Major Wiring Experts Needed!
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
You are running the charging current through a 20A fuse. Get rid of the fuse and use a fusible link on that wire.
You should be running a 6 gauge wire from the alternator to the solenoid or your terminal block if you are using the higher current alternator that came with the engine. You'll need it anyways to power everything properly.
They look nice but the fans in this case are Spal.
You should be running a 6 gauge wire from the alternator to the solenoid or your terminal block if you are using the higher current alternator that came with the engine. You'll need it anyways to power everything properly.
They look nice but the fans in this case are Spal.
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
You are running the charging current through a 20A fuse. Get rid of the fuse and use a fusible link on that wire.
You should be running a 6 gauge wire from the alternator to the solenoid or your terminal block if you are using the higher current alternator that came with the engine. You'll need it anyways to power everything properly.
They look nice but the fans in this case are Spal.
You should be running a 6 gauge wire from the alternator to the solenoid or your terminal block if you are using the higher current alternator that came with the engine. You'll need it anyways to power everything properly.
They look nice but the fans in this case are Spal.
I had this car up and running 2 years ago with the current wiring so I guess it's the fact I added the fuse vs. going straight off the starter post.
What is the amp difference between the old 69 alternator vs. the LS1? It does make sense I want to add bigger wire BUT...what about the wire going to the stock fuse block? will it still only draw what it's using I assume?
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
Okay. My understanding of alternators was incorrect according to my 10min of google research lol.
For some reason I thought the output of the alternator got grounded and fed back through to the battery on the negative end...completing a cycle. Blonde moment I had I guess...even though I have brown hair.
I'll get a bigger cable (with fusible links...) run from the alternator to solenoid before I run it again and eliminate the fuse and old wiring.
Probably just lucky in the past I didn't burn anything down with the 12g wire from the stock '69 alternator/starter stuff.
For some reason I thought the output of the alternator got grounded and fed back through to the battery on the negative end...completing a cycle. Blonde moment I had I guess...even though I have brown hair.
I'll get a bigger cable (with fusible links...) run from the alternator to solenoid before I run it again and eliminate the fuse and old wiring.
Probably just lucky in the past I didn't burn anything down with the 12g wire from the stock '69 alternator/starter stuff.
Le Mans Master
Joined: May 2003
Posts: 8,877
Likes: 3,556
From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
I got rid of the GM horn relay and buzzer all together. Just added a Bosch relay to control the horns and ran the alt output directly to the battery but the starter lug is fine.
I would look at something like this (pic) to protect the electricals- usually if the Alt is shorted - it'll burn up- where as the battery is a different story. Fuses come in several different sizes- up to 300A.
I would look at something like this (pic) to protect the electricals- usually if the Alt is shorted - it'll burn up- where as the battery is a different story. Fuses come in several different sizes- up to 300A.
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
I got rid of the GM horn relay and buzzer all together. Just added a Bosch relay to control the horns and ran the alt output directly to the battery but the starter lug is fine.
I would look at something like this (pic) to protect the electricals- usually if the Alt is shorted - it'll burn up- where as the battery is a different story. Fuses come in several different sizes- up to 300A.
I would look at something like this (pic) to protect the electricals- usually if the Alt is shorted - it'll burn up- where as the battery is a different story. Fuses come in several different sizes- up to 300A.
Still not sure how i'm going to get it home safe on a Uhaul trailer without a windshield and windows in.... hope it doesn't rain I guess!
Le Mans Master
Joined: May 2003
Posts: 8,877
Likes: 3,556
From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
Good luck w/ the move AND the career change...I've done both and they are not on my list of fun things to do!!!
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
Okay.... so the 140amp? alternator is back feeding power to the new fuse block and blowing my newly added fuse?
I had this car up and running 2 years ago with the current wiring so I guess it's the fact I added the fuse vs. going straight off the starter post.
What is the amp difference between the old 69 alternator vs. the LS1? It does make sense I want to add bigger wire BUT...what about the wire going to the stock fuse block? will it still only draw what it's using I assume?
I had this car up and running 2 years ago with the current wiring so I guess it's the fact I added the fuse vs. going straight off the starter post.
What is the amp difference between the old 69 alternator vs. the LS1? It does make sense I want to add bigger wire BUT...what about the wire going to the stock fuse block? will it still only draw what it's using I assume?
Where does the main power lead for you new terminal block come from? Where is it mounted?
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
I mounted in the passenger glove box area. 0/1 gauge wire going off the battery.
I kept the stock wire that goes to the starter still but no longer steal power from that post anymore for anything.
After seeing how bad fusible links fail I don't think I want to use them so might look at other options or just run a wire from alternator to starter and call it good.
I think i'll also replace the old horn relay with one in the current fuse block when i rewire things. clean up that engine bay wiring a bit more.
Last edited by PUNISHER VETTE; Mar 16, 2015 at 12:16 PM.
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Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
You could run the alternator wire to the terminal block and pull the feed wire for the original fuse block from the bulkhead connector and run it to the terminal block too. Then, you can remove all the old 10 gauge wiring and the horn relay from under the hood.
I would also suggest you run the voltage sensing wire from the alternator plug back to your terminal block so the alternator maintains the full 14.2V at the terminal block.
I would also suggest you run the voltage sensing wire from the alternator plug back to your terminal block so the alternator maintains the full 14.2V at the terminal block.
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
You could run the alternator wire to the terminal block and pull the feed wire for the original fuse block from the bulkhead connector and run it to the terminal block too. Then, you can remove all the old 10 gauge wiring and the horn relay from under the hood.
I would also suggest you run the voltage sensing wire from the alternator plug back to your terminal block so the alternator maintains the full 14.2V at the terminal block.
I would also suggest you run the voltage sensing wire from the alternator plug back to your terminal block so the alternator maintains the full 14.2V at the terminal block.
There is a single wire coming out of the alternator that PSI supplied going back to the PCM. Not sure what it does or if this is the sensing wire you're talking about?
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
Grrrrrrrr
So I went to start it today to see if my clutch bleeding was successful or not(it was leaking when I tried to manually bleed it and wasn't getting a good pedal to get it into gear so I used my mighty vac...hoping it worked.)
Anyway. The starter won't engage now. Just one click then nothing.
Tried jumping the post and still nothing. Just more sparks and clicks. But wasn't sure if this works with a manual since there's the clutch pedal switch? or does jumping it bypass that?
Should I assume it's a bad solenoid? Should I take it all out and test it? How do I know the motor isn't seized up for a worst case scenario?
Battery is charged and should be good. although I still have the old battery I guess. All the fuses are still good and getting proper volts, fuel pump sounds good.... just a single Click.
Anyway. The starter won't engage now. Just one click then nothing.
Tried jumping the post and still nothing. Just more sparks and clicks. But wasn't sure if this works with a manual since there's the clutch pedal switch? or does jumping it bypass that?
Should I assume it's a bad solenoid? Should I take it all out and test it? How do I know the motor isn't seized up for a worst case scenario?
Battery is charged and should be good. although I still have the old battery I guess. All the fuses are still good and getting proper volts, fuel pump sounds good.... just a single Click.
Last edited by PUNISHER VETTE; Mar 17, 2015 at 07:37 PM.
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
Well I took the starter off.
Using my jumper pack(didn't have jumper cables to a real battery)
With a screw driver I can get the solenoid to engage. crates a loud noise and sparks and jumps and scares me every time lol...so it's hard to get a consistent test.
BUT... I don't notice the motor actually spinning much. When i did see it move it was super slow.
So I either have:
1. a poor connection/bridge with the screw driver.
2. the jumper pack isn't strong enough? I think no as it's sole purpose is to get a vehicle started again.
or 3. The starter is actually bad and doesn't want to spin very well.
EDIT: Nevermind...just saw online you can't use a jumper pack.. not sure why but it just said it wouldn't work
Using my jumper pack(didn't have jumper cables to a real battery)
With a screw driver I can get the solenoid to engage. crates a loud noise and sparks and jumps and scares me every time lol...so it's hard to get a consistent test.
BUT... I don't notice the motor actually spinning much. When i did see it move it was super slow.
So I either have:
1. a poor connection/bridge with the screw driver.
2. the jumper pack isn't strong enough? I think no as it's sole purpose is to get a vehicle started again.
or 3. The starter is actually bad and doesn't want to spin very well.
EDIT: Nevermind...just saw online you can't use a jumper pack.. not sure why but it just said it wouldn't work
Last edited by PUNISHER VETTE; Mar 17, 2015 at 09:51 PM.
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
It sounds like your starter failed.
Jumper to the starter motor power terminal directly to see the motor work without the solenoid being in the circuit.
I would ignore that comment because if a booster pack can start an engine when the battery is dead then it is capable of running an unloaded starter motor.
Jumper to the starter motor power terminal directly to see the motor work without the solenoid being in the circuit.
I would ignore that comment because if a booster pack can start an engine when the battery is dead then it is capable of running an unloaded starter motor.
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
I went to try and clean the terminals on it today because for a split second the starter turned on so i figured they were pretty corroded.
nut/stud to the starter was seized up and ended up shattering the plastic part on the solenoid. So I called up a local starter repair Mennonite I saw on google and he said he'd replace a lot of it for $70 or so within a day. Figured that was a decent deal.
You go to autozone they'll hose you for $150 for a cheapo remanded one.
nut/stud to the starter was seized up and ended up shattering the plastic part on the solenoid. So I called up a local starter repair Mennonite I saw on google and he said he'd replace a lot of it for $70 or so within a day. Figured that was a decent deal.
You go to autozone they'll hose you for $150 for a cheapo remanded one.
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
$80, had it done in 5hrs on the same day I called in some random farm shed full of tractor alternators. amazing lol.
slapped it back on and it fired right up! And my clutch bleeding with my mightyvac worked too so it's able to move now!
slapped it back on and it fired right up! And my clutch bleeding with my mightyvac worked too so it's able to move now!