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68 442 convertible. 455 HEI. A little back history: Installed a new engine over the winter and went to start it up a couple weeks back. No spark. Found it to be the module in the distributer. Changed it out and did my break in for the motor. I was mucking around with the Neg battery terminal and pulled the wire out of the terminal. It had broken at the point of connection but could not be seen. I assumed it was my issue with e module. After replacing the cable it seemed ok for a day or two but I was checking my voltage yesterday. 16 v when running. no GEN light at first but its on now. It will go out when i rev the engine but comes back on when idling. I went over my whole charging system and could not find the issue. Installed a known good battery. I have 12.77v at the bat. 12.77 at the relay stud. 12.76 at the #3 wire to the regulator, 0 at the other wires. When I turn the key on, I only get 11.7 on terminal #4. not sure that means much. When I jump # 3 wire to F the voltage goes up as it should. No spiking or growling. Jumped #3 wire F wire with volt meter hooked to #2 and got 9 -10 volts. Also checked continuity on th F and #1 wires and they look good. Ill take that with a grain of salt though. I also bypassed these wires when testing to be sure they are not the issue. Also jumped a ground wire to regulator with no improvement. Next I swapped out the Reg and Alt with the same results So I'm at a point here where to look next. Any help would be appreciated. Thanks in advance , Greg
I also want to add after changing the alt and reg I have 12.5 v on the battery when running. This rises when revving the engine. It goes up and up and up.
If you only have 12.5 VDC at the battery with the engine idling then either the alternator or voltage regulator is bad. You can remove both and have them tested at the auto parts store. You can also drive your car to the auto parts store and have the alternator tested on the car.
You should see about 14.2 VDC at the battery with the engine idling.
Olds64, Thanks for the reply. I had a regulator and Alt. on hand so tried swapping them out. Same condition. They were still under warranty with Nappa so they gave me new ones. Not the crappy made in China but good quality made in USA. Tried them this AM. No luck. I'll just keep going over the system and reading the manual. My plan was New harnesses this winter as wiring has been mucked with too much for me to feel good about it. concentrating on the field/relay wires now. Driving the car now is not an option as the battery over charges. Please let me know if I should look into anything else. Greg
I noticed that my fuse panel is loose on the fire wall. It wiggles a bit when pulling on wires.
A few pics. Maybe somebody will see something I do not. I disconnected the wipers and electric choke to rule out possible issues. The clear tube is for checking vac. an manifold.
I was showing 16 volts when I first noticed the issue. I put in a different one for testing and I'm not letting over charge. The higher voltage was after driving the car to my shop. # 3 wire has been showing Bat voltage and changes with state o charge. That being said i did not check that at that time.
Is this an over or under voltage condition? In the second post you mentioned that the new alternator and voltage regulator only charge at 12.5 V. Did you swap anymore components after that?
Over voltage. At idle I get 12.5 at the bat with car running (low) but when I pick up the RPM or drive the car the voltage goes up and the battery over charges. I tried a second new alt/ reg. this morning and no change.
At idle w/ no accessories &/or devices operating measure voltage at battery.
At idle, turn on headlamps &/or A/C & heater measure voltage at battery.
Record any variance in voltage across battery terminals.
At 2,000RPM w/ no accessories &/or devices operating measure voltage at battery.
At 2,000RPM, turn on headlamps &/or A/C & heater measure voltage at battery.
Record any variance in voltage across battery terminals.
I'll note you have several areas depicting modified wiring. Suggest you remove any extraneous wires not attendant to the original OEM wiring diagram & incorporate ONLY required wiring - especially those which feed off the Horn Relay Distribution Post. Disassemble/Separate each of the wires, trace & correctly label each wire. Get back/down to basic wiring schematic. Oldsmobile did not use those crappy yellow crimp/splice connectors I see running between the + battery terminal to the Horn Relay Distribution Post - especially two crappy yellow crimp/splice connectors within about 12" from one another. Suggestion (again), get the wiring back/down to the basic wiring schematic with proper wiring & labeling.
