Your donations help keep this valuable resource free and growing. Thank you.
|
Motorola with no voltage regulator |
Post Reply | Page 123> |
Author | |
pacerman
Supporter of TheAMCForum Joined: Jul/03/2007 Location: United States Status: Offline Points: 9057 |
Post Options
Thanks(0)
Posted: Dec/16/2017 at 8:32pm |
Text Deleted. We found the regulator moved to the firewall behind the V8 engine. I will have other questions though. Joe
Edited by pacerman - Dec/17/2017 at 2:03pm |
|
Happiness is making something out of nothing.
|
|
tomj
AMC Addicted Joined: Jan/27/2010 Location: earth Status: Offline Points: 7544 |
Post Options
Thanks(0)
|
absolutely, 17.5V for even brief periods is going to stress everything electronic or filamentary, done and done. dont run it! bad shop... if they weren't sure they should have checked at a minimum with a voltmeter.
unlike generators, alternators generally require some low-current "tickling" to produce an initial magnetic field that generates power from spinning that in turn produces the current to self-power it. there may be sufficient residual magnetism to start, but not enough for OEMs to rely on so they use some start up current, usually the dashboard idiot light (plus resistors int he harness, etc) if this is a stock harness though it's not capable of handling the 50, 75, 80 etc amperes from a large GM alternator. stock, there should be wires etc for the regulator for what you've got. |
|
1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5 http://www.ramblerLore.com |
|
pacerman
Supporter of TheAMCForum Joined: Jul/03/2007 Location: United States Status: Offline Points: 9057 |
Post Options
Thanks(0)
|
Ok we found the voltage regulator behind the engine. Voltage with the engine running is 17.5 voltages. We were working under the dash but only with the circuits powering the gauges (actually new VDO gauges) and do not think we changed anything regarding how the voltage regulator would sense voltage. We are thinking the solid state voltage regulator took a dump. Is there any way to test it before we opt for a new one?
Thoughts? Joe
|
|
Happiness is making something out of nothing.
|
|
Bruce Clarkson
AMC Addicted Joined: Feb/09/2013 Location: New Bern, NC Status: Offline Points: 538 |
Post Options
Thanks(0)
|
My limited experience is that if you have correct connections between the alternator and regulator and are getting over voltage the regulator is messed up.
I've also had the painful experience that about zero seconds running with a flakey around to the alternator Will kill a regulator. Not sure completely why. Note that the regulator is not grounded via it's case. My electrical rebuilder can better test the combination of the alternator and regulator is I bring in both. (Normally he's just concerned with the alternator.) Yours probably can too maybe. Good luck, Bruce Clarkson
|
|
Bruce Clarkson
|
|
billd
Moderator Group Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894 |
Post Options
Thanks(0)
|
You can test only certain things.......... otherwise it's all in the wiring. If the wiring is fine and you've triple-checked that part, then it's regulator.
