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I took that ground off because it just went to one of the radiator mounts which isn’t the chassis right. And like I said I don’t have a drill to make a hole
Chris (I assume) do you have a volt meter? While the car is running, measure the voltage of the battery - again, while the car is running. A good voltage being applied to recharge the battery on a 12V electrical circuit you can expect to see roughly 14.3V (DC) for a good GEN/ALT. Maybe a buddy has one you can borrow or at the least have the shop measure the voltage output of the GEN. Good Luck!
I took that ground off because it just went to one of the radiator mounts which isn’t the chassis right. And like I said I don’t have a drill to make a hole
Well, I'll leave that call up to you. I think you "might" have found the chassis ground; again, not exactly sure where the grounds are located on your beast. None-the-less, with that said, whoever hooked up that ground wire to the battery tray was most likely attempting to secure a good ground but the battery tray is NOT the place to hook up that wire. What you can do with that wire (or another wire) is to secure that ground wire to any nut/bolt located on the chassis. There is no reason to drill a hole. You only need to secure that wire to the chassis which is most likely why the wire is there but was installed in a bad location. That wire can also get attached directly to the negative (-) terminal on the battery since that where the car obtains its ground connection.
Chris (I assume) do you have a volt meter? While the car is running, measure the voltage of the battery - again, while the car is running. A good voltage being applied to recharge the battery on a 12V electrical circuit you can expect to see roughly 14.3V (DC) for a good GEN/ALT. Maybe a buddy has one you can borrow or at the least have the shop measure the voltage output of the GEN. Good Luck!
I do have one and that’s all I know how to use it for and when I’ve tested it, it’s at close to 14 which doesn’t surprise me with all the old wires on the car. I’ll check again in a bit, now my junk yard battery is going bad, they usually last me a few months and then they die.
Regarding the chassis ground wire. As vehicles evolved and the electrical circuitry evolved, there became a need to ensure the various grounds provided solid continuity for all the electrical devices; again, the ground circuit is "key". I've provided a diagram of a 1971 Cutlass (which is essentially same for all vehicles). The red arrow(s) demonstrates how the ground wire to the chassis is routed on all cars. It is a separate/dedicated wire from the battery negative (-) terminal post to the side of the radiator shroud housing.
Well, I'll leave that call up to you. I think you "might" have found the chassis ground; again, not exactly sure where the grounds are located on your beast. None-the-less, with that said, whoever hooked up that ground wire to the battery tray was most likely attempting to secure a good ground but the battery tray is NOT the place to hook up that wire. What you can do with that wire (or another wire) is to secure that ground wire to any nut/bolt located on the chassis. There is no reason to drill a hole. You only need to secure that wire to the chassis which is most likely why the wire is there but was installed in a bad location. That wire can also get attached directly to the negative (-) terminal on the battery since that where the car obtains its ground connection.
this may sound dumb but the chassis is the whole frame of the car correct? Like where you’d put a jack to lift it. Ok I’ll see where I can find a place for it
To demonstrate the additional importance of the ground circuitry and how it has evolved in various makes & models, there is a braided ground strap from the back of the head of the engine which is secured to a vehicle's firewall. This then becomes a solid dedicated ground to the metal firewall so all electrical devices secured to the firewall receive a proper dedicated ground. Easy to understand this since the battery negative (-) cable goes directly to the block of the engine. The head of the engine sits on the block of the engine. Therefore, using the head of the engine allows ground continuity to occur to the metal firewall using that braided ground strap.
To demonstrate the additional importance of the ground circuitry and how it has evolved in various makes & models, there is a braided ground strap from the back of the head of the engine which is secured to a vehicle's firewall. This then becomes a solid dedicated ground to the metal firewall so all electrical devices secured to the firewall receive a proper dedicated ground. Easy to understand this since the battery negative (-) cable goes directly to the block of the engine. The head of the engine sits on the block of the engine. Therefore, using the head of the engine allows ground continuity to occur to the metal firewall using that braided ground strap.
ok yeah I have that firewall one but I don’t think I’ve ever seen one going to the chassis but I’ll look again
The 1st diagram demonstrates a braided ground strap from the engine head to the firewall. NOTE: It isn't by chance they picked the screw holding the VR to the firewall to be the point of attachment of that braided ground strap - the VR needs a solid ground & this helps to ensure it gets just that. The 2nd diagram is simply (another) side view depicting the chassis ground wire from the battery negative (-) terminal to the radiator shroud chassis housing. These (obviously) are not a '55 Oldsmobile but they demonstrate the ground circuitry.
