Topic: Wiring issue?

[ahavaishti]

Good Evening,

Not sure if its better suited for here or the engine section, but since I have only messed with wiring I will drop it in here.


I have a 74 formula that I recently purchased.  The man installed an electric radiator fan that did not work.  


I reran the wire, put a fuse in, and got it running.


What I noticed on the rewire was that he used the same color wire from the fan to the switch, as he did from the  distributor to the switch.

The fan was actually plugged into the fuse box, and the distributor to the fan on off switch.  So my guess is the man just got his wires crossed.  

The wire that he was using as a ground was a solid brown wire from under the dash.  Since I have rewired the fan I can not get the car to turn over.  She cranks and cranks all day.

Before I go hooking up my distributor to the brown wire, I would like to know could this jack anything up?  If so are there any quick tips to solve it.

I have a couple other issues with the car, but right now I would like to get her up and running.


I would appreciate any and all input.

Thanks

-James

[4SPEED]

the wires have to be pluged into the distributor to let it start.  well the brown or black wire does the yellow wire is the tach.

are you trying to hook it up so the fans come on with the ignition switch?

I dont think I would take the power for the fans from the distributor wiring. the fan pull to many amps and might melt some wires.  the fuse block has some unused slots, and ground the fans to the body of the car. (core support)

[ahavaishti]

I wired the fan up as follows


wire from the hot side of the battry to the fan, with a 30 amp fuse in the line.

from the other side of the fan I ran some 12 gauge wire to the switch in the cab.

Then ran some more 12 gauge wire form the other side of the switch to starter soloniod to ground the system.

I wanted it seperate for the reason that in the winter, I would want the engine bay to warm up a bit, and having that fan on 100% of the time seems like I would be working against myself.  The car also stays around 190 when im moving, so the fan would be more for around town driving.


From what I can tell the ignition is ran though a kill switch, which has 3 yellow wires hooked to it. 

I just ordered the complete restoration guide form the shop, so I am hoping when that gets here i can get the wiring under the dash straight. 

right now I have the following not working.

Speedometer
Odometer
Fuel Gauge

He ran an aftermarket tach, oil pressure and temp gauge that work.

None of them have lights except the tach.


the headlights didn't work when I bought that, but a $20 switch from autozone fixed that, however I think I have a grounding issue.  The headlights acctually dim when i twist the switch (from off, to the normal brightness).  I have never herd of a car doing that.  They go from normal to brights using the floor switch just fine.

[brian c]

Might I make a suggestion on your fan wiring?

Use a 4 or 5 pin 30A relay to power the fan as a normal toggle switch ISN'T rated for that kind of power draw. You'll burn out more switches than you can think of. You can pickup a relay at any autoparts store or Radio Shack. Probably under $6 depending on where you shop.

You can keep the toggle switch inside the car, just flip it on to engage the relay which in turn will turn your electric fan on.

[ahavaishti]

Good idea, that did not cross my mind. 

I will definatly look into that.

[brian c]

No problem.

Speedo/Odo not working - probably the speedo cable running from the gauge to the tranny. If you're running cruise control, you'll have (2) different cables - one from the speedo to the cruise transducer and one from the speedo transducer down to the tranny. Could also be the speedo gear set in the tranny itself is shot.

Fuel - could be any number of things but I'd check the grounds at the gauge pod and back at the tank. Check the wire running from the tank sending unit all the way back to the gauge to make sure it didn't get cut somewhere along the way. After that its either drop the tank to replace the sending unit OR swap the gauge to see if the gauge is bad.


And when tackling wiring problems I'd make one more suggestion....focus on one problem first. Once you get that one resolved, move onto the next. Otherwise you'll constantly be finding problems, get overwhelmed, and possibly do something you'd regret - like a hammer through the windsheild (that'd be bad).

BTW: If you don't have a multimeter, you might want to pick one up as it sounds like you'll be needing it sooner rather than later.

[ahavaishti]

Own a multimeter.

My priorities right now are:

1) getting the car working
2)speedo
3)fuel


The man i bought it from swaped the speedo cable.  So that gear is next.  i havent looked for it yet, but is it easy to get to?  Also its no cruise control.  Is that gear something i can pick up at a local auto store, or do I need to order it though sumit or jegs?

[brian c]

The speedo gears are actually 2 gears - driven and drive gears. You can more than likely pick them up at any GM dealer, Napa, Autozone, etc. I'd take the parts with you so they know what you need.

Very easy to get to. If you crawl under the car, you'll see where the speedo cable runs down to the tranny. Just unscrew it and you have access to the gears once you pop that cover off.

[brian c]

Ohh and its entirely possible the speedo itself is shot. What you can do is pull it out of the gauge cluster and spin the portion that connects to the speedo cable. If the needle moves, your speedo is more than likely working.

[ahavaishti]

I havent pulled it out yet, but when I reach under the dash i can feel a little wheel, when i twist it the needle does move.

[brian c]

So you ruled out the speedo then

My guess would be that the cable got melted and it stopped spinning. It happens. Pop under the car and see if its laying on your exhaust system. If it is, its shot and will need to be replaced. And when you replace it:

1. Grease the cable with some white lithium grease.
2. Tie it up away from the exhaust to avoid having to do this again very quickly - ask me how I know this

[ahavaishti]

how DO you know this?  /wink  bet i can take a guess.

After reading up on how the distruibior is suposed to be ran from what i can tell, the brown wire acts as the ground.  so im thinking if i reconnect the 2 I "should" be good?

or should i go ground it on the starter?

any suggestions?

[ahavaishti]

got it figured out.

since i was turning on my fan switch, and pulling out what i thought was the kill switch, the car would start

well it turns out he has the distributor hooked up to the fan switch, so when i removed that wire to rewire the fan, i took the ground for the distributor out of the circuit.

I connect the wire from the distributor to my ground and now i am golden, however I have to pull them apart since the "kill" switch is only for the lights inside the car.

Off to auto zone to buy another switch (that makes 3 now).

Going to feel like im in a space ship before long with all the switch flipping and toggling I have to do

[brian c]

What I might suggest before you do all that is just get a replacement engine harness from M&H Wiring. It'll be much simpler to troubleshoot as it uses all the factory connectors and wire colors. Once I received mine from them, I think it took about a half hour from start to finish to swap it in.

Just a suggestion. I like to keep things as simple as possible, makes it much easier to trace problems down...