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rjc157

rjc157

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Been having trouble getting my rebuilt tach to work properly was told it could be the switch so I bought a nos switch for my bj8 negative ground it was converted yrs ago now trying to retrace steps in the back of the switch there are only 2 spade connectors at the #2 post and I have 3 connectors I know one is the fuel pump one goes to the fuse box and the third one is supposed to run through the loop to the dist what do I gang together .From what I see on the wiring diagram the fuel pump is not connected to the switch what do I see that's wrong ,I know this is stupid but on a neg ground car doesn't the switch wire go to the positive side of the coil and then there is a wire going from the neg side of the coil to the dist hope this makes some sense its driving me crazy
 
rjc157 said:
Been having trouble getting my rebuilt tach to work properly was told it could be the switch so I bought a nos switch for my bj8 negative ground it was converted yrs ago now trying to retrace steps in the back of the switch there are only 2 spade connectors at the #2 post and I have 3 connectors I know one is the fuel pump one goes to the fuse box and the third one is supposed to run through the loop to the dist what do I gang together .From what I see on the wiring diagram the fuel pump is not connected to the switch what do I see that's wrong ,I know this is stupid but on a neg ground car doesn't the switch wire go to the positive side of the coil and then there is a wire going from the neg side of the coil to the dist hope this makes some sense its driving me crazy
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The wiring of the car for Neg Ground Or Pos ground is the same . The only difference is the connections on the battery and the way the tach is wired INTERNALLY , that's it that's all .
So if you had a neg ground tach and a pos ground tach all you have to do is put the appropriate tach in with the battery connected correctly for that tach and it will work . no wiring changes needed at all .
 
Hi Ralph,

It is always difficult trying to identify the motivation behind past changes and, even when I make the changes, need to document the change and reason or risk being lost. An example of this happened when installing relays covering my headlights and driving lights, I was surprised to discover an in-line fuse I could have installed in the '80s.

As you mentioned, the fuel pump should not be connected directly to the ignition switch but the other end of the wire at the fuse box. There is no difference except the availability of a convenient connector. The line going to the distributor from the coil is now either marked "SW" or "-" at the coil. If I read your post correctly, I believe you have all OK with the ignition line connected through the tachometer loop (now looped in the opposite direction from original) and connected to the "CB" or "+" side of the coil.

I frustration is understandable.

Good luck,
Ray (64BJ8P1)
 
Two of the white wires are ganged into one female spade connector on my harness. The three white wires are:
1) Fuse block
2) coil (looped in back of tach.)
3) Ignition light on tach.
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Hi rj, The fuel pump wire in the original electrical plan is unfused. It is attached at the fuse block but on the same terminal as the hot wire feeding that fuse. Which is the hot side of the top fuse. On the other end of that top fuse there should be 5 green wires. They are going to other parts of the car such as an example being the wiper motor. They are fused by that top fuse. On the source side of the top fuse should be 3 white wires. One white is the power coming to that point from the ignition switch, one white should be the fuel pump, and one white is going to the Overdrive relay. There should then be a white wire coming from your ignition switch to the loop of the tach then going on to the (+) terminal of the coil. Cheers Dave.
 
Just went back to the switch I had in it before don't know how the fuel pump wire got there but it is
 
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