The 1st diagram demonstrates a braided ground strap from the engine head to the firewall. NOTE: It isn't by chance they picked the screw holding the VR to the firewall to be the point of attachment of that braided ground strap - the VR needs a solid ground & this helps to ensure it gets just that. The 2nd diagram is simply (another) side view depicting the chassis ground wire from the battery negative (-) terminal to the radiator shroud chassis housing. These (obviously) are not a '55 Oldsmobile but they demonstrate the ground circuitry.
ok awesome thank you for that help! As far as I can see I have the two grounds beside the battery one. One to the firewall and one to the radiator bolt. I’ll have to get another braided ground and find some where to put it
To the OP, I am glad you replaced the vr and the generator is now working.
This was suggested to you the first of the month on another thread where you inquired about your smoking generator. You certainly go about things the hard way. Anyway, glad things work now. Happy Motoring!
Super88, I have a 55. Let me walk you through the grounds.
1. In your first picture, the bolt on front of the block, is where the braided strap should attach. It is quite long, there is a hole in the middle of the strap that attaches to the battery tray. Then the strap continues up to the negative terminal of the battery. This part is available from Fusick. Depending on your current battery/post location, the braided strap may be a bit short.
2. Then there is another ground on the rt rear of the engine block that attaches to the firewall right by the block attach bolt. This is a secondary ground. As Vintage mentioned, the battery tray is not the best ground because there is usually so much corrosion around the battery tray. So, this may be enough ground to run the generator. Again, Vintage is correct, many charging problems are because of corrosion. The second ground on the back of the block is a backup. The engine itself is isolated from the frame by rubber engine mounts and may or may not have enough other contract for a reliable ground.
All the grounds need to be free of paint and corrosion. Both straps are important. A couple of years ago I also had a spate of bad voltage generators. Do pay attention to the directions installing the new one, to polarize it before running it, this is important.
Since you are trouble shooting electrical, you might also want to check the brushes in the generator and make sure the brushes are long enough and in good shape. This is primarily a cause of generator failure, worn brushes. Also, run some oil in the oil ports front and back for the bearings. It's a tiny little cap that looks like it belongs on the tin man from Wizard of oz.
Vintage you finally hit the culprit, I think. Super88, I have a 55. Let me walk you through the grounds. 1. In your first picture, the bolt on front of the block, is where the braided strap should attach. It is quite long, there is a hole in the middle of the strap that attaches to the battery tray. Then the strap continues up to the negative terminal of the battery. This part is available from Fusick. Depending on your current battery/post location, the braided strap may be a bit short. 2. Then there is another ground on the rt rear of the engine block that attaches to the firewall right by the block attach bolt. This is a secondary ground. As Vintage mentioned, the battery tray is not the best ground because there is usually so much corrosion around the battery tray. So, this may be enough ground to run the generator. Again, Vintage is correct, many charging problems are because of corrosion. The second ground on the back of the block is a backup. The engine itself is isolated from the frame by rubber engine mounts and may or may not have enough other contract for a reliable ground.
All the grounds need to be free of paint and corrosion. Both straps are important. A couple of years ago I also had a spate of bad voltage generators. Do pay attention to the directions installing the new one, to polarize it before running it, this is important.
Since you are trouble shooting electrical, you might also want to check the brushes in the generator and make sure the brushes are long enough and in good shape. This is primarily a cause of generator failure, worn brushes. Also, run some oil in the oil ports front and back for the bearings. It's a tiny little cap that looks like it belongs on the tin man from Wizard of oz.
Glad you got it working.
Dave
Dave - Good feedback. Wow, been a long time since I worked on a GEN & I'm surprised you remembered those two small oil port holes. That's good info.
