charging system&voltmeter gauge...

Jeremy128

Jeremy128

True Classic
I've been having charging issues. So I had my alt tested, and its not putting
out enough. Instead of buying anew one, the original one is being rebuilt as
I type, and should be finished this afternoon.
I bought a voltmeter gauge to install. I am planning on tapping into the
brown/white wire from the alt to the ignition switch. I was going to splice into this wire inside the steering column cover, and ground under the dash
also. Is this a good plan for wiring the gauge? I have read alot that says you dont want to splice into a wire that is on a fuse. So, would this work?
Also, while I am at it, I have been reading about the brown wire mod. Should I do this on a 128? If so, it sounds like the easiest way is to just run a second wire of similar gauge from the bat (parrallel with the brown), to the ignition switch. Correct?
Looking at the column with the cover removed, I see the brown wire goes into a
cast metal peice that is bolted around the steering column. I assume I need to go inside this to attach the wire. Once in there, is it a simple spade connection? Or what should I expect inside the cast peice?
As usual thanks in advance for any help you may offer.
 
Boy Jeremy... yur just all over the place...

I personally can't deal with (vague) assumptions and this post is full of them. Assumptions can mean a lot of trouble for ya!

1. For instance... your alternator... not "putting out" enough... voltage I would assume. So just what voltage was it putting out? When you get it back... what voltage would it now be putting out. You might ask the rebuilder that question. Most problems with either the Marelli or Bosch alternators have to do with their regulators and rectifiers, and it being almost impossible to vary the windings, the mods would need to be done there.

2. Most alternators are rated by output amperage... 55 - 65 amp ratings for the typical Marelli's and Bosch's that I've come across... and all I've seem have never put out more than 13.8 vdc.

3. I believe I said this before... I strongly recommend going to a GM alt at about 63 amps and 14.3vdc... all for about 60 bucks with a core. More details if ya want them...

4. As for the Brown Wire Mod... the purpose of this mod was to give the starting circuit more current handling capability and was done simply by running another wire from the battery to a CONVENIENT point near the ignition switch. Since it usually needed to be run through a firewall and the like... it is indeed best to FUSE it in case of short or accidental cut. (A good thing to do prior to this mod is to note the voltage on the Brown wire [stab through insulation] and then test again afterwards. Another way is to turn on the headlights and dash lights and install and remove the FUSE you used with the new wiring and note the differences in brightness.)

Tying the new wire to any point along the large Brown wire leading to the ignition switch, on either side of the ignition switch connector, will be fine. A typical T splice, soldered and taped is fine.

Also... note the condition of the ignition switch connector... as these have been known to burn and fail.

5. Lastly... the voltmeter guage... Well, the BEST place is to find a spot to SENSE the voltage nearest to the battery. The wire you just ran for the Brown Wire Mod would be a good choice, and the Brown/White one you mention would be another. Grounding the meter should be the same any place you can find a good chassis point or an existing "blossum".

Of note... the biggest problem with these cars is corrosion of the connectors and the poor electrical design overall, causing major voltage drops anywhere and everywhere you look. I've noted a full 1 vdc votage drop between my alternator and the battery (originally 13.8 down to 12.8) and rectified some of it by SOLDERING all the stock terminals where they were factory crimped! Simple task, and when done, I picked up about .5vdc!

Lastly, again, (and I didn't do this originally, but piece-parted it over the years...) I would TODAY install a 4 or 6 terminal auxilliary fuse box and use it for a fresh source of power for the BWM, the HRM, the horns, and a CD player or amp system. Do it all at once... at least the fuse box... so that when you have the notion to install a CD player or what not, you will have a full 12 volts at your disposal so that they will WORK!

Hopefully I have MOTIVATED you... as I believe you are in for a lot of trouble if you don't look at things from a more "specific" point of view. I hate to see folks (like I've done several times...) chasing their own tails!

We're here... good luck!
 
