Here is the scoop folks.
I went for a cruise tonight in the 52 Panel, 6V poss ground, 8BA. It kind of broke up a bit at the tail end of winding out 1st gear. It ran ok thru 2nd and 3rd. I went home and brought up the electric fuel pump pressure a bit, thinking I had it too low ( 7-8 lbs )and it was starving for fuel. I noticed the voltage regulator was pretty hot when I bumped it with my elbow while messing with fuel pump. I gave no more thought since the truck was sitting/running in my driveway for 5 minutes. I went back out for a ride,..its nite time and I got the lights on, and every once in a while it does the break up thing in 1st gear. I drove around town fot 40 minutes or so. I notice when I was a couple miles from home that my dash lights were a steady dim. Usually they are bright at higher rpm's and dim at low. I then noticed the head lights were not brighter with rpms and dim at low. I glanced at the charge Indicator and it was dead set in the middle,... not charging at +rpm's or discharging at low rpms. I got it home, shut it off,..and started it right up again. I shut it off, turned the headlights on and the charge indicator didnt move one way or the other.
Thats all I had time for. The voltage regulator looks to be original, battery is new not sure about age of generator. Any suggestions
Whoa! 7 - 8 psi will blow the float right out of a Holley carb. It is supposed to be 2 psi tops.
Check your voltage at idle and 1200 RPM, it sounds like the VR is shot all right. But it could be the gen too. There is a way to put the gen in "full generating" mode with a jumper, but I don't remember how. If you pull the cover on the VR, look for burned points or wires, broken solder, etc. If you remove the VR, look on the back, there are two wire-wound resistors that can smoke off -- it will be fairly obvious if they have.
Well, if it isn't Mr. John Smith Jr. We used to know a guy here by that name but after he got his truck running he stopped calling and writing.
Ok Mr. John....things come in threes. Yes it could be the regulator, but if it was, you should have showed a discharge with the truck off and the lights on, as you would have been supplying power to the lights from the battery, through the 15 amp breaker across the jumper to the 30 amp breaker to the light switch.
And if the truck is off and the lights are on, there isn't much of any way you can not show a slight discharge (or better - a jump of the needle when you turn the lights on). With your stock wiring and the signal flow path you have, if the lights are on and the generator is not turning that power HAS to be coming from the battery and the circuit from the battery to the lights (from the battery to the starter solenoid to the 15 amp breaker across the shunt to the 30 amp breaker out to the light switch down to the dimmer, out to the light bulb then to ground) HAS to be complete. But you may have impedence in the charge flow coming back with poor connections or shunt at the CBs. There's a 15 to 20 amp difference in the flows.
Hmmm funny thing, I recently recall hearing about some non charge and sputtering (actually quiting) things in a recent thread by Mr. Bob Jones called "Diagnosis Please"
With trucks that have sat for awhile, you run the risk of bringing them back to life with old wires that have had no juice in them, corroded contacts, etc. This again sounds like circuit breakers to me, if it's not the regulator. Just a note: your regulator is temperature sensative and performance will change with temperature differences. From a simplistic stand point, I'd probably change out the regulator and hope it fixes it. If it doesn't, read on:
Here is the link to Bobs thread, I'd check it out.
Also there is a way you can check your generator output by "bypassing" your regulator.
First disconnect your "Field" and "Arm" wires at the regulator. Connect a jumper between the field and Arm terminals on the generator. Connect the negative side of a 100 amp ammeter to the battery. Start the engine and immediately connect the smmeter positive lead to the battery. Run the engine at 1500 rpm. The generator output should read or exceed 35 amps on the meter.
If you want to cehck your regulator performance, the three circuit tests are discribed starting on page 257 (para c) of th eshop manual.
HA HA Julie ( alias SO CAL SPARKY ). I wish I was just cruising all the time. Things are dead in my hometown in my business so we picked up some nice work out of state and I am gone 6 days a week. Not complaining. Very grateful for work. Also, I was saving myself/calling and writing for the upcoming surge of updates I am hoping to do now that it warmer.You will be sick of me by August. I try to lend a hand on here once in a while, but you cant give away what you dont got,. Do you realise my, toasted from the 60's mind needs to read your post 3 to 4 times before the idea sinks in .
Thanks for the heads up on Bobs thread. What a tuitorial !! Also thanks to Ross. You guys are great.
I had to order some exaust stuff fom Joblot and and some stuff at DC so I added the VR to th list. I have not had time to do more messing around but I got a short week for a change this week and can crawl under dash and look at the CB's ect.
Thanks a bunch
Last edited by john smith jr; 05-17-2009 at 06:58 PM.
Reason: I am a crispy critter with spelling
That's funny about reading the post 3 or 4 times. But don't feel so all alone, everyone tells me they ahve to reead through my "disertations" a number of times to pick out everything.
Just trying to be thorough in my explanations - I'd hate to fry someones electrical system because I left something out. And also, I think it really helps if you Understand the system when you are trouble shooting it - so I try to give as much info as possible!
I removed my old V regulator. Nothing on the back looked fried, a few old bugs. Took off the cover and it looked good inside which surprised me since the cover was so rusted and beat. I put a new regulator on, polerized it, put on new 6V batt cables, cleaned up the terminals, mounting screws,applicable contact points, checked the BATT water, ect. and started it up. As I mentioned in my opening thread comment, my charge indicator and lights use to dim and brighten up quite noticeably at the respective RPM's speeds. I noticed those light intensity differences stopped. That prompted this thread. It was my supposition that these dim/bright changes were normal and the steady almost non existent light charge indications were a sign of a problem. Now with the new VR, there is slight movement in my charge indicator when I go from running lights to head lights. To be honest, I did not scrutinize the movement of the charge indicator last week, as I did tonight. It shows a bit more on the charge side when headlights are on. I turned off the truck, put on the head lights and there was a slight move in the charge indicator. The truck started up again with no problem.
