Adjusting the voltage regulator.

Chaz · November 03, 2008, 02:09:14 PM

My regulator seems to be putting out a little more than it needs to. (Dallas caught that)
We pulled the little screw out and stuck a small phillips head in there and turned it back about 3/4 turn. The meter on the dash on the way home showed it was just slightly in the red on the "undercharge" side now, so it seems I need to turn it back up just a little bit.
Is there a way I can put a VOM on the poles at the reg. and see what I am getting as I turn the screw?? I suppose the book "might" tell me but, I just don't want to go figuring stuff out yet again. I'm kinda burnt out, ya know?

Thanx guys,
Chaz

Dreamscape · November 03, 2008, 05:05:50 PM

Hi Chaz,

Glad to hear from you on another subject for a change!

I had to adjust mine because it was undercharging the batts. I would strongly suggest you get the book out and read it before you do anything, then read it again. It also helps to have a good digital meter to get the optimum results. The potemtiometer is touchy, and don't short any wires or it will be toast.

Not sure what kind of voltage regulator you have but it's pretty straight forward. You just want to adjust it properly so you won't have problems down the road.

And did I say, Read The Book!

HTH,

Paul

Sojourner · November 03, 2008, 06:37:32 PM

Chaz...as what Dreamscape posted and use long spare wire (any light gauge) from meter to connect directly on + post of the battery to by pass the resistant differential voltage.
Caution whenever you adjust regulator:
1)   Make sure your battery is at least 85% charged before the adjustment.
2)   Make sure regulator is at 80°F via running 15 minute full charging (all lights on & blowers} if possible.
3)   After 15 minutes warm up, keep the lights & blower on to adjust.
4)   Always...it very important to turn clockwise to the spec setting. In other words, always start at lower end of the spec setting to adjust up. Never adjust downward.
5)   The reason is that the alternator have magnetic residual field left to be lowered in order to get accurate adjusted setting.
6)   Temperature of voltage regulator is very important before adjustment can be made final. Around 80°F.
7)   Happy motoring.

FWIW

Sojourn for Christ, Gerald

Jerry Liebler · November 03, 2008, 06:43:19 PM

Chaz,
It sounds like the engine is back together, we are all glad to hear that! About the voltage regulator. Follow the book's advice if at all possible. The important voltage to measure is right at the battery terminals when the engine is running at fast idle and the battery has been fully charged. If the books don't advise otherwise I'd go for 27.2 volts on a good DVM.
Regards
Jerry 4107 1120

Sojourner · November 03, 2008, 09:10:13 PM

Thanks Jerry for reminder about the battery need to be fully charge or my experience to be at least 85% charged before the adjustment.

Sojourn for Christ, Gerald

Chaz · November 04, 2008, 06:13:44 AM

Thanx for the advice guys!!!!!
I did read the book last night and it was no where near as detailed as you have just told me. Basically it just said turn blowers on and put meter on pos. and ground and set to 27.5.
I will follow your instructions as they are MUCH more thorough.

As ususal, this board is the ultimate!! Thanks again!

Chaz

Jerry,
Yeah the engine is back to gether and ran great. I'm going to start it later today and make sure all is well.................... but I'm afraid my dream is going to have to fade away.

Chaz · November 05, 2008, 01:03:39 PM

Well...........
She was showing about 24.6 with a little fluctuation on the meter. I couldn't get straight into the screw on the pot so I opened it up to get a better shot at it................................... and Paul is right....... don't short it.

I accidentally let something on the back of the PC board touch the case and now I think I need a new one. DAMN!!!!!!!!!!!!!!
It doesn't have that fluctuation any longer so it may be toast. I will look into it further but do any of you guys know a good source for a 24v regulator?? I may be looking for one soon.

Thanx again,
Chaz

Chaz · November 05, 2008, 03:59:45 PM

Ok, scratch the last. I just took her for a ride and it still works................ I guess, kinda. At idle she is down around maybe 24v and driving she is up around 28-29v. So I guess I need to do my adjustments yet. I guess I'll just rev it up pretty good and do it then as I can not tell the rpm's exactly.
Do you know if it will take "allot" of turning of the screw??