OK, @ idle, 12.8 this time Lights on @ idle 12.25. 2000 rpm ish15v and continued to rise. I turned on lights and 12.5 steady. I am going to bring up that I had no low beams prior to this and was in the process of looking into it when this all came up and I did not mention it. The low beams are working all of a sudden. The plot thickens.
OK, @ idle, 12.8 this time Lights on @ idle 12.25. 2000 rpm ish15v and continued to rise. I turned on lights and 12.5 steady. I am going to bring up that I had no low beams prior to this and was in the process of looking into it when this all came up and I did not mention it. The low beams are working all of a sudden. The plot thickens.
Can't recall but I think you said you have the 1968 CSM w/ attendant wiring diagram. I believe in 1968 the 442 wiring was identical to all other Cutlass vehicles. You should realize you'll be far & away much better served in you employ the correct wire gauge for each & every wire w/o a bunch of crappy spliced crimped connectors & terminal ends. Best to use ONE length of wire of appropriate gauge matching the wiring diagram. Best to solder your wire connections, terminals & always use rubber shielding/insulation. Might be a good/worthy time to upgrade your wiring tools. At any rate, in case you're lacking a readable 1968 wiring diagram....
It would be worthwhile to evaluate the battery. A bad battery can easily succumb to an overcharging condition even when it reads 12.6VDC. Isolate the battery from the car (remove) when possible. Charge battery to optimal state of charge - a new battery should easily be able to retain a charge between 12.6VDC to ~13VDC overnight. Monitor the battery closely as you evaluate its state of charge. The date on the battery is one piece of the puzzle; yet, with continued battery overcharging (which you may have experienced for a lengthy period of time), it becomes a crap-shoot if the battery has weakened. Continuous monitoring of the isolated battery state of charge (e.g. on the bench) can provide clues. Overcharging easily contributes to an early battery death.
I was showing 16 volts when I first noticed the issue. I put in a different one for testing and I'm not letting over charge. The higher voltage was after driving the car to my shop. # 3 wire has been showing Bat voltage and changes with state o charge. That being said i did not check that at that time.
I'm sorry, but does this mean voltage at #3 is also 16 volts when battery is reading 16v, or does it mean it hasn't been tested yet.
Norm, Agreed. I will go over all my under hood wiring again one wire at a time. Under the dash is a mess of wires, after market radio with 6 speakers in the doors alone. Wires everywhere. It seems I should see what's going on with the lights before moving on. I was only able to look at the continuity of the Hi Low floor switch before being pulled away. Could not find an issue with it. What could cause a no low beam situation?
Stellar. Sorry, I did not check this before installing a different Battery at normal charge. All other readings at #3 wire showed Battery voltage. Greg
Norm, Agreed. I will go over all my under hood wiring again one wire at a time. Under the dash is a mess of wires, after market radio with 6 speakers in the doors alone. Wires everywhere. It seems I should see what's going on with the lights before moving on. I was only able to look at the continuity of the Hi Low floor switch before being pulled away. Could not find an issue with it. What could cause a no low beam situation?
Likely several factors. However, in general the likely suspects w/ the greatest majority of electrical issues stems from the ground wire side of circuitry. They're easily addressed in most cases but take time to evaluate. All negative ground vehicles must have a solid ground circuit path which allows electrons to flow from the negative (-) anode DC battery terminal throughoutthe entire vehicle returning to the positive (+) cathode DC battery terminal. Attenuation & impedance of electron flow is by far the greatest issue(s). Ensure your ground straps/wires, their terminals & the metal surface(s) these wires connect to are free from corrosion & oxidation (e.g. rust). Remove the terminals, wire brush, sand paper your grounds wherever you find them but begin with the battery negative (-) terminal cable to the engine block as your primary ground source. Next, check ground wire(s) to vehicle chassis, & any ground wire from engine head to firewall. The VR gains its ground from the firewall. Remove, inspect, each of these points for corrosion/oxidation (rust), etc. A solid ground is paramount to a good charging system.
