Any Auto Electricians on board? 67 Fairlane charging issue.

[66FAIRLANE]

This is a weird one. Story so far. Still has factory alternator and regulator. My factory ammeter (Aussie dash) started behaving badly. It basically turned into a tacho. Zero at idle and more charge as you revved. Never going near zero while driving (revving) except at idle. So, I took the regulator apart and found it looked pretty good but with small burning of contacts. I cleaned up the contacts with fine wet and dry and reinstalled. Fine, all normal again.

In my experience however I have found that once you clean contacts in this manner it is but a short term solution so I ordered what I hoped was the right regulator from Autokrafters. It arrived last week. Looks exactly like the one on there. Black cover. I installed it yesterday and all looked fine. Ammeter doing what it should. Then I went for a drive. At higher speeds (above around 50mph) the ammeter started rapidly flicking between just above zero and half charge. Backed off throttle and it settled to normal. Into throttle again and it repeats the flicking. Hmmmm, rpm related I thinks. Get back home in the garage, put car in neutral and rev. Nothing. Fine. Put in drive and rev up against the converter and the flicking begins!

WTF? Any ideas?

[ScotiaFE]

Yup.
Disconnect the ammeter.
Install a voltage meter. 

[machoneman]

Check your grounds (w/OEM Ford, intake manifold to firewall) and the sheetmetal area directly under the voltage regulator. Closely inspect your battery cables at both ends. Do some dash diving and double check all under-the-dash connections and that no bare wires are rubbing.   

[66FAIRLANE]

Yup.
Disconnect the ammeter.
Install a voltage meter. 

Yeh that makes sense. As with all my cars if its fitted it must be working.

No out of place gauges in this car. I know it can never be original but I want it looking as original as a RHD converted LHD car can be. 

[66FAIRLANE]

Check your grounds (w/OEM Ford, intake manifold to firewall) and the sheetmetal area directly under the voltage regulator. Closely inspect your battery cables at both ends. Do some dash diving and double check all under-the-dash connections and that no bare wires are rubbing.

Thanks Machoneman. Will do although all the grounds at the regulator are good and I have a large engine to chassis ground strap. Battery terminals are clean and tight. Its just a real weird one. I will swap the repaired regulator back and see if it returns to normal. I will open up the new one and see whats in there. Maybe its solid state and don't work real well with an old alternator? Maybe the alternator has some suspect output and the new reg is too sensitive? As I said, works fine until the road speed increases. Fark knows.

[My427stang]

I'd start by bypassing the regulator, make a jumper wire that will connect 12V fto the field wire at the VR plug.

See what it does for voltage then, it should immediate climb and slowly continue to climb past 15V, if it is not repeatable as you unhook it and hook it back up, I'd be checking grounds, if it's intermittent like a switch, I'd guess a field problem in the alternator.

If it charges well when jumped, you could just have a second bad regulator

[66FAIRLANE]

Thanks Ross. Will give it a go. Put the old regulator back on today and all seemed fine. Opened the new one and it has two coils in it like the old one. Just underneath it doesn't have as many as those weird looking coily things.

Couple of pics for the hell of it.