Thanx,
Chaz

Dreamscape · November 05, 2008, 05:25:10 PM

The potentiometer is touchy, should not take too much to make a change. Get it as close as you can then run it a while and then go back and check it.

Good Luck,

Paul

Sojourner · November 05, 2008, 11:45:45 PM

Chaz...did you turn on the lights and blowers or fans to put a load so that alternator will charge heavy before adjusting regulator? If not, read my step by step post about adjusting regulator.

FWIW

Sojourn for Christ, Gerald

Chaz · November 06, 2008, 06:38:59 AM

Yeah, I had the headlights on and the defrost on. I think that is about all the heavy current draw I have. The rest is on house power. By the way, the measurements I spoke of were what was on the dash gage, so I know they are not spot on.

I "suppose" there is that much fluctuation in an alternator charging between idle and driving, but not sure. I will rev her up pretty fast the next time I get a chance to adjust it. I may not have had enough rpm's. I'm a little timid at revving a motor up too much when sitting still. I know it isn't a big deal, it's just me. And I don't have a tach.

In order to turn the pot "up" while adjusting, should I back it down first (counter clockwise) before I start the engine, and then adjust it up (clockwise) to the proper setting?? I really don't want to mess it up.

Thanx guys,
Chaz

Sojourner · November 06, 2008, 11:40:56 AM

Quote from: Chaz on November 06, 2008, 06:38:59 AM
Yeah, I had the headlights on and the defrost on. I think that is about all the heavy current draw I have. The rest is on house power. By the way, the measurements I spoke of were what was on the dash gage, so I know they are not spot on.

I "suppose" there is that much fluctuation in an alternator charging between idle and driving, but not sure. I will rev her up pretty fast the next time I get a chance to adjust it. I may not have had enough rpm's. I'm a little timid at revving a motor up too much when sitting still. I know it isn't a big deal, it's just me. And I don't have a tach.

In order to turn the pot "up" while adjusting, should I back it down first (counter clockwise) before I start the engine, and then adjust it up (clockwise) to the proper setting?? I really don't want to mess it up.

Thanx guys,
Chaz

Chaz...you said "should I back it down first (counter clockwise) before I start the engine, and then adjust it up (clockwise) to the proper setting??".........exactly...I should have explain better....like you just did. Thank you. However make sure the regulator is 80 degree F before the adjustment and you don't have to do the "back it down" with engine off.

Caution...never rely on dash gauge and beside you need to have a digital meter near you to watch the changing while adjusting.

About RPM...always have it running faster then idle to adjust. Your high-idle could be OK if it RPM set right. Some are too low RPM.

The engine RPM will sound like 30 MPH before adjusting voltage regulator.

BTW..before any adjustment is being made...make sure all your ground connecting (including regulator) are good. No rust or corroded coating.

Sojourner · November 06, 2008, 11:42:50 AM

Sorry for the waste of post....MAK's board only have 1,239,452 posting left.....just kidding.

buswarrior · November 06, 2008, 07:13:58 PM

Chaz.

Stand on the throttle and let it scream.

The governor on the engine won't let you hurt it.

Really.

(There you go, an excuse to drink heavily before hand to work up the courage!)

happy coaching!
buswarrior

Chaz · November 07, 2008, 07:23:10 AM

Sojourner,

QuoteHowever make sure the regulator is 80 degree F before the adjustment and you don't have to do the "back it down" with engine off.

Thanx again. I'll follow your guidelines but, 80* nowadays may be tough to get to. Maybe it will get to that in the engine compartment if I let it run long enough. Hmmmmm.......
Other wise, from what I understand your saying, I will just have to back it down and then start it up.

I do use a digi VOM when adjusting. The estimates were just from the dash gage.
OH!!! By the way, when I was trying to adjust it the other day, there was 0 voltage drop if I ran wire from the battery or took it off the Pos terminal of the regulator. I thought that odd, but that really was the way it checked. I'll still probably go with the jumper wire to make sure.

Warrior,
I'll probably forgo the heavy drinking

so I don't screw up too bad! LOL
I don't have a high idle (seems the solenoid is backwards for some reason. Dallas was also confused) so I will just stick a screwdriver in the throttle. It just makes me a little nervous.

Thanx guys,
Chaz