It would be worthwhile to evaluate the battery. A bad battery can easily succumb to an overcharging condition even when it reads 12.6VDC. Isolate the battery from the car (remove) when possible. Charge battery to optimal state of charge - a new battery should easily be able to retain a charge between 12.6VDC to ~13VDC overnight. Monitor the battery closely as you evaluate its state of charge. The date on the battery is one piece of the puzzle; yet, with continued battery overcharging (which you may have experienced for a lengthy period of time), it becomes a crap-shoot if the battery has weakened. Continuous monitoring of the isolated battery state of charge (e.g. on the bench) can provide clues. Overcharging easily contributes to an early battery death.
Thanks for the info Norm I did change out the overcharged battery with a known good Battery 12.8 v before doing tests
Likely several factors. However, in general the likely suspects w/ the greatest majority of electrical issues stems from the ground wire side of circuitry. They're easily addressed in most cases but take time to evaluate. All negative ground vehicles must have a solid ground circuit path which allows electrons to flow from the negative (-) anode DC battery terminal throughoutthe entire vehicle returning to the positive (+) cathode DC battery terminal. Attenuation & impedance of electron flow is by far the greatest issue(s). Ensure your ground straps/wires, their terminals & the metal surface(s) these wires connect to are free from corrosion & oxidation (e.g. rust). Remove the terminals, wire brush, sand paper your grounds wherever you find them but begin with the battery negative (-) terminal cable to the engine block as your primary ground source. Next, check ground wire(s) to vehicle chassis, & any ground wire from engine head to firewall. The VR gains its ground from the firewall. Remove, inspect, each of these points for corrosion/oxidation (rust), etc. A solid ground is paramount to a good charging system.
When pulling the old motor and cleaning the engine bay I spent a lot of time making clean grounds, Taping off clean metal before painting and making sure all fittings were tight when done. I will check them again as i am not always perfect.
Not sure on the 1968 442/Cutlass there may be a engine head to firewall ground strap which is vitally important since your firewall requires a ground. This ground then becomes the ground circuit for your VR & dash panel. I'll see if I can find a ground strap diagram for a 1968.
Sorry, I don't have the 1968 PIM (Product Information Manual) equally sorry for the quality of my 1969 PIM image. It's likely 1968 has the same ground strap to firewall ground strap as 1969. Others following may be able to confirm. One, ensure you have this ground strap; two, ensure it's in good condition free from rust, corrosion, oxidation. I think you already did an R&R of the VR, ensure the attachment of the VR onto the firewall is free of corrosion, as well.
Sorry, I don't have the 1968 PIM (Product Information Manual) equally sorry for the quality of my 1969 PIM image. It's likely 1968 has the same ground strap to firewall ground strap as 1969. Others following may be able to confirm. One, ensure you have this ground strap; two, ensure it's in good condition free from rust, corrosion, oxidation. I think you already did an R&R of the VR, ensure the attachment of the VR onto the firewall is free of corrosion, as well.
just behind tranny dip stick
as far as the butt connections they hold the fusible link, they came with the car. Not crazy about them myself and will get soldered when there is time. seriously thinking new harnesses this winter
This may be the problem. Pulled the harness out of the regulator and it fell off. I must have pulled and cleaned this thing 3-4 times. Still did not get it real clean. I'm pulling the wires and terminals now to check the rest. Thanks for all the replies. It helps to keep the gears in my head spinning when i start to get discouraged.. New wiring harness is needed, some of the wires are getting old / stiff and I don't want to be doing this again next year. Greg
...as far as the butt connections they hold the fusible link, they came with the car. Not crazy about them myself and will get soldered when there is time. seriously thinking new harnesses this winter
Bear in mind the fusible link (wire) runs from the post located on the Horn Relay Distribution Block to one (ONLY) single crimp connector. The fusible link should be four (4) wire sizes smaller than the wire it is protecting; i.e. use 14AWG fusible link to protect a 10AWG wire. Note in the 1968 wiring diagram the red (protected) wire is 12AWG; therefore, the fusible link (wire) should be sized at 16AWG and be one continuous wire w/ no additional crimp connectors - one crimp connector between the protected 12AWG wire & the 16AWG fusible link wire. Additionally, use only fusible link wire manufactured to specifications for a fusible link - do not use regular automotive AWG wire. Fusible link wire is NOT copper wire, it is a special low melting point metal alloy (conductor) wire encased in protective high-temperature fire resistant insulation, generally Hypalon®, a strong cross-linked polyethylene casing capable of retarding/suppressing sparks & flames. It would be in your best interest to ensure the single fusible link wire is correctly installed.
