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I'm interested to hear what you find out about the oil gauge.......mine does the exact same thing. Good CVR, new gauge sender and NOS oil gauge. I'm stumped.
I'm thinking bad sender as well, with the key on, engine not running the gauge doesn't move. That makes me think the sender is grounding out internally?
Wish I could remember how I did mine without pulling out the dash to look behind. When I put the gauge in I used the adapter that can hold two sending units. Put in the original one for the idiot light and one for the gauge. Had the harness, with the white/red wire, from when I got the amp harness. Opened up the back plugged it in, connected the amp wires,added a lighting wire for amp and oil then started the truck. All was working from that point on.
Actually I opened it two weeks ago looking to find a place for lighting two extra gauges below the dash and found an open female plug for the lights. Worked perfectly but that was 2 weeks ago before this thread.
After searching automotive forums I found a test procedure for the oil pressure sending unit. Upon performing this test, both of the oil pressure gauges I have responded exactly the same was--went from pegged "high" with the wire connected to the sending unit to being at the lowest point upon disconnecting the sending unit wire. Also, the gauges pegged high when the sending unit wire was rounded to the engine block. So in my case, it appears my NEW sending unit is BAD.
So here is the test procedure:
1.Test the gauge by grounding the wire that leads to the sending unit on the block.
2. When the wire is disconnected from the sending unit with the key switch on, the needle on the oil pressure gauge should be either all the way high or all the way low.
3. Grounding the wire should make the needle move to the opposite side of the gauge from where it was before the wire was grounded.
4. If the vehicle is equipped with an oil pressure light, touching the wire to ground and then removing the wire from ground should turn the light on and off.
5. If either happens, the gauge and wiring are good and the sending unit is faulty
Originally Posted by johnmel59
OK, update for today.
1. Replaced the ground wire from the gauge cluster to the truck with a heavier gauge wire.
2. Checked the Red/White wire from the sending unit to the gauge -- good continuity, no response on the test light so its not "hot".
3. Checked the Black/Green wire using a test light it is "hot".
4. Exchanged the Gauge Constant Voltage Unit with the one from my previous dash cluster -- I know this one was good.
** Still the "Bronco" oil pressure gauge pegged out high again **
5. Attached another oil pressure gauge to the dash wiring and it also pegged out high! **
So, the only thing let that I can think of is the new sending unit is "bad". Is there a test I can do for the sending unit?
Does anyone have any other suggestions?
Thanks in advance!!! John
P.S. -- on a side note, the new "alternator" gauge is working great -- as are the "fuel" and "temperature" gauges!!!
OK, so I have the 70 amp circuit breaker pictured below. Can someone give me some advise on the best way to mount this breaker on the inner fender? Also, confirm where in the wiring system does this breaker go.
Looking at the wiring diagram it appears the 8 gauge wire runs from the solenoid to the breaker from the breaker to the alt gauge and them back to the junction post with the yellow/black alt wires. Is that correct?
Thanks
in advance! John
Originally Posted by The Masked Rider
Don't forget there is a 70 amp Circuit Breaker that is located somewhere next to the starter relay/solenoid on the inner fender skirt. Its round.
That black/yellow wire should come from the relay, to the circuit breaker, than loop through the ammeter and back to the junction block. Somewhere after it passes through the ammeter, there should be a 'T' wire spliced into it and run that over to that lower pole on the ignition. I'm also going by memory here, SO...
John is correct on all of it, just forgot the Circuit Breaker. Means a lot should you accidently ground out the power on that wire. That would not be fun.
There is a great book you might be able to find on-line or ebay The book is called '1965- 66 Ford Truck F-100 Wiring Diagram Manual'. I think that's the name of it. Its a 8 or 10 page hard paper booklet. I believe it was put out by Jim Osborn Reproductions. I can go dig up the book if you need info on it. Or just surffffff.
By the way, I did have to replace that wire on one of my trucks and it measured out to be #6 I believe. Big wire.
11-23-2014, 04:25 PM
