Strange result after fuse block cleanup

[Guest]

While waiting for new o-rings to turn up, I've turned my attention to other things. After having issues with charging I decided to put on a digital voltage meter and in so doing found problems with the fuse block.

As I want the meter to only come on with the key on I ganged the power lead to the orange green wire. On doing that I found that while the battery was sitting at 12.5 volts the voltmeter was showing 10.5 volts. Using my portable multimeter I confirmed that that was the correct voltage on that lead. For interest, I checked voltage at the coil and found the same 10.5 v.

So thinking that the contacts in the fuse block are dirty, I dissassembled it and cleaned all the contacts to shiney metal with a points file. I even cleaned all the contacts on the fuses.

After reassembly, voltage on the installed meter and on the testing multimeter go up to about 10.7 volts.

Now to try and test that the fuse block itself is good and clean I ran a single lead from the power spade in the connector to the appropriate connector on the fuse block and I see the 12.5 volts at the fuse holders for the main 15 amp fuse and the 10 amp fuse below it, but get no readings at any of the holders for lights, turn signals or ignition. what am I missing?

With the fuse block connected to the harness connector, I get lights, signals and ignition but both the meters show the voltage at the 10.5 v.
Checking at the coils its still 10.5v, yet the engine fires. Very odd.


I'm assuming that the harness connector contacts are dirty and needing cleaning too , of course, but I just want to confirm one piece at a time.

At this point, I just want to ensure that the fuse block is clean and flowing the correct voltage but I'm not clear on how the voltage flows in and out. Could someone review that with me please?

This bike is really kicking me in the chops as it seems its one thing after another now.

Thanks again folks,
Spyug

[hjfisk]

The fuse block has to be plugged into the harness to get power to the lighting circut, unless you use a jumper wire from the main . Power goes through the main to the Ignition switch then back down to the fuse box then back to the lights. If it didn't the lights would be on all the time, just like you have power to the ignition switch all the time. Try cleaning all you connectors up, and also check the connector at the ignition switch.

[Steve]

As hjfisk mentioned, there should be a connector (or two) leading to the fuse box. One wire will be hot all the time, coming from the battery. It then goes through the main fuse to the ignition switch via a red wire. It returns from the switch on an orange wire to feed the other three fuses that feed the rest of the bike.

My suggestion would be to compare voltages at the following locations:
1. battery (reference point)
2. 'hot' side of main fuse (checks for loss in the main feed)
3. 'dead' side of main fuse (checks for bad connections in the fuse holder)
4. 'hot' side of [light, signal, ingition'] fuse (checks for loss in the run to the ignition switch)
5. 'dead side of [light, signal, ingition'] fuse (checks for bad connections in the fuse holder)

My guess is that you are losing most, if not all, of your voltage drop in the run to the ignition switch.

Two solutions to this situation.
1. Clean all the connections between the fuse box and the ignition switch AND the contacts in the switch itself
2. Install a relay to feed the fuse box. The relay would be switched by the orange wire that is now feeding the fuse box, so if it still has a slightly lower voltage, it won't really matter. Note that this solution will also require re-routing the output wire from the R/R, as it feeds the line going to the ignition switch, which now would only be used to turn on the relay, it won't do anything to run the bike or charge the battery.

On the bikes that I have on which I have installed a new Eastern Beaver fuse box, I have used solution #2.

.

[spyug]

Thanks for the replies guys. Helpful as always.

I had been thinking that my next job would be to clean up all the connectors downstream from the fuse block, in addition to wiring in relays as suggested. I'm pretty certain now that the fuse block is squeeky clean so its got to be down to the harness wiring and connectors. Hopefully I can get the connectors out of the plastic block without damage. That always seems to be a difficult job.

I'll let you know how it turns out.

Cheers,
Spyug

[rustybronco]

Pay careful attention to the connector just off the ignition switch. The one on the 80 was melted.

[Nessism]

Once you get the hang of removing the terminals from the plastic connector shell the clean up job goes pretty fast. A terminal tool really helps with this task. I used some diluted HCl to clean the terminals on my fuse block, along with scrubbing with a stainless steel brush. You should also pinch down all the female terminals so they fit tightly together with their mate. I did this with my own fuse block and picked up 1/2 volt on the charging voltage. Wish I had done this on my enter harness during the rebuild but oh well.

[Wizard]

When ever I work on an electrical issue, I never leave the area without Soldering the Connectors.
All those connectors are just crimped, copper wire in aluminum connector or some terminal electroplating.
The 2 different metals alone can create Galvonic Corrosion.
Over 25 years the wire/connector junction can go resistive.
Add current and it can also get hot.
Use a Soldering Iron, some flux and Resin Core Solder.
If the connecter is quite dirty you may have to use Acid Core Solder, but you need to wash it clean after (Throttle Body Spray will do).
Fixed a few odd problems like that, never came back.
Your Fuse Block is probably fine.
I have had the odd fuse that "looked" good, metered fine, but went Open under Load. Bad fuses happen.
Meter right across the fuse with power ON, should be Zero Volts.
If you don't have Soldering Iron stuff, you should.
My Industrial Electronics background Cringes at the stuff I see in Consumer Land,,..

[spyug]

Well I followed the sage advice offered and found my problem is in the right hand control so the "kill" switch or starter button.

After cleaning up all the connectors I'm done in for tonight but will get that sorted tomorrow. Once I had more or less 12+ volts running around again I will fire it up and see if that had any bearing on my dieing idle. If not, the o-ring s came in from Mr. Barr today so the carbs will get redone as well.

With a bit of luck I may even be riding again by the weekend.

Here's hoping,

Thanks for all the help folks.

Spyug

[kdo58]

mine started dying at stop lights, the connector coming off the ignition switch was melted.