Alternator Help Please.

[fjatheart]

I adjusted the points on the VR and did not show any change in the Voltage. Does this sound strange?

I went to Advance and had them check the Alt. The results is charge battery and test again, but here are the readings.

Voltage with no load 12.19v
Measured 436 Cold Cranking Amps (rated at 750)
Battery with Lights and heat on 11.89v

Things to check:
-charge system problem
-check belts-duh!
-cables and connections-duh!

Start Test:
-low cranking amps
-volts at 11.62
-amps at 0.3 (Tested 3.28 mins)


Guy at Advance thinks I have too much stuff hooked up to the battery and not a big enough Alt. to keep it charged.

This is what I have hooked up to it:
-arb compressor
-aux fuse panel with trouble light from an old Ford
-radio-hooked to aux fuse panel
-MSD multi spark directly to battery
-CB radio-hooked to aux fuse panel
-Atlas winch hooked directly to top post


Does this change you guys thought's on my problems?

Thanks...again..

 

[bsmith123]

vr wiring

check the wiring between the VR and the alternator. it is odd the adjustment made no diff. I would disonnect both ends and use a load lamp on it---you can use one of your marker lights---just wire it up to run a circuit through the light and turn the light on. This will give you a better idea if the wire is good than just a continuity check.

You are right the alt should put out 14 volts

as far as too much stuff ---you said the ammeter is staying straight up in the middle ---0 right? That should mean the charging and discharging rate are at a balance---but that should be at 14 volts or so not at 12 ---sounds like you are undercharging not overworking---but the question is still is it the alternator of the VR---?

when it goes to the left of zero that means you are draining the battery and when it goes to the right you are charging.

Not all the stuff you have puts a drain on the battery unless you are actually using it all at once

If you turn on all your lights and accessories does the meter move to the right or left?

 

[fjatheart]

Will do.

Also, I just realized my Ammeter is NOT working. The needle is stuck straight up!

I'll try to figure that out first and then tackle tracing the wire between the VR and Alt.

Thanks again Bsmith123

 

[bsmith123]

ammeter

Hmmm I need to check the schematic now and see what that could cause

 

[bsmith123]

ammeter

Okay I went to the 71 schematic cause I use it all the time


If your circuit is the same you should have 2 wires on the ammeter to + and _

the white one to the battery and the white/blue one to the alternator

check for voltage in on the white/blue one --that should be the 14 volts from your alt

check the white wire and see if it is reading 12volts or the same as the battery

I am thinking if you are running your winch off the main battery then you are overloading the ammeter and maybe have burnt it out

Sounds like the alternator voltage is stopped at the ammeter and not getting into the battery circuit to charge it

 

[bsmith123]

ammeter

this may help put it in perspective

 

[fjatheart]

Hmmm...
I never thought of that causing a problem...going to check it out and let you know.

Thanks so much!

 

[Greenweenie40]

Sorry for the hijack but are all 2f alternators internally regulated? I have one that does not have the box mounted to the outside of the alt like the one pictured above but it is from a 2f and my cruiser is 1970 and 1f? can I use the 2f with a regulated system?
Thanks.

 

[Coolerman]

Sorry for the hijack but are all 2f alternators internally regulated? I have one that does not have the box mounted to the outside of the alt like the one pictured above but it is from a 2f and my cruiser is 1970 and 1f? can I use the 2f with a regulated system?
Thanks.

No, the earlier 2F alternators were externally regulated just like the F alternator. 2 versions were available 40 amp and 50 amp.
I'm not sure when the externally regulated alternator became available.
The regulators will be the same except maybe for the plug on the end. The regulator only has to deal with rotor current not output current.

So yes the 2F alternator will work.

 

[Coolerman]

Will do.

Also, I just realized my Ammeter is NOT working.

No Amp meter, no charge.

You will need to recheck your regulator settings after you repair the amp meter.

A quick way to 'fix' this: DISCONNECT THE BATTERY!!! Do NOT ignore this advice! Remove the gauge cluster. (If you ignored the above you will now know why I suggested this.)

Remove the white and white/blue wires from the amp meter gauge. Use a small bolt to tie the two wires together. Wrap with lots of tape. Set the gauge cluster back in place. Re-test the system as explained above, it should now charge.

Check the regulator again!

 

[bsmith123]

VR

x 2 it's important to check the voltage again since you messed with the contacts on your vr it may have changed now

I am thinking the winch was the culprit ---do you know how many amps the winch pulls---is there a HP or WATT rating on it anywhere?

 

[fjatheart]

So, after the wires from the back of the amp meter are connected(taped together) and the guage cluster is back in place, THEN CONNECT THE BATTERY TO TEST? Also, my gauges have two harnesses plugged in the back. Behind the amp meter is a small harness with a black wire, white/black and the white/blue. Should I connect the jumper wire from the white/black to the white/blue?

Thanks

No Amp meter, no charge.

You will need to recheck your regulator settings after you repair the amp meter.

A quick way to 'fix' this: DISCONNECT THE BATTERY!!! Do NOT ignore this advice! Remove the gauge cluster. (If you ignored the above you will now know why I suggested this.)

Remove the white and white/blue wires from the amp meter gauge. Use a small bolt to tie the two wires together. Wrap with lots of tape. Set the gauge cluster back in place. Re-test the system as explained above, it should now charge.

