87 Ranger V8 swap gauge questions

[Bird76Mojo]

I don't think it's working correctly. It has never gone above the center position. Plus I know that I don't have all of the factory wires hooked up correctly.

It's charging well over 14 volts all the time. That's what I don't like about the Ron Francis alternator harness. It forces the alternator to charge all the time.

I wish I could find a voltmeter that fit the factory ammeter location and looked oem. I may just have to find a digital voltmeter and retrofit it in to that space.

 

[bobbywalter]

The red/orange wire and yellow/light green wire are in the cab but would HAVE TO have been out in the engine bay for the amp meter to work.

No, on "changing" the Ranger Amp meter to a Volt meter, way way easier to just hook amp meter up, or just buy a digital volt meter and plug it into the Cigar lighter, seen here WITH USB hook ups, lol: https://images-na.ssl-images-amazon.com/images/I/51rM0Hd8LLL._AC_SL1100_.jpg
Or hook one up under the dash

Or just put the volt meter cluster in.


I reread my previous post....it's definitely missing order of operations context.

I am saying....first.....from the gauge....run one wire right to the alternater post....and the other right to the battery post on the starter relay....equal length if possible.


Tune from there.

 

[RonD]

Alternator wiring has no connection to ANYTHING in the engine wiring, its self contained, only thing it needs is a 12v Key ON connection as the ON/OFF switch, the "I" wire

2G and up have 2 wires to battery positive and 1 wire to Key ON 12volt, that's it, that's all there is to it
Everything 2G and up is the same, 3 wires

You battery WILL not last as long running at over 14v charging, the "A" connection on alternator is for the "pushback" that reduces charging under 14volts after battery has been recharged
When engine is running battery is ALWAYS being charged, but best is 1 volt over "at rest" voltage
At rest is the voltage of battery after it as sat overnight and before starting engine
12.3v to 12.8v is expected
So if battery is 12.5v then alternator should put out 13.5v AFTER battery has been fast charged for 5 to 10 minutes after start up


Trace the black/orange and yellow wires, see where they go, should come across one of your Amp meter wires

 

[Bird76Mojo]

Or just put the volt meter cluster in.


I reread my previous post....it's definitely missing order of operations context.

I am saying....first.....from the gauge....run one wire right to the alternater post....and the other right to the battery post on the starter relay....equal length if possible.


Tune from there.

I thought about swapping the left side cluster for the tach model, but then I'd lose my oil pressure gauge, and that is not acceptable to me.

I have a spare ammeter from a broken cluster that I salvaged from the junkyard. I'll test your theory and wire it alt-----ammeter-----battery
but I'm sure it will smoke it without the factory shunt in place, which I'm 99% sure was in the oem alternator harness.

 

[bobbywalter]

Alternator wiring has no connection to ANYTHING in the engine wiring, its self contained, only thing it needs is a 12v Key ON connection as the ON/OFF switch, the "I" wire

2G and up have 2 wires to battery positive and 1 wire to Key ON 12volt, that's it, that's all there is to it
Everything 2G and up is the same, 3 wires

You battery WILL not last as long running at over 14v charging, the "A" connection on alternator is for the "pushback" that reduces charging under 14volts after battery has been recharged
When engine is running battery is ALWAYS being charged, but best is 1 volt over "at rest" voltage
At rest is the voltage of battery after it as sat overnight and before starting engine
12.3v to 12.8v is expected
So if battery is 12.5v then alternator should put out 13.5v AFTER battery has been fast charged for 5 to 10 minutes after start up


Trace the black/orange and yellow wires, see where they go, should come across one of your Amp meter wires

Since the truck is molested and old and the charge harness is as well..I would just start fresh. Though....I agree...at the apron they are probably fine and I would jumper and prove from there if this critter was near me.

But since it's been apart several times...and no telling if anything was burned in the attempts....those old plugs hide corrosion...

 

[bobbywalter]

I thought about swapping the left side cluster for the tach model, but then I'd lose my oil pressure gauge, and that is not acceptable to me.

I have a spare ammeter from a broken cluster that I salvaged from the junkyard. I'll test your theory and wire it alt-----ammeter-----battery
but I'm sure it will smoke it without the factory shunt in place, which I'm 99% sure was in the oem alternator harness.

Why would it smoke it....? You keep it on the same line. No grounding...

The distance between the two posts will offer enough resistance. You can close or open the gap to suit. If you have to open it....make a backwrap shunt....

 

[Bird76Mojo]

The alternator is wired the way the Ron Francis harness is built. Charges all the time from what I gather.. https://s3.amazonaws.com/cdn.ronfrancis.com/downloads/INSTRUCTIONS/AH23-INST.pdf

So far the battery is several years old and has been flawless. So we'll test out that theory about it decreasing the battery life..

I've tried to jumper test the ammeter but nothing I do will make it show a charge condition while running. With the original 4cyl it would show charging very well on the gauge. Removing that factory alternator harness (shunt) is what screwed me. My theory is that without the factory shunt in place, I'm not forcing any power through the ammeter, no matter how I have it jumpered.

 

[bobbywalter]

Aye.


Maybe I am understanding it wrong..but
A shunt is micro resistance in this case....as it shows it in the diagram you posted.


And it is exactly that.

Just do it.

 

[Bird76Mojo]

I just emailed Rocketman to see if he'll convert the factory gauge to a voltmeter. He does do custom work.

Rocketman's Classic Cougar Innovations

www.rccinnovations.com

....aaaaaand he's traveling from June 1 - June 14 soo..... crap

 

[Bird76Mojo]

He responded today and told me he could do it, and he just finished one for someone else last week. I think this is the route for me to take. It'll tell me all I need to know about my charging system.

 

[bobbywalter]

I was gonna say pussy...

But yeah....I would do that.

 

[bobbywalter]

 

[85_Ranger4x4]

I thought about swapping the left side cluster for the tach model, but then I'd lose my oil pressure gauge, and that is not acceptable to me.

You do gain the pretty red light of doom though!



I don't know how super awesome the factory oil pressure gauge was. It always said the same thing at idle or going down the highway. My autometer varies a lot more depending on if the engine is at idle or wound up at flank speed. And I have a idiot light to get my attention now if I have next to no oil pressure.

I do need to figure out how to get the charging idiot light to work sometime though. But I have a volt meter living beside the oil pressure gauge on the bottom of the dash in the mean time.

 

[Bird76Mojo]

Depending on the sender one uses, the oil pressure gauge can actually be pretty nice. Mine shows very high oil pressure when cold, and after warming up it will drop an expected amount on the gauge. Sure, it doesn't have PSI numbers, which would be nice, but it does let me monitor my engine vitals. I've also been thinking about adding an oil cooler since it would be so easy with the filter relocation kit..

One thing I recently learned is that you can very easily raise your oil pressure by simply switching your oil filter to a different model. I used to run the Wix 51515 - I believe, and I switched to the Wix 51085 (since that's what I run on my Allis 720, and it raised my oil pressure a good bit on the gauge. It's a smaller (shorter) filter but the reduction in oil capacity is negligible and it clears my new front sway bar a bit better as well.