Thanks Tony. YOu are correct. I was all over the place when I posted that. I had about 15 things running through my head, and just started typing.
When testing the battery, at idle, it was showing a little over 12 volts. When increasing idle to over 3k RPM, it only went up to 12.6 volts.
I have been chasing my tail for a while now trying to find the source a nunfunctioning charging system (this was the motivation for the voltmeter gauge). About every week and a half, the car wouldn't start. Monday morning, after getting off work, I had to pop start it. After awrming it up enough to drive, I turned on the stereo. I was listing to a CD and noticed when the RPM dropped to idle speed, the stereo was gettign so little power, that it was turning off and on. When the RPM went up, it was fine. I also noticed, at idle, the blinkers were flashing slow. When the RPM went up, they flashed faster.
Today, my dad got a call from the company rebuilding the alternator. They were very apologetic. Since my dads shop is one of thier biggest customers, they try to get orders in and out in a couple hours, or at least the same day. Anyway, he called my dad to tell him my alternator is gonna take a day or two. I dont know why, but it doesnt suprise me. WHen I pulled the alternator off, I discovered that it was the original alternator! I would imagine that after 30 years, its pretty rough, and could use a good cleaning and replacment of brushes and such.
I do not know if this is normal with the 128, or any Fiat with the 1300, but I had a hell of a time gettign the hinge bolt out. When I finally got it out, I noticed it had some surface rust on it. This gave me a mental picture of the inside of the alt being all rusty and nasty.
THe voltage regulator was recently swapped out for a good used one. Well, it tested good a few weeks ago.
On to the voltmeter gauge....
I spent several hour tonight making a cool plate to mount the gauge on. I removed the plastic plate that held the "BRAKE" "SEATBELT" and "HAZARD" lights, along with the rheostat controller for the dash light dimmer.
I made a plate from aluminum that holds the 2" diameter voltmeter gauge, the brake, and hazard lights. I have read of several people removing the dimmer switch, and I was planning on doing the same. I am also removing the seatbelt light. I was planning on just disconnecting the 2 plugs for the seatbelt light, and keep the wires tucked away behind the plate. I do not know quite what to do with the wiring for the dimmer. Should I plug it in, turn the dash lights all the way up, then disconnect it? If I disconnect it, will the dash lights stop working? Am I corect in the assumption that the rheostat being removed will prevent the circuit from being completed? If so, would it be OK to close the circuit by making a small peice of wire with connectors on each end, and plug it to each wire for the rheostat?
Now on to the brown wire...
You said to note the condition of the ignition switch connector. I guess I need to remove the metal housing around the switch? I took the plastic steerign column cover off, and still cannot see the switch. It appears to be completely surrounded by a 2 piece cast aluminum set up, that goes completely around the column, and bolts together. I need to take this off right?
I have always read about ignition switches om the spider having multiple spade connectors. Any of the connectors, can be used to attach the wire for the brown wire mod. Do you know if this is the same on all Fiats? Can I take off the metal pieces surrounding the ign switch, and just use a spade connector in to it? Or is there more to it?

So, in th emen time, I have my dash partialyl torn apart, the column covers laying on the floor, the plate I made was just painted and is drying, and I successfully snaked the positive wire for the gauge through the dash over to the column. SO I can go ahead and splice this wire to the brown and white wire then?
Sorry I rambling..... Gettign sleepy.
 
My 2¢

The ignition switch "connector" is about 8" away from the switch in the wiring. No need to remove the switch. Just unplugging it and re-plugging it cleans the connections, do this several times. If you see discoloration in the plastic of the connector blocks, then you have a loose wire terminal in the connector or a high amperage load (from resistance or other trouble).

The "brown wire mod" provides more power to the ignition switch, so that switches accessories like headlights, heater fan, etc. have more power available. The ignition switch can still be a weak link.

Ultimately your charging system problem might simply be a series of loose, dirty or corroded connections. Even battery terminals can corrode in a hidden manner and cause a low charge. When faced with these issues, I like to "loop the loop" and start at one battery terminal and following the wire(s), clean and tighten (sometimes soldering) the connections along the way to the alternator, then back through the ground path to the battery. The ground path is often overlooked.

Hope this helps! :hypno:
 
I do not know quite what to do with the wiring for the dimmer. Should I plug it in, turn the dash lights all the way up, then disconnect it? If I disconnect it, will the dash lights stop working? Am I corect in the assumption that the rheostat being removed will prevent the circuit from being completed?
Click to expand...
Yes, removing the rheostat will leave your dash lights not working.
If so, would it be OK to close the circuit by making a small peice of wire with connectors on each end, and plug it to each wire for the rheostat?
Click to expand...
You can do that, and it will leave the dash lights at max brightness. Just be sure you know which wire is which. I have not seen the wiring diagram for the 128 since my dad sold the '78 in '82, but on the X the rheostat has three connections: ground, power (from the ignition switch) and output to the dash lights. Connecting ignition power to ground with a jumper wire would not be such a great idea...

Could you leave the rheostat connected, but tuck it behind the dash?
 
Greg,
I just looked at the connector on the column again, and verified that there is no discoloration, and everythign appears clean. So I can just tie into the brown wire before the connector plug, and that would be OK?

As you and others have said, it would be a good idea to check and clean all connectors, folowed by solidering. Always a good idea. I will get to that in time.
 
Pluggig it in, and leaving it inside the dash as another option. In fact, it sounds like the best option. The plate I made can be easily moved/removed. So if there are any problems, I just take it off, fix the prob, and put it bcak on.

