im going crazy with the electrical

[jeff5347]

I was reading this post and have read the Madelectrics site but am stumped as i am not an electrical expert or even novice https://www.pro-touring.com/forum/sh...ght=alternator
I was reading this post on how to wire the alternator to a block and then have the assc branch off that. Could someone do a diagram of how these wires should should be laid out. I am running a black magic fan that pulls 30 amps, a cassette radio (nothing fancy), msd ignition and the usual stuff, headlights, and such. I am sure i have a 63 amp alt but think it is a little small. In the day with the fan running the volt gauge reads 13.5 but put the headlights on and it drops to just about 12 if not lower and seems the battery doesnt hold a charge worth a dime as i always need to hook up the charger to start it. If i put the blinkers on at any time the gauge "blinks" also. im at loss. Oh by the way once i start the car and drive for say 10-15 miles then shut it off and try to start it later like 2-3 or so hours later it starts without a problem. Can anyone help on my problems?
Im desparate

[David Pozzi]

Your other thread should have been posted as a reply to this message so all the info is in one place. You'll get better response that way.

On a camaro the junction block is the horn relay, you should have 13.5 to 14.5 volts there, the alt terminal may be higher, it doesn't matter. All add-ons should take their power from the horn relay terminal.
A cheap digital volt meter is a good tool to have.

Do you have the stock type alternator with remote voltage regulator on the radiator support?
Is it the old mechanical regulator?

Check all battery terminals and connections to the block for ground, you need good clean metal to metal grounds.

[jeff5347]

Hi David,
Sorry about the additional post. The alt is a GM internally regulated alt. I do still have the horn relay behind the front driver headlight. The battery terms are clean but i will do thewm again to make dbl sure. One thing is the battery is in the trunk. I have it grounded to the bumper bolt inside. What other places should a ground be and would that make a difference. Most all of the aftermarket wiring i have for the fans, radio, alt and such is in good cond and in good bare mettal spots. Any other info i can use to work on. Also do you think that if the alt reads fine with no assc on then drops to very low with all assc on then i need a higher amp alt?

[Charley Lillard]

Spend some money on a alt that puts out at least 100 amps. I think I have a Tuff Stuff 140 amp in the Mule.

[black67ls1]

I know Mad Electrical's website says ground the trunk mounted battery in the trunk, but I was hesitant to do that since the body of the car is not as good a conductor as a huge copper wire. I ran ground cable from the batter to the front of the engine block and I have braided steel ground straps from the block to the subframe and to the firewall. I suspect that's part of the problems you're having. Mine works great.

[jeff5347]

I am going to get at least a 100 amp like you stated Charley, thanks. I thinks its been a long time coming. So the ground to the body may not be enough? I will do the engine to sub and to the firewall. Do you think putting a relay 12v/30amp on the fan will help? Also 2 other things. Would the low amp alt i have be contributing to the not enough power to start the car. Meaning it cant keep up with all the electric and charge the batt at the same time. Would a higher amp alt help the charging issue? Also im gonna go junkyarding on sat and wondering what donor car i can get a cs130 i think it is, off of or at least a 100-140 amp alt to do the conversion? Thnaks again for all the help guys.

[David Pozzi]

The MAD site is the best advice you can find.
You probably need a higher amp alternator, the fan takes a lot of amps.
There is alt conversion info on the team camaro site:
http://www.camaros.net
Here is the alt conversion page: http://www.camaros.net/techref/ftecref14.html

I'm not convinced you need to run a ground cable all the way up to the engine from the trunk. Seel is not as good a conductor as copper but there is a lot less copper in a cable compared to 3000 pounds of steel in the unibody.

I'd rather use a larger batery positive cable and body ground (bumper bolt) than two regular cables running to the engine. battery in trunk installations can have more loss than stock location, so your battery cold cranking amps, state of charge, battery cable size, and starter power all need to be optimum. The chain is only as good as it's weakest link.

Try running jumper cables from the bat ground to the engine block and see if there is an improvement in cranking, but first get your charging problem solved.

[jeff5347]

thanks Dave, just to let you know ive read your site and got some great info off of it so keep educating us. I will look to see how the ground is and what i can do to beef it and the pos up. Do you or anyone think a relay for the fan rather than running right off a junction block will help.?

[David Pozzi]

According to MAD, the 12SI alternator is a 94 amp unit. I'm not sure if it's the same size as the more common 10SI which is probably what you have now.
Look at an 84 Camaro with air/305 alternator and see if it's the same size as yours.
http://www.madelectrical.com/catalog/alt-1.shtml
http://www.madelectrical.com/electri...elcoremy.shtml

[OHCbird]

Jeff-
As for the dimming when you put your lights on, did you check all your connections? You'll lose 1vdc when you switch them on, but you shouldn't get the cycling (the MSD can suck some juice, however). As for the starting problem, get a remote relay to deliver full 12Vdc to the starter solenoid (MAD also sells these). You're getting heat soak in your starter- when it heats up, it 'needs' more volts to get the same amount of power to crank your engine. You should have realays supplying power to your fans, your starter, and your lights.

