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Various Electrical Questions and Issues

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fleshy1

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The Prince (not to be confused with His Purpleness) struck last night on CA 134 just before Victory Blvd. in the number 2 lane. Nothing like watching every car have a close run in with your bumper.

I'm confident that the trouble was on the white circuit since the starter was cranking well, but I had no ignition light. I tried getting spark and there was none and the fuel filter looked empty (I like those clear ones). After jiggling the brown yellow at the alternator, fuel pump connection, and white connections at the fuse box it fired and I was on my way.

So here are some questions:
1) Upon removing the fuel pump cover I noted the white wire, but also found a black wire with a blue blob on it connected to the terminal (using a dual male connector.) I do not see this on the wiring diagram. I removed it because I managed to break off the male spade for the white wire. The pump seems to function without it is there a need to find another dual male connector?

2) I've been getting the dull glow at night when running the heater fan or using the blinkers. Time for a new alternator? Is there any reason that I should spring for the Saturn upgrade?

3) What gauge wire should be used? I have some ugly looking connections that I feel should be addressed and don't have the money to do a harness replacement.

4) What are the best methods of cleaning electrical connections? Emory paper, erasers, spray cleaner?

Thanks for your help!
 
Where does the blue wire go? Does it ground to earth?

I clean connectors with emery cloth and then coat in dielectric grease. Seems to last years that way.
 
The black wire with blue blob appeared to be hanging free under the pump cover but could easily have gone to earth by slipping the forked terminal under one of the cover screws.

(Guess it's Emery and not Emory :p )
 
It appears that I'm grounding through some other method. The black and white are on the same terminal so I'm guessing that the blue blob is a diode to allow the pump to ground (when the points open) and not short back.
 
Eric - The "blue blob" is a capacitor for radio interference suppression. One end should go to the power terminal of the pump and the other end to ground. I suspect that the problem you are having is bad connections. there are small wire brushes available that are really great for cleaning connections. You should get one of those, disconnect your battery and start cleaning connections in the wiring. You can use a small caliber gun cleaning brush to clean the female bullet connectors. Once cleaned, coat each connector with dielectric grease as Steve sugests and reassemble. It doesn't hurt to put a blob of dielectric grease around the wire wfter inserting the male bullet into the female connector to geek any moisture out. The fact that you were able to get under way again simply by jiggeling some wires tells me that you definitely have connection problems.
Cheers,
 
Put the dielectric grease on the bullet connectors before plugging them in.

Replacement connectors are available at https://www.britishwiring.com For less than $20- you will be able to get a variety of bullet connectors and sleeves. They will be able to help you with replacement wire too.

Below is a link on how to attach bullet connectors to wire.
https://www.advanceautowire.com/headlight.pdf

For an alternator, there are a couple of options, the Bosch unit which is suppose to use the same plug as the Lucas and can be had locally with a lifetime warranty for less than $60-, or the Saturn/Delco, also available locally, which has a higher output and you would have to install a connector for it.

Use a wiring diagram to keep track of the connections as you service them.
 
Thanks Kim.

I just went out to start the beast and I've got the same problem. That started this thread. I'm at work so I don't have a voltmeter. Here is what I found:


1) Horn, headlammps, interior light working (power to the purple circuit)
2) Turn the key to run position (just before the start). I can hear there fuel pump so there is fuel. Ignition light does not illuminate. I have no power on the green circuit (wiper motor). This means no power to the White/Brown.
3) Turn the key to start and the starter turns. No fire from the coil.

It's a 1978 so it has the ignition relay and thus I'm guessing the relay isn't closing the circuit to the ignition lamp thus allowing power to the white/brown and green.

Is it possible to wire each side of the relay together to get home? I've got some wire and butt connectors with me.
 
Well I got it going again by messing with ignition relay. Then I got half way home and it died again. More jiggling and I got off the highway and jumpered the high current side of the relay to get home.

I went to two auto parts stores and found that they had nothing! Not even generic stuff on the floor. I decided to try Radio Shack and I'm glad I did. The salesperson had it in my hands in less than a minute at only $6.

I'd really like to put an original Lucas relay back in, but the last one's build quality was quite poor compared to the new one.

It seems that my idle is much more even now.
 
I think Moss motors has the original style relay for around $40-. You should be able to get a bosch one for less than $15- at autoparts stores such as Napa. Many people have used the generic one like what you purchased without any trouble. Your experience when trying to get a replacement relay from an autoparts store makes me wonder if you got an inexperienced counterperson. Need to find out why the ignition light is not working, some alternators will not charge if the bulb is disconnected or burnt.
 
Kimberly,

The ignition light works now that I've replaced the ignition relay. The low load side of the relay completes the circuit for the light (brown/yellow - warning lamp - white - inertia sw - white - ignition sw - white - ignition relay - gnd)

I went to two parts stores, both large chains. No one can find anything without the vehicle information. The one small shop I tried was burnt down!

Still getting a faint glow when I switch on the heater fan. I'm going to try getting the multi pin plug apart so I can clean connection.

Unfortunately the Bosch Alternators are now $100. There are cheaper ones that fit a Fiesta, but they are not of the same case design as the Bosch.
 
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