Here is the before

128pics038.jpg

By jeremy128, shot with COOLPIX L14 at 2009-07-03

Here is the after

dash2.jpg

By jeremy128, shot with SPH-M540 at 2009-07-03

dash4.jpg

By jeremy128, shot with SPH-M540 at 2009-07-03

dash1.jpg

By jeremy128, shot with SPH-M540 at 2009-07-03

I intially wanted to make the aluminum plate longer for future installation of oil pressure gauge, and maybe other stuff, but decided not to. It looked weird with a big blank piece of metal just sitting there. THis is my first attempt, so I'll tweak it more as it goes.
 
As Gregory said...

Yes... You can splice into the Brown wire at any convenient point before or after the connector. PLEASE use a fused wire from the battery... and with all the stereo issues... I suggest you run another fresh new fused wire for the (usually Pink) lead to your radio or CD player.

Lastly... when you get the fresh alternator installed... Use yur VOM to test the output voltage at:

1. The output STUD on the alternator.
2. The TERMINAL END of the wire leading from this stud.
3. The WIRE itself (stab through the insulation)
4. At EVERY SINGLE CONNECTOR... as it leads to the battery up front. (Oh, I forgot this is a 128... but the philosphy still applies.)

I think you will find that there is a voltage DROP of a 1/10 or so at every junction. Melting solder into the terminal ends where they are crimped can help remove this issue.

The voltmeter looks good... BTW... and should be attached to the battery itself, or close to it.

BTW, a 12.6v output from the alternator is NOT much of an output... IN fact, its what a normal battery should look like. Which means the alt was not really functioning much at all, maybe .4 volts. It should but out at least 13.8 tp 14.3 volts. Also... the stock VRs and Rectifiers are also very fragile. Jump starting another car will usually kill them... guess how I know...

SO... for the LAST TIME... if those folks haven't got this alternator together by Monday... ditch it, and go with a GM. Jiminy will give you details. You'll be GLAD you did!

Send the monetary savings to me...
 
Thanks Tony. All good advice. The one place I take exception too is the jump starting. While it can kill a VR, I have never jumpe the car. I always pop start it. I wise Fiat Mater once told me "Always park your Fiat on a hill, facing downhill, and never try to pop start it while rolling backwards". I religously back my Fiat up my driveway, and into the garage.
Are you trying to get me in trouble with JimD? Sheesh, I borrow the VR from his extra X, and you accuse me of breaking it!!!! :fart:
 
OK, update time. I got the lat back the other day. I didn't have time until today to get it bak in the car.BTW, that was the BIGGEST P.I.T.A. alternator I have ever remove and reinstalled! It took about 2 hours to get it out, and another 2 to get it back in the car! WHen I remove it, I had to cut the old belt. THis was a clue that the install was gonna be a bitch. I thought someone at some point put the worng belt on it. So I cross referenced the part # on th ebelt. I then looked it up in the computer at my dads store. THey were the same part #.
I could not get the belt over the alt pulley after it was placed over the w/p, and crank [ulley. I was forced to remove the tenision bracket to get enough slack to get the belt over the puilley.
I wired the voltmeter to the brown/white wire that runs from the alt, to the ing switch. After hooking everything up, I was quite impressed withmyslef that I did this without screwing it up! Everything worked! The wire fron alt to ign switch is apparently always hot. WHn the var is parked withkeys out, it still shows voltage. I guess this could be an issue it I let the car sit for a long time..... HUH?
At idle, the voltmeter is showing just under 13v. When I rev the motor, it goes up to just over 13v. I did noticed, when I turn on my parking lights, it drops to around 12.5, when the headlights are on, it drop to just above 12 v. Ideas? I have afeeling that this is not supposed to happen. Brown wire? SHort? What?

Forgot to mention, while lookng over the charging system, I noticed something I overlooked before. My battery is not sealed. I checked and the water/acid level was low. So I topped it off with distilled water. I guess this is a contributing facot. It was pretty low. So, after taking it for a run a couple hours ago, I hooked it up to the trickle charger.
 
I ordered a new VR... just in case.

Poor little VR... It never had a chance. sniff. ;)
 
Sounds like you need to

move that VM wire to the other side of the ignition switch so that it gets "switched" with every thing else.
 
GM alternator specifics

So, what are specifics? Part number or body model source? Bracket info, etc.
 
Check the "Best of" section at Xweb 1.0

The info can be found there.
 
12.5 is low

Try measuring the voltage at the alternator, engine running and headlights on. Test at idle and then increase the engine RPM. The spec for the X1/9 is 14.0 V +/- 0.2, I would be surprised if the 128 is different. It is not unusual for the voltage to drop a bit at idle, but as you increase the RPM the voltage should come up to 14 +/- 0.2 and then stay stable as you keep increasing the RPM.

How old is your battery?
 
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