Super88, I have a 55. Let me walk you through the grounds.
1. In your first picture, the bolt on front of the block, is where the braided strap should attach. It is quite long, there is a hole in the middle of the strap that attaches to the battery tray. Then the strap continues up to the negative terminal of the battery. This part is available from Fusick. Depending on your current battery/post location, the braided strap may be a bit short.
2. Then there is another ground on the rt rear of the engine block that attaches to the firewall right by the block attach bolt. This is a secondary ground. As Vintage mentioned, the battery tray is not the best ground because there is usually so much corrosion around the battery tray. So, this may be enough ground to run the generator. Again, Vintage is correct, many charging problems are because of corrosion. The second ground on the back of the block is a backup. The engine itself is isolated from the frame by rubber engine mounts and may or may not have enough other contract for a reliable ground.
All the grounds need to be free of paint and corrosion. Both straps are important. A couple of years ago I also had a spate of bad voltage generators. Do pay attention to the directions installing the new one, to polarize it before running it, this is important.
Since you are trouble shooting electrical, you might also want to check the brushes in the generator and make sure the brushes are long enough and in good shape. This is primarily a cause of generator failure, worn brushes. Also, run some oil in the oil ports front and back for the bearings. It's a tiny little cap that looks like it belongs on the tin man from Wizard of oz.
Glad you got it working.
Dave
oh yeah I have that braided ground with the hole in the middle but I didn’t use it. Anyways I was trying to adjust my timing tonight and next thing I knew the gen stopped working again!🤬. And it was sounding pretty bad making noises. So I’m not sure I’m stumped
Maybe, only thing I can think of is when I was putting the wires back on the gen I think I heard one of them crack because they are so old and brittle, but that would mean it worked for a day then stopped some how
Maybe, only thing I can think of is when I was putting the wires back on the gen I think I heard one of them crack because they are so old and brittle, but that would mean it worked for a day then stopped some how
If the wires are old & brittle they need to be replaced.
If a wire cracked (broke) there's nothing you can do to resolve that issue other than replace the wire. You can't just "think" & guess, you have to validate. Either it cracked (broke) or it didn't.
If the wires are old & brittle they need to be replaced.
If a wire cracked (broke) there's nothing you can do to resolve that issue other than replace the wire. You can't just "think" & guess, you have to validate. Either it cracked (broke) or it didn't.
I hear you and and agree. But if not did crack, could that let it run for a day then go out again?
Yes. Absolutely anything is possible. The GEN could still be shot. Test the wire(s) for continuity.
I just looked at those two wires and the outside of them did crack but the actual inside wire looks in tact, but I’ll probably end up replacing those all the way to the VR. Do you know what kind of grease goes in those generators? Mine was sounding obnoxious I don’t know if that had anything to do with it. Something’s up, not sure why it would work a day then I get the rpm’s up and it goes out again, maybe it wasn’t the VR to begin with
Post #55 . Oil holes in front and rear end plates to lube the generator. Oil, not grease. Pretty sure you have a bushing in the rear. If the bushing is gone, neither grease or oil will help. Front has a bearing and since it has been rebuilt before,I suspect there is a sealed bearing in it and even if it isn't sealed oil and grease won't help at this point.
Post #55 . Oil holes in front and rear end plates to lube the generator. Oil, not grease. Pretty sure you have a bushing in the rear. If the bushing is gone, neither grease or oil will help. Front has a bearing and since it has been rebuilt before,I suspect there is a sealed bearing in it and even if it isn't sealed oil and grease won't help at this point.
what is this bushing? What does it look like? I see the oil flippy caps. I don’t pay attention to the usernames on here too often, I believe someone said listen to the people on here who know this stuff which is why I’m asking questions, also because I want to learn how to fix my own stuff not send it to the shop when something goes wrong. No offense given to anyone. I do appreciate the advice. And yes I did get oils not grease
This is during my front end restoration. Take note of the ground strap on the rt side attached to the battery. The post is in the wrong spot so the strap was short. I now have a battery where the post is in the middle so I have the strap now bolted to the battery tray too.
