2nd Gen Non-Engine/Transmission Low voltage readings

[bnbrown]

I had a problem last weekend that the batteries went dead after sitting for one full day, it was cool, about 50 degrees out, I figured one of the batteries went bad, so replaced them both (they were only 8 months old, so got a new set for free), the volt meter had only showed low volt once before, after a long run (20 hours nonstop) and sitting two days, but started that time, and showed 14 volts after 10-15 seconds. After replacing the batteries it looked ok for a day or to, mostly daytime hiway driving, but now it is only showing maybe 12 volts going down the hiway, once in a while it will creep back up to 14 then slump back to 12, not the sharp change like when the grid heaters are cycling. wondering if maybe my alternator is going, or if i got a bad batt. will try to have the batts and alt load tested. Hooked the batteriesto a charger, still in the truck and hooked up, only drew 5 amps (charging both at once) for a few hours then down to 1 amp, where it stays, so apparently the batteries are charged... any ideas? it is a possibility that the alt. has been compromised, it has been sprayed with plenty of engine oil from leaky breather before i moved it, and later by coolant from leaky head gasket.

thanks for any thoughts.

 

[crabman]

bnb,

Electrical problems will drive you nuts!

Be sure that all battery connections are clean and tight. Check negative battery grounds to engine also. I would have the alt. bench checked first, then you know that the batteries & alt are good.

Does the tach work? Cruise control work? Did you check the large fuse in the PDC box (120amp)?

Check the engine speed sensor connector,take apart the connector, clean & put some dielectric grease on it and reinsert.

Try this and see what happens. If nothing works, post again.

Do you have a manual?

crabman

 

[crabman]

bnb,

Electrical problems will drive you nuts!

Be sure that all battery connections are clean and tight. Check negative battery grounds to engine also. I would have the alt. bench checked first, then you know that the batteries & alt are good.

Does the tach work? Cruise control work? Did you check the large fuse in the PDC box (120amp)?

Check the engine speed sensor connector,take apart the connector, clean & put some dielectric grease on it and reinsert.

Try this and see what happens. If nothing works, post again.

Do you have a manual?

crabman

 

[bnbrown]

Thanks for the ideas, I removed all the connections, cleaned and reattached, all systems work normal, throtle response, tach, 120 amp fuse ohms good, swapped around a couple of the relays to make sure it wasnt something sticking on, took it to autozone and had them hook up their load tester and tested each batt. individually, both tested perfect. put an amp meter on the (+) lead from the right side batt, and checked the charge/discharge @ 2K rpm, volts were never over, so the regulator seems to be OK, but when the volts would start to drop, the amps were in the -10 range, then amps would go back to charge at up to 50 or so... and volts would go back up to 14..... looks like the alt. is shot, its the denso 136 amp one, so had to special order, but should have it by tomorrow afternoon, hopefully that should do the trick. need to do some rewiring anyhow, have too many toys on there now, looks like one of the telephone service boxes on my (+) batt terminal time to clean it up a little under there.

 

[bnbrown]

as far as a manual, I have the Chilton, 1 book fits all, better hope you already know what you are doing guide to automotive disrepair

 

[crabman]

Manuals

bnb,

Try this site for a factory manual. www.techauthority.com

I have a factory manual, a(94-95) Powertrain Diagnostic Procedures manual for Cummins diesel trucks, a B series shop manual, a 6BT5. 9 parts catalog and I also have a Haynes manual (good pictures). Can't have to much info!!!

But I still am/get on alot of things!

I am in the process of looking for a good DRB($$) to help in some of the problems that arise. Besides, you can NEVER have to many tools!! :-laf

crabman

 

[WestTN]

If oil got into the alternator the brushes may be fouled or worn out. this could cause intermittent charging until they fail completely.

 

[bnbrown]

Thanks for the input, picked up the new alt, stuck it in and it seems to be right back at normal again. Even with the batts a little low (maybe an hour of run time with no alt. helping while i went and picked up the new one) as soon as i fired 'er up with the new alt in there it climbed right to 14 volts at idle and stayed there like it should. I do need to get a better manual, most things are pretty straight forward, and atleast the chilton guide gives the major warnings if there is something that must be done in an order, or marked before removal. This ole girl never really gave me any problems till I hit about 130K miles... needing a few of the "consumables" replaced now at 150K, power steering pump is startin to take that long walk off a short plank, but think I can limp that along a while longer, till christmas anyhow when i will have another vehicle to drive while I get that fixed, and the steering gearbox leaks like a sieve. bolts on the cover plate seem to loosen up over a month or so, and let it leak like crazy on tight left turns, or turning at stopped or slow speeds on course pavement. wouldnt trade it for anything though, nice to know that you are going to get where you are going, just might not have power steering/brakes when you get there Owning a dodge gasser, a ford 6. 9, and a chevy gasser before sure does make me appreciate what i have