As JF said, the simplest way to cure this- if it bothers you- is to tighten ALL the connections, especially the multiple grounds and add a shunt across the amp gauge terminals. This is a fix that came out when the Pantera was still being sold by Ford, so needle-waving is not new and probably is not harmful.
The second fix many use is to use an internally regulated modern alternator and discard the separate regulator. That way there is zero question as to whether the regulator is solid- state or uses contact points, and it has the advantage of allowing a bigger alt. If you do this and go to a simple-to-install single wire alt, some need the idle rpms set up higher to begin charging at low rpms. Other single-wires do not; ask before paying.
The stock Motorcraft alt was 47 amp (some identical appearing were 61 amp,) and both are simply too low in output to supply AC, headlights/tailights/stop lights, a stereo & CB and other accessories, at low rpms in heavy evening traffic. Owners have had the engine die in traffic jams and then find they'd been running on the battery for some time & do not have the juice to restart. Tow trucks love evening rush hours....
Bosswrench,
thks a lot! I have already installed a shunt according to your spec. Unfortunately no success. I also have put an additional ground wire to the regulator. I will check the further connections, too. Keep my fingers crossed...
thks a lot! I have already installed a shunt according to your spec. Unfortunately no success. I also have put an additional ground wire to the regulator. I will check the further connections, too. Keep my fingers crossed...
wolfgang, do you have access to a voltmeter?
from your utube, I think you might have a bigger problem than the normal amp meter waving.
from what I have read recently, IF it were me, given I sort of know how alternators/regulators work, I would put a swtich and one of those small audio "stiffing" capacitor on the altenator field terminal. those caps are about $10 at an electrical parts store. But with out watching voltage you could over charge the battery.
from your utube, I think you might have a bigger problem than the normal amp meter waving.
from what I have read recently, IF it were me, given I sort of know how alternators/regulators work, I would put a swtich and one of those small audio "stiffing" capacitor on the altenator field terminal. those caps are about $10 at an electrical parts store. But with out watching voltage you could over charge the battery.
JFB,
I have a voltmeter and check out the points you have mentioned as soon as I find the time. Great, thank you!!
I have a voltmeter and check out the points you have mentioned as soon as I find the time. Great, thank you!!
proceed at YOUR OWN risk!
I would first try a 0.1 F (1000uF), it needs to be rated above 20VDC. using a switch so I can put it in service and back out quickly if needed. it woulg go on either end of the wire going to the altenator field and the other end to ground.
the cap would act like a fast charge/discharge battery. so when the regulator steps the field current to max, the cap charge will cause it to ramp. when the regulatos steps to zero, the cap will cause the current to ramp down.
the time of the ramp depends on the cap size and the resistance of the circuit. from some online info, I think there is a 50 ohm resistor on the field wire to ground. thus with a 0.1F, the ramp from 0 to 80% will be 0.05 secs. this would reduce a charging cycle frequency of 3 htz and greater.
PS...
I found a good writeup on how to test the regulator.
http://www.fordification.com/tech/charging.htm
towards the bottom of the page there is instructions on disconnecting the regulator and using a jumper to apply full field. IF the amp meter is waving with the jumper (and the belt is not slipping) I would think the problem is bad connections in the wiring
I would first try a 0.1 F (1000uF), it needs to be rated above 20VDC. using a switch so I can put it in service and back out quickly if needed. it woulg go on either end of the wire going to the altenator field and the other end to ground.
the cap would act like a fast charge/discharge battery. so when the regulator steps the field current to max, the cap charge will cause it to ramp. when the regulatos steps to zero, the cap will cause the current to ramp down.
the time of the ramp depends on the cap size and the resistance of the circuit. from some online info, I think there is a 50 ohm resistor on the field wire to ground. thus with a 0.1F, the ramp from 0 to 80% will be 0.05 secs. this would reduce a charging cycle frequency of 3 htz and greater.
PS...
I found a good writeup on how to test the regulator.
http://www.fordification.com/tech/charging.htm
towards the bottom of the page there is instructions on disconnecting the regulator and using a jumper to apply full field. IF the amp meter is waving with the jumper (and the belt is not slipping) I would think the problem is bad connections in the wiring
In the meantime I have put a separate ground from the regulator to the chassis. The result is very positive; the bouncing needle has calmed down considerably. I still have some bouncing at low revs and the next step will be to buy a new connector plug (correct wording????) for the regulator in order to have good connections here, too.
