bronco gauge help needed

[unibody madness]

The turk is fired up, the hydraulic clutch is up and running, hope to have a brake problem solved by wed.

Sooooo..... I noticed that both the temp and oil pressure gauges peg out soon after starting the ol' 292. I thought I bought the correct sending units but it was evil bay after all.
I just had the wiring harness/ dash insert, hanging in the engine bay for start up, so maybe no ground?
Does it sound like sending unit problems, do I need a special voltage regulator under the dash?
I used the regulator that came with the bronco dash and then tried it with one from an original dash insert.
If anyone who has done this upgrade has any insight I would sure appreciate some help.
John

[Toyz]

Needs to be grounded, John.
Paul

[aeromech]

I'm no electrician but I had an instrument transformer short out and that drove all electrical instruments to full scale. My understanding is that it is a sort of make and break unit that essentially reduces 12 volt to around 9 volts to power the sending units. I have an early Bronco and 2 '65 pickups and the instrument transformers look to be identical. Later models have different connectors. As I said, I'm not much of and electrician, more of a parts changer but replacing the instrument transformer fixed my problem.

[Toyz]

John, you stated "soon after" starting. Did the gauges peg when power was first supplied to the instrument panel? Next question is ,are you applying power to the input side of the i.p. regulator? This would be the side opposite the terminal feeding the gauges. You may want to jump the i.p. regulator case directly to ground, or at least make sure the regulator is secured to the panel. Having swapped out the regulators, gut feeling is just as you stated; the regulator is simply not grounded.
Paul

[bobenhotep]

I ran a separate panel ground just to avoid stuff like this. 9 times out of 10 if you have an electrical problem that defies logic you have a ground fault.

[unibody madness]

Thanks guys, I just got home from a weekend away, I will try grounding the unit tommorow. I got the feeling it might be the ground, which is why I added it in my first post.
I'll check in when I know for sure

[ThinLizzy13]

Do the round bronco speedos interchange with round truck ones without changing anything?

[unibody madness]

You have to swap sending units to the gauge ones rather than the idiot light units. But the the dash inserts from the bronco and some of the larger trucks will swap right in.


Paul, the gauges peg as soon as the power is turned on. I will run a ground wire to it in the next few days. The transformer is side specific with a male and female lug, I hooked it up as built. I am hoping its a ground problem.
John

[unibody madness]

Started to hook up the dash today, All the guages I hooked up worked fine when the insert was grounded. Thanks for all the help