Check the regulator again!

 

[Coolerman]

Yes on reconnect the battery after the gauge is in place.

Well duh...I just looked at a 1978, 81 and 83 schematic. They are all different from an early FJ40. I would have to guess you do not have an amp meter like the older FJ's.

On a 1978 there is a fusible link in the White line near the battery. If that's what you have, check that to see if it's melted. If it is then you will not charge. I bet your 80 is like this setup.

The later 81 and up FJ's seem have a remote shunt (it's actually a fusible link) that the amp meter is in parallel with instead of an internal shunt. This keeps the high currents out of the cab. If you have this setup, follow the lines from the amp meter to two in line, 5 amp fuses that are taped up in the harness under the hood. The fuses are to protect the meter only. Follow the wires from the fuses till you come to a fusible link. These wires from the fuses will attach to each end of the link. If the link is melted then you will not be charging. This setup has a White/Blue and a Black wire connected to the meter.

We need Pin_Head to help answer this one...

 

[fjatheart]

I checked my wire diagram and the black wire and the white/blue wire go directly to the amp meter. I connected the wires with a jumper wire, taped and then hooked-up the battery. I cranked the Cruiser and got a reading of 12.3 at the Alt.

I then rechecked the VR. I only get 12.3 volts on the right/driver side of the VR points and nothing on the left/passenger side points. Could part of the VR be faulty?

 

[fjatheart]

Yes, the white/blue and black wires are part of the fusible link that also have glass fuses in line.

The fuses and the connections on either end are good as well.

I had the fusible link pop/burn thru back in Oct. and replaced it. Do you think the damage to the VR or Amp meter could have been caused then? Could both be burned as a result?

 

[Coolerman]

OK lets back up a sec here. Undo what you just did. Now that we know you have the more modern amp meter it's a different ball game.

You replaced the fusible link that the amp meter wires go across right? What did you replace it with? Hmmm.. doesn't really matter since it must be good. You can start the truck and have power everywhere.

The alternator tested good as did the battery.

OK, remove the cover off the regulator, and start the truck. Turn on every electrical accessory except the winch. Rev the engine to about 2000 rpm. If the regulator is working you should see the arm BETWEEN the points sort of vibrating back and forth between the two points.

If you don't see this then verify that the regulator CASE is grounded. The ground is a white/black wire that goes between the alternator and the regulator AND goes to the chassis. Then check the the alternator itself is grounded to it's bracket. File off any paint where the alternator ears touch the bracket. You might even want to connect a separate wire to the case just to make sure.

If after that it still doesn't charge, replace the regulator...

Ain't electrical problems fun?

 

[bsmith123]

charging

Shoulda checked the newer schematic--I like the 71 cleaned too much!

here is the schematic from the 81 cut an pasted around a little to make it small---with an internal shunt you should be okay without the ammeter as Cooler said. It appears the fuses just protect the wiring to the meter if it shorts out or maybe to keep it from drawing down the rest of the system.

In any case it looks like a straight shot through the fusible to the alt

Since everything is working and you are getting some voltage from the alternator and the VR controls the voltage it is sure sounding like that

Here's a couple of things to add if you are still stuck

I read a couple sources saying that the field post on the alternator should read 3-6 ohms,

Also, check the wiring resistance from the F on the alternator and the one from the B

B is the control voltage source and senses battery voltage
F controls the amount of current that is output to the alternator which in turn controls how much the alternator puts out
when B drops low, F current is increased

I cant see B doing it but i threw that in---high resistance on f would reduce current to the field and the resulting magnetic field from it and ultimately alternator output--make sure the connections are clean and the wire resistance is low

 

[fjatheart]

Okay, I checked the grounds, fusible link, and amp meter fuses and all checks out.

I started the Cruiser and brought it up to 2000rpm and checked the VR once more. Nothing changed on the VR and the points did not vibrate back and forth.

Still think it is the Alt??

 

[Coolerman]

The alternator tested good at AutoCrap right?

Besides wiring it can only be the regulator at this point....

 

[bsmith123]

Full field testing

The alternator tested good at Auto**** right?

Besides wiring it can only be the regulator at this point....

x2

if it were battery sensing It wont sense extra voltage right? So a bad wire there would probably cause overcharging

The field wire on the other hand could reduce current to the alternator with high resistance

I think that is a long shot but did you ohm into the alt field from the VR on the wire? If so what was it reading?


I've never asked how they set it up but when they test the alternator they probably do a full field test--- You disconnect the VR and jumper B to field and the alt puts out full current/full voltage- You can read this on a meter

This can be done in a car to shoot down between the alt and the regulator but the battery is soaking up the spike and you have to be careful with the wiring not to touch anything with the full current flowing so prob safer to just pull it and have it tested. If they said the alt is OK and the field wiring checks good then yes the VR must be bad.

I am not saying to do it just explaining---with a full field test the ALT is putting out max current and thats quite a bit, but it does show if it is capable of putting out greater than the 14+ volts required for charging that is how it proves the regulator bad rather than the alternator---This is where it is good to ask the guy at the parts place how much voltage and amperage it put out.

if that check was good it has to be the VR or the field wiring I would say

You definitely get Cruiser Karma points for sticking with the troubleshooting--most would have defaulted to cash and hope by now and swapped 2 or 3 parts