Being a newbie I now ask..Is it possible that the dimming at low rpms and bright at high RPM was abnormal and what it changed to, and what I have now, is really closer to the normal operation??
It did breakup again tonight at the high rpm end of 1st and 2nd gears but I get the feeling thats unrelated to the VR. I think my fuel pressure regulator or the litlle pressure gauge is no good. I had adjusted the pressure to 3 psi and was trying to bump it to 4.5 psi but no matter how many times I turned the pressure adjustment , the gauge would not show a increase or decrease in pressure. It just hangs on 3 ish.
I will test the generator output this weekend. I did get a look at the circuit breakers and I didnt see ant scorching or funny stuff,.
Hook up a digital voltmeter and see what's really happening. If the charging system is working properly there should be about 6.9 to 7.2 volts at the battery with the engine running (not idling). A $10 to $20 cheap imported DMM is good enough.
OK Well I guess it's time to dash all those "there is nothing wrong with keeping the 6 volt electrical system, they are more than sufficient" arguments.
Here is a quote from the unsupplimented 49-51 Shop Manual - page 351 Para b:
"If the resistance (voltage drop) is equal to or less than specified in the test, the battery is low due to improper operation by the owner. Excessive night driving or use of accessories, insufficient operation of vehicle, accidental discharge of battery (lights, ignition, radio, etc. left on overnight) improper starting procedure (flooding engine, not using choke properly, etc), or too heavy a grade of motor oil for the local climate could take more current from the battery than the generator can replace. Instruct the owner in proper operation of his vehicle."
Wrong grade of oil??????? Too much night driving???????
I think you can see by this statement that the original system is somewhat "finicky" given certain very minor variables. I would imagine that changing out the regulator and cleaning all the contacts, let alone improving the regulator grounding by just moving it around, probably all added a "dash of health" to the charging system.
I don't think it was acting abnormally either before or after (notwithstanding the regulator dying) just older and newer.
Hey if you continue to have charging problems, change the oil!
That is certainly a case to speed up the 6 to 12 V conversion Julie. I also read on page 350 " BATTERY LOW CHARGE,...Indications pointing to this symptom are: slow cranking, hard starting ( not a problem here, however, the next line) HEADLIGHTS DIM AT IDLE SPEED....was what was the "norm" for this truck was prior. So, according to the HOLY SHOP MANUAL my past dimming situation was an indication of a battery low in charge. So,.. can one conclude that the present absence of that symtom is an indication of normal operation? The only past problems I have had with starting this old boy have been fuel/ carb related. It has flooded and I cranked it a bit to get it started but not a regular thing.
I am going to do the GEN output test and the quick check ANGUS mentioned.
I got some extra cash so maybe I will get the parts together to do the 12V upgrade. If nothing else, this has got me back in the swing of tinkering after the winter blahs. Tinkering always seems leads to good improvements.
You are absolutely correct - low battery charge. But, what caused it - generator going bad (doubtful) Old regulator suddenly brought back to life and not handling it too well after some use (probably), dirty contacts or older battery cables(most probably).
When you have a charging system that is this marginal in providing for the stock vehicle needs (ie the wrong engine oil could trip the tables on sufficient charge) it could be most anything.
On these systems, the battery acts as a peripheral - a pool if you will - to provide power to turn the starter and extra amps if the generator won't keep up. That's why if your battery is low in charge, it can't help the struggling generator keep the lights bright.
Angus' test is correct in theory, but checking voltage is an indicator of SYSTEM function, not COMPONENT function. IOW if you check voltage and it is in the range he specified, it says the charging system is on line. But it doesn't tell you if it is on line correctly or if not on line what is wrong.
The shop manual has a VERY simple test for checking generator output - in amps - which is the important factor, not voltage. I think I quoted it above toward the end of post #3. If the generator is putting out amps then the only problems you have if your battery is low, is the regulator, the shunt between the circuit breakers, dirty old connections, or bad battery.
The tests are pretty straight forward. If the generator test passes and all your connections and cables are good, I'd just replace the regulator at that point considering your battery is new.
The actual tests (non trouble shooting) start on page 249, and are pretty straight forward. If it gets to be too much write me a note at the real e-mail, and I'll recommend a summer grade of motor oil!
How did I know that was coming Julie Coolie......Ok OK OK OK!!!!
I dont suppose "Bolt Right up" in the Tuff Stuff link means it will work with the stock flattie GEN mount?
I will try to send the 6V VR back and put the old one back in so I can feed the urge to cruise untill I gather the 12 conversion stuff.
Let me settle in for a holiday weekend 12V conversion thread study-rama.
Oh I wouldn't do that, just put the 6V regulator on and enjoy the truck for the rest of the summer. Then when it starts getting undrivalbe back there we can do the rewire - I'LL HELP!!!!!!!
See here's where this goes - if you drive at night, and run a heater (defroster) You are screwed - worse if you get electric wipers. You see how it is.
But for the summer, your fine. Hey do this. When you drive at night and get home, turn the lights and all the electrical stuff off, then run the engine at about 1500rpm for two minutes to give the batttery one last kiss goodnight! Might be all the diff you need.
Ya know on my 55 it used to do this and I wired in a switch that when thrown would bypass the voltage regulator and pump about 30 amps into the battery for a quick charge. It saved my life a few times on long trips pulling into gas stations at night. But I'm not going to tell you how to do it.....you can blow up a battery if you arent carefull.