Originally Posted by Super88chris
what is this bushing? What does it look like? I see the oil flippy caps. I don’t pay attention to the usernames on here too often, I believe someone said listen to the people on here who know this stuff which is why I’m asking questions, also because I want to learn how to fix my own stuff not send it to the shop when something goes wrong. No offense given to anyone. I do appreciate the advice. And yes I did get oils not grease
Super88.
The crack you heard was the insulation cracking. The wire inside should be fine, but obviously will need to be replaced at some point, but should be good for trouble shooting for now at least.
40 to 50 wt oil should be fine for the lube fittings on the generator, the little flip caps. I'll say it again, CHECK the brushes. They will fail and make rattling noises if they are worn and too short. It might work intermittently. You can replace just the brushes at significant savings. The armature of the generator turns inside the generator case. It has a bushing or bearing at the front and rear--hence the oil cap-fittings.
Did you polarize the voltage regulator? This will also work intermittently if you didn't.
Do you have the secondary ground from the engine block at the back to the firewall?
This is a good place to learn. You are asking good questions. Google and Utube are a great help too.
I've included a picture that might help. This is my generator that failed due to worn brushes. The brushes are at the back of the generator and fit into little holders on either side of the back of the shaft.
This is during my front end restoration. Take note of the ground strap on the rt side attached to the battery. The post is in the wrong spot so the strap was short. I now have a battery where the post is in the middle so I have the strap now bolted to the battery tray too.
Super88.
The crack you heard was the insulation cracking. The wire inside should be fine, but obviously will need to be replaced at some point, but should be good for trouble shooting for now at least.
40 to 50 wt oil should be fine for the lube fittings on the generator, the little flip caps. I'll say it again, CHECK the brushes. They will fail and make rattling noises if they are worn and too short. It might work intermittently. You can replace just the brushes at significant savings. The armature of the generator turns inside the generator case. It has a bushing or bearing at the front and rear--hence the oil cap-fittings.
Did you polarize the voltage regulator? This will also work intermittently if you didn't.
Do you have the secondary ground from the engine block at the back to the firewall?
This is a good place to learn. You are asking good questions. Google and Utube are a great help too.
I've included a picture that might help. This is my generator that failed due to worn brushes. The brushes are at the back of the generator and fit into little holders on either side of the back of the shaft.
Dave
ok awesome that’s a lot of good info! My brushes are good and not worn down and I did you use that type oil. How do I polarize?? Can you explain in detail please? That would explain why it worked yesterday for a few hours then stopped and did the same today
ok awesome that’s a lot of good info! My brushes are good and not worn down and I did you use that type oil. How do I polarize?? Can you explain in detail please? That would explain why it worked yesterday for a few hours then stopped and did the same today
and yes I do have the ground from the block to firewall
You are actually polarizing the GEN, not the VR. You're using the VR as the location to polarize the GEN (because the VR is the grounding point in an "A" circuit). As indicated in the URL link provided (above, Polarizing The Electrical System), there are essentially two types of circuits: (1) "A" circuit & (2) "B" circuit. I believe you have an "A" circuit (used on most GM cars). "A" circuit the FIELD is grounded via the VR; and, "B" circuit the FIELD is grounded internally through the GEN.
Do this w/ the battery disconnected. Therefore, disconnect the battery BEFORE you begin. Since you already have the three wires (BAT, ARM & FLD) attached to the VR, you're fine - just leave them attached. Next, re-connect the battery. Using a simple jumper wire perform the following:
To polarize an "A Circuit" system, connect the FIELD, ARMATURE, and BATTERY leads to the regulator. Connect the battery. Then, momentarily connect a jumper wire between the ARMATURE terminal and the BATTERY terminal at the regulator.
Here is a very simple video (below) of polarizing a GEN via the VR. Note the terminals will be different since the video isn't the same as your VR.
Your VR should look like the one I've posted (below).
Oh ok that’s seems simple enough! Thank you. I saw another video about polarizing on YouTube but it was on a tractor. And they said you have to do this polarizing step every time you disconnect the battery. Is this true. Thanks for the info I’m pretty certain this is why my generator works off and on.