You can purchase fusible link wire at most automotive stores & elsewhere.
The below (1971 A-Body wiring diagram) image illustrates a 16AWG fusible link (black wire) connected to one single OEM crimp connector protecting a 12AWG red wire. The 1968 A-Body OEM fusible link wire was colored red. Beginning in 1969 the fusible link wire color was changed to black for A-Body vehicles; albeit, the black fusible link wire in this image.
Thanks Norm, I was not aware of the one connector requirement. Is that a certain connector in your picture? I have not seen one like it before. I just as soon solder in place if feasible. Very help full info. The link on the car now has a "fusible link" tag on it . I would imagine it would need to be a certain length? As far as my issues I am still looking for the source. Moving forward with all suggestions in mind. My low beams are not working again so i'll be on that today. Going to re group and start the charging circuit fresh. New fusible link coming tomorrow. Thank you for your input. Greg
There are various types of fusible links & attendant fusible link connectors. The connector (clear tube style) displayed in the image (above) happens to be what Oldsmobile used at least in the 1971 CS & several others. You want one connector between the fusible link wire & the wire the fusible link is protecting. A little research you'll find one which is appropriate. Here is one type...
So, To drag this thread out a little more... Norm Thanks for the link to C A auto. I,ll be looking for terminals for the Reg. Are they the Packard 56 type? I took your advise and starting to clean up that mess. Also found another fusible link under the tape in the correct location. It has been kinked badly so I'll get it replaced. Do you think I should replace the one coming off the Battery also or just go straight wire to the horn relay?. I think it was installed with the radio by P.O. Thanks for making me just do it. Greg
How about that. You found the original fusible link. Note the routing of the red 12AWG wire(s) the fusible link is protecting. You only need the one OEM fusible link as demonstrated in the 1968 wiring diagram. Again, be mindful of the protection it creates in that "circuit" - that's all you need. Each ancillary device e.g. i.e. etc. radio, high-wattage power amplifier, CB (Citizens Band) radio, should have a single correctly sized in-line fuse. Keep the single fusible link protecting the starter, IGN, BATT circuit (red 12AWG wires) off the horn relay junction/distribution block/post & you'll be fine. Good on you for unraveling the wires. Remove wiring you have no intention on using. Label wires as you move forward. Create good splices, solder, good connectors & please use rubber jacket insulation. Not such a bad idea to grab a roll or two of plastic split wire loom tubing & some black zip ties, but that's just my preference.
Nice ring but take it off when working on the car. Especially electrical stuff. I've seen some ugly stuff when guys where jewelry when working on cars. Mostly from rings and watches.
Good morning CO. I'll be waiting for my new harness for the next 3-4 weeks. Never wanting to stay idle on the car for too long I went to the storage trailer and found the harness for my 69. The wires to the headlights were not pretty but the alt / reg wires and terminals are in very good condition. So I installed into the 68. I needed to do 3 connections, all soldered and shrink wrapped. I also took out any crimps/ old splices and re soldered. Most of these were at the horn relay. Also replaced the fusible link and installed a correct alt plug. Took apart all grounds under the hood and made sure they were clean and tight. When checking bat. with engine at idle volts started at 12.7 and rose to 15 + volts. I shut down before it went any higher. It seems this is what the issue was when this all started..... Please let me know what you think. Or where to look next. I know it looks like a grounding issue but not sure where to proceed. Greg