If I have no success with that I will try out the "JFB-checking procedure"!
I`ll report!
If I have no success with that I will try out the "JFB-checking procedure"!
I`ll report!
Good to hear you got the center to full scale waving reduced. from what I surmized, the minor bounce sounds like it would the regulator switching from full field to half field now. Charging voltage should be right at normal.
the check out procedure while at idle (where you now see the bounce) of forcing full field current should stop the bounce, But if idle is where the regulator is trying to reduce voltage, going with the full field jumper will raise the voltage and begin to over charge the battery, so monitor and keep the duration to a minimum (30 minutes if voltage is say less than 14 VDC, less if greater)
the minor bounce at regulator switching is a good canidate for a smoothing capacitor
the check out procedure while at idle (where you now see the bounce) of forcing full field current should stop the bounce, But if idle is where the regulator is trying to reduce voltage, going with the full field jumper will raise the voltage and begin to over charge the battery, so monitor and keep the duration to a minimum (30 minutes if voltage is say less than 14 VDC, less if greater)
the minor bounce at regulator switching is a good canidate for a smoothing capacitor
I have to analyze better, at what revs the needle still bounces. At idle there is no bounce. I will check that out!
I can imagine the operation of the altenator and regulator be sort like
from idle up to X rpms, the regulator will be the full field setting given the output of the altenator is very speed dependant. at idle, the charging voltage will be low and as rpms increase so will the charging voltage up to the desired value.
when greater than X rpms, the regulator has to start switching between full and half field to keep the desired charging voltage. as speed increases the switching will stay longer at the half field state up to the speed Y in which half field alone is sufficent.
I don't think there will be much of a speed range above Y where the regulator stays purely at half field, but will start switching from half to no field. My anysis of the circuit does cause me to have questions when this occurs as it appears the relay to switch from self feed back to battery feed may occur when zero field switching. so maybe there is some built in dead band to have a high rpm zone with just half field and zero field only needed at extreme high RPM
IF you care to take some data
----RPM------|--VDC--|--VAC--|--Freq--|--ampmeter wave--|
(every 200)..............................................yes/no
Thats just my two cents
these types of questions makes me wish I had started the rebuild on mine when I had access to vast diagnostic instrumentaion
from idle up to X rpms, the regulator will be the full field setting given the output of the altenator is very speed dependant. at idle, the charging voltage will be low and as rpms increase so will the charging voltage up to the desired value.
when greater than X rpms, the regulator has to start switching between full and half field to keep the desired charging voltage. as speed increases the switching will stay longer at the half field state up to the speed Y in which half field alone is sufficent.
I don't think there will be much of a speed range above Y where the regulator stays purely at half field, but will start switching from half to no field. My anysis of the circuit does cause me to have questions when this occurs as it appears the relay to switch from self feed back to battery feed may occur when zero field switching. so maybe there is some built in dead band to have a high rpm zone with just half field and zero field only needed at extreme high RPM
IF you care to take some data
----RPM------|--VDC--|--VAC--|--Freq--|--ampmeter wave--|
(every 200)..............................................yes/no
Thats just my two cents
these types of questions makes me wish I had started the rebuild on mine when I had access to vast diagnostic instrumentaion
JFB,
I still have to do the checking process you have suggested. Will do that asap.
I have built in a new 4pin system connector leading to the regulator as my old connector really looked pretty worn. Unfortunately no success.
While doing that I have noticed that a suppression capacitor is connected to the regulator. Any idea whether a bad capacitor could have to do something with my bouncing ammeter needle? I could not find out the exact type of the capacitor....
Wolfgang
I still have to do the checking process you have suggested. Will do that asap.
I have built in a new 4pin system connector leading to the regulator as my old connector really looked pretty worn. Unfortunately no success.
While doing that I have noticed that a suppression capacitor is connected to the regulator. Any idea whether a bad capacitor could have to do something with my bouncing ammeter needle? I could not find out the exact type of the capacitor....
Wolfgang
I don't know for sure. the normal "radio suppression" cap is on the Yellow supply wire from the battery to the field. I think its purpose would be to filter out the radio wave noise caused by the regulator switching field current on and off at 100 hz. I don't see how it could effect the altenator output current.
Is your cap on the yellow?
Is your cap on the yellow?
Oh yes, it is on the yellow. Was just and idea..... Ok, the search goes on.
Wolfgang
Wolfgang