The regulator DOES NOT GROUND TO THE CHASSIS!!!!!!!!!!!!!!!!!!!!!!!!!! The regulator grounds ONLY via the black wire to the alternator so that must be perfect. Case in point, I was testing my bread-board regulator circuit today (I'm developing new "guts" I can put into original Motorola housings) and a ground came loose and the voltage shot up to 17.5 volts. The ground was connected but loose, meaning the regulator was "sensing" a lower voltage due to the large voltage drop across the bad ground connection. Alternator rotors are treated to NOT hold magnetism. Many will self-start once they hit about 1500 to 2000 engine RPM....... but don't count on it. As I've told folks before - if they want me to work on the alternator and want to be very certain both alternator and regulator are ok and work together, send me both. I can check both. I've posted proper regulated voltage here - which regulator is set to regulate at what voltage. I may be mistaken, but I thought the Prestolite regulator was mounted on the firewall - I've seen some AMC harnesses with connections back there that appear to be regulator connections................. I have also posted what regulators work with which alternators - and the warnings about mixing them up. For example if you use an R2AM1, R2AM2, or R2AM4 regulator with a 1971 and later alternator (with NO isolation diode) you will over-charge by about a volt. If you use one of the 8RB2005 or 2003 regulators with an alternator using an isolation diode, it will UNDER-charge by a volt. Again - orange wire from dash ALT light goes to alternator and regulator. This excites the field and controls the light. Yellow from ignition feed is a backup field excitation - in case the bulb is burned out the yellow will excite the field to get it charging. Black is critical - from regulator to alternator, direct path, no stopping or connecting to anything else. Green is also direct from regulator to alternator for the field. If this is loose you'll not get enough field current and it won't charge enough, or at all. Once the alternator starts to charge, the current for the field comes from the regulator terminal on the alternator......... NEVER EVER EVER EVER disconnect the battery when the engine is running, PERIOD. This doesn't show my whole test setup, there's other equipment involved, but here I'm testing a home-designed/home built regulator on a running alternator. I just got it working today............. hopefully to be able to rebuild old regulators using the original regulator housings....... It's in rough bread-board stage but it WORKED. I need to make a change or two as it regulated a tad high but that's a simple change or two. |
|
amx007
Supporter of TheAMCForum Joined: Dec/31/2008 Location: stone pk Status: Offline Points: 750 |
Post Options
Thanks(0)
|
Need help local 60165 I took car amx to hack he cut up my wires from alternator to regulator all it was he did not have bottom power plug plugged in now I have a birds nest sucks
|
|
dream red white and blue
1968 Chicago auto show amx 290 4 speed 1969 driver Amx 290 auto |
|
billd
Moderator Group Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894 |
Post Options
Thanks(0)
|
The wiring is really pretty simple............ there was a fellow here who had a different alternator on his car and wanted to put it back to original but the regulator to alternator wiring was missing, it had been cut out so he didn't have any of the regulator connection, etc.
I made a sub-harness for him with the correct connections and all he had to do was connect it to a couple of wires in his harness and he was back to original system. The green wire to field and the black to ground are simply from regulator to alternator. The yellow goes from ignition feed to regulator, that was one connection he made, and the orange comes from dash ALT light to regulator, then down to alternator. So he had to make that connection as well. That was number two connection. His was a 1970 so the black ground was in the same connector as the green field wire, otherwise they were pretty much the same as 68 or 69. The yellow shown here has a connector for the coil, and the other end of the yellow needed to be connected at the I terminal of the starter solenoid. The orange needed to be connected to the harness orange with tracer which comes from the dash ALT light. It's really that simple. [
|
|
amx007
Supporter of TheAMCForum Joined: Dec/31/2008 Location: stone pk Status: Offline Points: 750 |
Post Options
Thanks(0)
|
Thank you
|
|
dream red white and blue
1968 Chicago auto show amx 290 4 speed 1969 driver Amx 290 auto |
|
billd
Moderator Group Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894 |
Post Options
Thanks(0)
|
The basics -
From regulator plug to alternator, direct, no other connections: Black from regulator plug to alternator - it's grounded on a stud on the back of the alternator Green from regulator plug to alternator field/brush spade (flat connector sticking straight back) From the car's harness to the regulator: Yellow from ignition feed to regulator plug Orange with trace in car's harness under the hood goes to the regulator plug, then back out and to a connection on the alternator back side. Knowing the model number of your alternator, or just if it's a 35 amp or a 55 amp, we can get totally specific and show exact connections on the back of the alternator. |
|
tomj
AMC Addicted Joined: Jan/27/2010 Location: earth Status: Offline Points: 7544 |
Post Options
Thanks(0)
|
oh nice! didn't know you were such a hardcore nerd! cool! what changes/improvements are you going for here? (other than the precision i know you know and talk about). maybe adjustable? (trimpot on the back?) |
|
1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5 http://www.ramblerLore.com |
|
Post Reply | Page 123> |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |