cs130 alternator conversion on 68 vette
Thread Starter
Instructor
Joined: Apr 2016
Posts: 166
Likes: 6
cs130 alternator conversion on 68 vette
im having troubles converting to a cs130 alternator in my 68. engine bay wiring harness is brand new so i know thats all good. never had any other alternator in it because i rebuilt the car. i bought two adapters
1. to convert oem plug to si alternator plug style (https://www.summitracing.com/parts/aww-27555)
2. to convert si to cs alternator plug style (https://www.summitracing.com/parts/pco-5327pt)
i have my alternator on the passenger side of the car and after i hooked it all up its not charging so i got the alternator tested and the alternator itself works. any ideas on what to do??? Ill post pics in the morning
1. to convert oem plug to si alternator plug style (https://www.summitracing.com/parts/aww-27555)
2. to convert si to cs alternator plug style (https://www.summitracing.com/parts/pco-5327pt)
i have my alternator on the passenger side of the car and after i hooked it all up its not charging so i got the alternator tested and the alternator itself works. any ideas on what to do??? Ill post pics in the morning
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
The big red wire should measure battery voltage.
The brown wire should be switched battery voltage. However, it should have a resistor or light in series and I believe your 68 used direct power on that wire. So, you need an adapter with a resistor.
Still, check the brown wire. The alternator won't start working if that terminal doesn't get power applied to it.
The alternator should only need the light connected. So, as a test you could try unplugging the connector. With the engine off take a test light and hook the main lead to the big battery post on the alternator and then probe the L terminal. The light should light. Now, start the engine and do it again. The alternator should start charging and the battery voltage should rise up to 14V or so.
The brown wire should be switched battery voltage. However, it should have a resistor or light in series and I believe your 68 used direct power on that wire. So, you need an adapter with a resistor.
Still, check the brown wire. The alternator won't start working if that terminal doesn't get power applied to it.
The alternator should only need the light connected. So, as a test you could try unplugging the connector. With the engine off take a test light and hook the main lead to the big battery post on the alternator and then probe the L terminal. The light should light. Now, start the engine and do it again. The alternator should start charging and the battery voltage should rise up to 14V or so.
Thread Starter
Instructor
Joined: Apr 2016
Posts: 166
Likes: 6
The big red wire should measure battery voltage.
The brown wire should be switched battery voltage. However, it should have a resistor or light in series and I believe your 68 used direct power on that wire. So, you need an adapter with a resistor.
Still, check the brown wire. The alternator won't start working if that terminal doesn't get power applied to it.
The alternator should only need the light connected. So, as a test you could try unplugging the connector. With the engine off take a test light and hook the main lead to the big battery post on the alternator and then probe the L terminal. The light should light. Now, start the engine and do it again. The alternator should start charging and the battery voltage should rise up to 14V or so.
The brown wire should be switched battery voltage. However, it should have a resistor or light in series and I believe your 68 used direct power on that wire. So, you need an adapter with a resistor.
Still, check the brown wire. The alternator won't start working if that terminal doesn't get power applied to it.
The alternator should only need the light connected. So, as a test you could try unplugging the connector. With the engine off take a test light and hook the main lead to the big battery post on the alternator and then probe the L terminal. The light should light. Now, start the engine and do it again. The alternator should start charging and the battery voltage should rise up to 14V or so.
Thread Starter
Instructor
Joined: Apr 2016
Posts: 166
Likes: 6
The big red wire should measure battery voltage.
The brown wire should be switched battery voltage. However, it should have a resistor or light in series and I believe your 68 used direct power on that wire. So, you need an adapter with a resistor.
Still, check the brown wire. The alternator won't start working if that terminal doesn't get power applied to it.
The alternator should only need the light connected. So, as a test you could try unplugging the connector. With the engine off take a test light and hook the main lead to the big battery post on the alternator and then probe the L terminal. The light should light. Now, start the engine and do it again. The alternator should start charging and the battery voltage should rise up to 14V or so.
The brown wire should be switched battery voltage. However, it should have a resistor or light in series and I believe your 68 used direct power on that wire. So, you need an adapter with a resistor.
Still, check the brown wire. The alternator won't start working if that terminal doesn't get power applied to it.
The alternator should only need the light connected. So, as a test you could try unplugging the connector. With the engine off take a test light and hook the main lead to the big battery post on the alternator and then probe the L terminal. The light should light. Now, start the engine and do it again. The alternator should start charging and the battery voltage should rise up to 14V or so.
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Le Mans Master
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Here is the guidance to find adapter for a CS-144..... should work for a CS-130 from what I have researched. If nothing else you'll know how to measure resistance.
I also had converted my 68 from 10si to 12si. I bought the 12si-to-CS adapter because when I did it CS-144s were still somewhat rare. Works out good though, I swapped in my old 12si one day when I thought I had messed up my CS-144 and it worked just fine.
You can do the quick check below to see what adapter you need to convert from 12si to CS-144 ...then go to the local parts store and get the equivalent part.
I went to NAPA, mine took Echlin part # ECH EC82 .... according to NAPA website that is part interchange number for 8078 in text below.
(Per NAPA website:
8077 cross-references to Echlin part #ECH EC80
8078 cross-references to Echlin part #ECH EC82)
(****THAT WAS FOR MY VEHICLE ---YOU NEED TO DETERMINE YOURS****KEEP READING).
"If you are unsure which adapter to use, measure the resistance of the exciter line. Disconnect the positive battery cable and the alternator plug. Connect an ohm meter between the #1 terminal on the plug end of the alternator harness and the end of the positive battery cable. Turn the ignition key to the "on" position and read the ohmmeter. If resistance is less than 35 ohms, use adapter #8078. If it’s between 35-350 ohms, use #8077. If it’s more than 350 ohms, you have excessive resistance somewhere in that circuit which needs to be repaired, first."
...the above text is from idavette dot net (doesn't appear to work anymore).
that's the guidelines I used to wire mine in and it worked from the get-go.
I also had converted my 68 from 10si to 12si. I bought the 12si-to-CS adapter because when I did it CS-144s were still somewhat rare. Works out good though, I swapped in my old 12si one day when I thought I had messed up my CS-144 and it worked just fine.
You can do the quick check below to see what adapter you need to convert from 12si to CS-144 ...then go to the local parts store and get the equivalent part.
I went to NAPA, mine took Echlin part # ECH EC82 .... according to NAPA website that is part interchange number for 8078 in text below.
(Per NAPA website:
8077 cross-references to Echlin part #ECH EC80
8078 cross-references to Echlin part #ECH EC82)
(****THAT WAS FOR MY VEHICLE ---YOU NEED TO DETERMINE YOURS****KEEP READING).
"If you are unsure which adapter to use, measure the resistance of the exciter line. Disconnect the positive battery cable and the alternator plug. Connect an ohm meter between the #1 terminal on the plug end of the alternator harness and the end of the positive battery cable. Turn the ignition key to the "on" position and read the ohmmeter. If resistance is less than 35 ohms, use adapter #8078. If it’s between 35-350 ohms, use #8077. If it’s more than 350 ohms, you have excessive resistance somewhere in that circuit which needs to be repaired, first."
...the above text is from idavette dot net (doesn't appear to work anymore).
that's the guidelines I used to wire mine in and it worked from the get-go.
Last edited by carriljc; Sep 1, 2017 at 08:04 PM. Reason: add part interchange comment
Le Mans Master
Joined: Jan 2001
Posts: 6,743
Likes: 1,385
You need to measure your circuits as pointed out above.
According to the Summit website, that adapter you mentioned above,
does NOT have any resistance built into it. See the comments section where that is stated:
(2. to convert si to cs alternator plug style (https://www.summitracing.com/parts/pco-5327pt)
Go measure the resistance and then post that value and we can help you.
We can then look up specific CS-130 adapters but I just went and looked at mine and the ends look the same. My 68 adapter has resistance in the adapter. I just checked it. ACTUALLY --- once I disconnected to measure, and reconnected, then the dang alternator would NOT charge.... I had to adjust (tweak) the terminal connectors at the ends to make good contact again. So.... you might want to check that, but I think you have the incorrect adapter since you also have a 1968.
According to the Summit website, that adapter you mentioned above,
does NOT have any resistance built into it. See the comments section where that is stated:
(2. to convert si to cs alternator plug style (https://www.summitracing.com/parts/pco-5327pt)
Go measure the resistance and then post that value and we can help you.
We can then look up specific CS-130 adapters but I just went and looked at mine and the ends look the same. My 68 adapter has resistance in the adapter. I just checked it. ACTUALLY --- once I disconnected to measure, and reconnected, then the dang alternator would NOT charge.... I had to adjust (tweak) the terminal connectors at the ends to make good contact again. So.... you might want to check that, but I think you have the incorrect adapter since you also have a 1968.
Last edited by carriljc; Sep 5, 2017 at 01:46 PM. Reason: updated