wheels.

The problem with 6 volt electrical systems is that any device, to develop the same amount of power, draws twice the current that a 12 volt device would. Twice the current causes twice the power loss from a poor connection, thus 6 volt systems are much more sensitive to connection integrity.
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'71 panel, now with FI
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More VW electrical at http://telforddorr.com/ (available 9am to 9pm PST)

[Eric&Barb]

[[email protected]]

So I took out the fuse box and soaked in the white vinegar then brushed it clean. I soldered the plates and put her back together. No more red light, no power loss. I drove her 56 miles today. Thank you all for the help. Now on to the signal dash light issue.
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62 Samba
67 Double Cab
52 (September) Split Beetle Deluxe Ragtop Azure Blue

[ToolBox]

[Eric&Barb]