Oh ok that’s seems simple enough! Thank you. I saw another video about polarizing on YouTube but it was on a tractor. And they said you have to do this polarizing step every time you disconnect the battery. Is this true. Thanks for the info I’m pretty certain this is why my generator works off and on.
Actually, most of my experience w/ generators comes from having worked w/ large agriculture tractors manufactured in the 1940s & 1950s. I recall no occasion when the disconnection of the battery and re-connection of the battery required polarization of the GEN during normal operating conditions. Yeah, maybe a piece of machinery which never had a battery installed in it, or a piece of machinery which hasn't had the battery in it for a couple years may be the exception. The only time polarization was performed was if the VR &/or the GEN was removed or the wires to/from each unit were removed/replaced. The GEN does one thing - it supplies voltage to the battery. It does nothing else. As the battery discharges voltage, the battery's voltage is used to perform work (run headlights, start the engine, run the radio, defroster, yadda, yadda) & the voltage discharged from the battery must be replaced, the GEN recharges the BAT voltage. The voltage supplied to the BAT from the GEN needs to flow in one direction only - i.e. DC = Direct Current. The flow is in one direction (as opposed to AC where flow is in both directions, the flow is occasionally reversed). Anyhow, with that said. the GEN has no idea which way to send voltage to the battery until it is polarized. So, you polarize the GEN and tell it which direction to send voltage into the battery.
We're beginning to borderline the difference between a conventional electric circuit (diagram) and an electron (flow) circuit (diagram) - which I am attempting not to become weighted down with & add any confusion.
Actually, most of my experience w/ generators comes from having worked w/ large agriculture tractors manufactured in the 1940s & 1950s. I recall no occasion when the disconnection of the battery and re-connection of the battery required polarization of the GEN during normal operating conditions. Yeah, maybe a piece of machinery which never had a battery installed in it, or a piece of machinery which hasn't had the battery in it for a couple years may be the exception. The only time polarization was performed was if the VR &/or the GEN was removed or the wires to/from each unit were removed/replaced. The GEN does one thing - it supplies voltage to the battery. It does nothing else. As the battery discharges voltage, the battery's voltage is used to perform work (run headlights, start the engine, run the radio, defroster, yadda, yadda) & the voltage discharged from the battery must be replaced, the GEN recharges the BAT voltage. The voltage supplied to the BAT from the GEN needs to flow in one direction only - i.e. DC = Direct Current. The flow is in one direction (as opposed to AC where flow is in both directions, the flow is occasionally reversed). Anyhow, with that said. the GEN has no idea which way to send voltage to the battery until it is polarized. So, you polarize the GEN and tell it which direction to send voltage into the battery.
We're beginning to borderline the difference between a conventional electric circuit (diagram) and an electron (flow) circuit (diagram) - which I am attempting not to become weighted down with & add any confusion.
thank you that makes sense to me more now. And I agree, I’ll polarize it today when I get home! All that info is way better than trying to find it on google so I appreciate it. And thanks for clearing it up about polarizing every time after disconnecting the bat. I had just saw that on YouTube and wanted to double check.
thank you that makes sense to me more now. And I agree, I’ll polarize it today when I get home! All that info is way better than trying to find it on google so I appreciate it. And thanks for clearing it up about polarizing every time after disconnecting the bat. I had just saw that on YouTube and wanted to double check.
I polarized the gen from the VR, and it did exactly what it was supposed to and works great now! That thing about made me give up on it, but thanks to all you guys help it worked out.
I polarized the gen from the VR, and it did exactly what it was supposed to and works great now! That thing about made me give up on it, but thanks to all you guys help it worked out.
Excellent!
Vintage, yes, you got it.
Super88, normally, you only need to polarize it once with a new Gen or VR. If for some reason you change parts or have the battery out for a very long time, meaning years, you might have to do it again, but not usually.
Super88, normally, you only need to polarize it once with a new Gen or VR. If for some reason you change parts or have the battery out for a very long time, meaning years, you might have to do it again, but not usually.
Chris, if you decide to go with the alternator, here is how you should wire it. No need to go through the voltage regulator because the GM alternator has an internal regulator. This is how I have the alternator on my '56 wired and it works perfectly!
