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I have a 1970 F250 3/4 Ton 2wd with, I believe, a 390. Lately I've been having intermittent electrical problems. I've traced the problem to a wire connecting to the hot side of the starter solenoid. In the attached picture it is the red wire. I replaced the quick disconnect (yellow in the picture) but that did not solve the problem. With the battery connected I can move that wire up down left right and the dome light in the cab will go on and off (with the door open of course). I have a few questions:
1. What is the black piece directly below the yellow quick disconnect? (Fusible Link?)
I think that the black thing is the juncture where the ignition, voltage regulator and alternator and possibly horn relay wires all come together to pull power from the + of the solenoid. In my opinion, that is too many wires coming together for power to be using a spade connector.
If it is a spade connector, pinch the female end to make the connection tighter, or properly splice them all together.
Hmm, I notice your Battery Positive hot cable is Black. That's Normally used for Negative ground cables. Yep LOOKS like someone done a little hack job on your wiring.
Look for loose connections at that splice red wire
Hmm, I notice your Battery Positive hot cable is Black. That's Normally used for Negative ground cables. Yep LOOKS like someone done a little hack job on your wiring.
Originally Ford used a red battery cable for positive, a black battery cable for negative, but in the late 1970's, replaced both these battery cables with blue cables.
I was really hoping this was not a hack. However, when I purchased this truck 25 years ago, it was setup for dual batteries and the owner did have some type of camper. Since this isn't a Camper Special I'd assume a local mechanic wired it accordingly.
I've removed some electrical tape to get a better picture. As you can see, a big thick black wire and a yellow wire enter the black jacket, and two red wires exit. I cannot find any information on the black jacket that would indicate it's a fusible link or what its amperage is. Looking at the wiring diagram it appears it is a fusible link. What does 38A mean? Also, is there a link to a colored wiring diagram?
I appreciate everyone's help, but I am at a complete loss.
I should also note that the reason I replaced the spade connector with another spade connector is because there was so little wire to work with coming out of the unidentified black jacket. I thought that if it really is a fusible link the heat from soldering could damage it.
I was really hoping this was not a hack. However, when I purchased this truck 25 years ago, it was setup for dual batteries and the owner did have some type of camper. Since this isn't a Camper Special I'd assume a local mechanic wired it accordingly.
I've removed some electrical tape to get a better picture. As you can see, a big thick black wire and a yellow wire enter the black jacket, and two red wires exit. I cannot find any information on the black jacket that would indicate it's a fusible link or what its amperage is. Looking at the wiring diagram it appears it is a fusible link. What does 38A mean? Also, is there a link to a colored wiring diagram?
I appreciate everyone's help, but I am at a complete loss.
"38A" is the circuit number.
Ya don't need a colored wiring diagram because it is already color coded...... Colors are represented by a one- or two-letter designation. If multi-colored, then the main color designation. For example, "BK" means black whereas "BK-R" means a black wire with a red trace.
Colors:
BK - black
BL - blue
G - green
R - red
Y - yellow
W - white
PK - pink
V - violet
O - orange
Yes, but I see very very few color designations on the 1970 links provided. Don't get me wrong. I'm happy to have it but color or color id's would be nice.
Matt
Originally Posted by HIO Silver
"38A" is the circuit number.
Ya don't need a colored wiring diagram because it is already color coded...... Colors are represented by a one- or two-letter designation. If multi-colored, then the main color designation. For example, "BK" means black whereas "BK-R" means a black wire with a red trace.
Colors:
BK - black
BL - blue
G - green
R - red
Y - yellow
W - white
PK - pink
V - violet
O - orange
