Ammeter wiring question

drbill

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I've been reading some threads on the Tiger email list about wiring an ammeter properly. From what I gather, it looks like the heavy gauge wire from the starter solenoid is disconnected from the voltage regulator and run to one side of the ammeter. Another wire is then run from the other side of the ammeter back to the voltage regulator. Is this correct?
Thanks,
Bill
 
Bill,

My answer is yes, but am saying so in the context of a generator system. You can confirm the wiring using the wiring diagram in your shop manual. Be sure you have the correct "heavy wire" and "regulator terminal". The wires are color coded at least if they are still the factory wires. The factory wire from the solenoid is brown and the correct regulator terminal is the B or BAT one. You did not say which terminal you were considering in your question.

As you are installing your new dash, I have a couple of unsolicited observations I hope you will not mind.

If your existing oil pressure gauge line is at all old or seems stiff, now is the time to replace it with a new one. The engine heat and years can take a toll. One of the things you never want to happen is for that line to break while you are on the road. There goes your engine oil pressure and a huge mess and no easy fix.

If you are installing a new ammeter, don't forget that the instrument grounds are all daisy chained from one to the other by black wires under an instrument mounting nut. Your new ammeter will need to join that chain.

Sorry if this is stuff you already know, at least I feel better by mentioning it.:)

Gene
 
Bill,

My answer is yes, but am saying so in the context of a generator system. You can confirm the wiring using the wiring diagram in your shop manual. Be sure you have the correct "heavy wire" and "regulator terminal". The wires are color coded at least if they are still the factory wires. The factory wire from the solenoid is brown and the correct regulator terminal is the B or BAT one. You did not say which terminal you were considering in your question.

As you are installing your new dash, I have a couple of unsolicited observations I hope you will not mind.

If your existing oil pressure gauge line is at all old or seems stiff, now is the time to replace it with a new one. The engine heat and years can take a toll. One of the things you never want to happen is for that line to break while you are on the road. There goes your engine oil pressure and a huge mess and no easy fix.

If you are installing a new ammeter, don't forget that the instrument grounds are all daisy chained from one to the other by black wires under an instrument mounting nut. Your new ammeter will need to join that chain.

Sorry if this is stuff you already know, at least I feel better by mentioning it.:)

Gene
Thanks, Gene. The brown wires on mine have been replaced with yellow and the yellow with red. The gauge on the wires is fine, but at some point, factory wires were replaced. I have identified the B terminal.
I have replaced the oil pressure line. I had the same thought about it giving out while on the road. Not a fun prospect!
Speaking of ground wires, i guess a clock would be grounded the same way. I bought one from The Gauge Shop in the UK, but in testing it, it doesn't seem to work. I put a live wire on the lug and tried to ground it via one of the mounting screws, but no joy. The guys there said it had been gone through and tested. Oh well.
I just keep telling myself, "Wiring is fun, wiring is fun....." :rolleyes:
 
Bill, yes you are right about the clock ground. Surprised something from the Gauge Shop does not work. The clock is a negative ground clock right? Or has been upgraded to be polarity neutral?

Did you adjust the hands at all after the hookup? Pushing that reset knob/shaft down on the Smiths clocks is sometimes necessary to start the clock if it has been disconnected.

Gene
 
Bill, yes you are right about the clock ground. Surprised something from the Gauge Shop does not work. The clock is a negative ground clock right? Or has been upgraded to be polarity neutral?

Did you adjust the hands at all after the hookup? Pushing that reset knob/shaft down on the Smiths clocks is sometimes necessary to start the clock if it has been disconnected.

Gene

Hmmm, not sure about polarity neutral... I assume it's a neg ground. I need to shoot them an email.:confused:
 
Some More Guidance

Bill

I installed my ammeter about 2 years ago. Tiger Tom Erhart walked me through it. Automotive electronics are far from my forte...but I can honestly say his guidance was spot on and invaluable. My ammeter is working fine and I did not burn my Tiger into a cinder doing it. Below is the guidance he provided me.

Here's the theory. All electrical current, except starter, goes through the ammeter. Period. It's that simple.

Here's your mission. (assumes previous owners left original wires in place).
1. Find the big brown wire on starter solenoid that goes to voltage regulator.
2. Disconnect big brown wire from VR, splice a10 gauge wire to that wire and run to the ammeter.
3. Connect a 10 gauge wire to ammeter and connect to VR terminal where other wire was removed.

It's that simple. Now some details.
* Properly tin and solder all connections, and especially terminals. Unless you have an AMP terminal it is likely junk. When installing a terminal on the wire, remove the plastic insulation crimp first. Slide about 1 1/2 inch long shrink wrap over the wire, solder the wire in the terminal and then slide the shrink wrap over the soldered area and shrink. Do not deviate. .

* Your ammeter is certainly the correct type but I can see that at one time it was over heated a bit. Probably not to failure. I'm fairy certain it will be OK. The needle should pivot on bottom when mounted in dash and show 30 AMPS.

* Ammeter connections are critical. Originally they used the "FASTON" type blade connectors, which contributed to the overheating issue. You queried about spade or ring tongue. Ring tongue is the only way to go. A spade will spread and work loose.

* This following are critical steps.
1. There should be two 10-32 nuts on each post. The first one should secure the tabs and post. Make sure they are very tight and snug. Can't give you torque figures, but common sense with experience plays an important part here.
2. Install ring terminals, then a flat washer (brass preferred), a star type lock washer then the nut.
3. While holding first nut, tighten nut that clamps spade terminal.

* I can't remember which wire goes on which post. To determine, simply attach the wires loosely and turn headlights on. Gauge should swing to discharge side. If not reverse wires.

Finally, remember, your entire cars electrical system (except starter current) goes through these connections. Do it right. Secure everything. If bending wires near ammeter, hold the terminal and bend the wire. Do not hold the ammeter and bend the wire. The ammeter itself should not feel the mechanical stress of wire bending.



Jim
 
your entire cars electrical system (except starter current) goes through these connections. Do it right.

Thats why I have a volt meter. You want unfused large gauge, high amp wires exposed in the passenger compartment after a wreck? Why risk it???????????

Plan for the worst, hope for the best.
 
Bill, yes you are right about the clock ground. Surprised something from the Gauge Shop does not work. The clock is a negative ground clock right? Or has been upgraded to be polarity neutral?

Did you adjust the hands at all after the hookup? Pushing that reset knob/shaft down on the Smiths clocks is sometimes necessary to start the clock if it has been disconnected.

Gene

Gene, You are a genius. It was simply a matter of pushing the reset knob. I like easy solutions.

Jim, I have it (the ammeter) wired just like your instructions. Did the soldering and all. I should have the dash back in tomorrow. I'll report back!

Thanks, guys.
 
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