You have an internally regulated alt, correct? Did you get rid of the stock regulator on the radiator support?

concerning grounds, where are your ground cables up front?

My suggestions for you:
1. Get at least a 12SI or CS-130D (not a regular CS-130). The adapter harnesses / connectors take 10 minutes. Shoot for at least 100 amps (105amp is a very common CS-130D). The CS series make alot more amps at lower RPMs than most 12SIs, so it will help you run your fans without discharging your battery at slow speeds.
2. Check ALL of your lighting connections- you've got a crappy connection somewhere. Don't forget to OHM-out your grounds to make sure you are as close to zero ohms as possible.
3. Run an extra ground from the body to the chassis, and then to the negative post using 2/4ga. wire. I suspect you might only have the factory braided-wire connection hooked from the body to the chassis, and these often corrode.

[David Pozzi]

Just to backtrack a bit. make sure you are reading voltage with a good digital voltmeter that you can trust. It doesn't have to be very expensive.

With engine NOT running, use this chart to determine battery state of charge.
STATE
OF
CHARGE ----VOLTS
100%---------12.66
75%----------12.45
50%----------12.24
25%----------12.06
0%-----------11.89

According to MAD, you need a running voltage of 14.2v to 14.5v at the horn relay junction. Your alternator "sense" wire should be connected to this junction. If the "Sense" wire is connected to the alt "Bat" lug, the alternator is functioning as a "one wire" alternator and that isn't as good a method.

[jeff5347]

Bird,
i do have the battery in the trunk and also have a ford style solenoid in the trunk to not have the heat soak. The grounds i checked are from the bat to the inside bumper bolt, engine to body via the flat copper braid. Ill have to ground to the frame and body asd i wasnt able to find that ground. I have relays for the fan and lights but not the starter . i will get a 12v 30a for the starter. Is that enough?
As for the wiring the lights have the original wiring except for the relays wired in, they are 10 gg. The fasn is wired with the 10gg also. As for the alt i have
1.the batt lug wired back to the battery
2. have to look tonight but the wire out of the connector to the batt lugg and also out to junction behind where the batt used to sit.
3. The other wire out of the conn goes to the blue wire 9either the one that is was used for the volt reg or the is another blue wire from the harness. How exactly should the alt be wired. It is an int reg alt.
Maybe i need a def answer on how it wires up correctly.

[jeff5347]

heres a bad diagram on how it is wired

[David Pozzi]

The lower wire coming out of the white plug is the voltage sense wire, this wire should be connected to the horn relay junction.

You don't need another starter relay if you allready have one in the trunk.

[jeff5347]

David,
I do have the lowest wire on the connector to the batt lug on the back of the alt like your pic. Then that wire i have to a bluee wire in the harness on the drivers side. I will do that tonight reconnect that to the batt on the horn relay. Will or should i see some difference in voltage at the headlights. I have the + for the relays on the headlights connected to the batt junc that is behind the battery. Also i know you might not know without a pic but what could the blue wire be that i have the pos of the alt going to? I hate electrical because there are so may ways to screw things up. Again David thanks for the help. Always appreciated.
Jeff

[BRIAN]

Try Ron Francis for info. Actually American Autowire has good catalog also. The problem is you are working with a nest of wires that are 30yrs old. Then there is the alternator. When buying and alt always check the output at idle. Yes, that is the idle YOUR car idles at. You will be surprised how that 100 amp alt puts out a 1/3 of that at idle. Now add all your accys and you can see the problem. Try Performance Distributors they have real high output alt. You will be surprised at idle with the accys on that your shiny 150 amp fancy alt is putting out 12.0 amps of charge at the battery.

You also have to update the wiring size from the alternator. Go with the biggest you can get on there. The wire size can choke your output. You can run a junction block for your accys from there. Try a boat supply place like Boaters World. They have all the cable and connections you will need.

Also the grounds are a big deal. You have to ground the block, body, power, and just about every accy. You can also do this with a distribution block. Most new cars do have ground distribution blocks as noted on Mad's site.

Good luck.

[David Pozzi]

I think in the end you need a higher amp alternator. I just wanted to make sure your alternator is sensing voltage from the horn relay.

Brian makes a good point, even a high amp alternator isn't going to put out full rated amps at idle.

If you had an ammeter in the alternator output circuit, you could measure what it's putting out. Measuring volts is almost as good, if you it doesn't develop enough volts, it isn't developing enough amps either.

Your electric fan is taking the most juice, the ignition can use 8 to 10 amps. Make sure the subframe is well grounded to the unibody, that's all I see that you still need to do.

[jeff5347]

Ok let me ask this then. My father being a mechanic has a volt, dwell, ampmeter. If i grab it for a day or so how do i measure amp on the alt. Where do i connect the + and -. I will get to the bottom of this and get this fixed. what vehicle should i get a good high amp alt off of. Im thinking a 140 amp alt. Any donors that i can get it off of or go to autozone and let them know what vehicle i "have".

[jeff5347]

ok an update for yuo all. i cleaned the contacts on the batter and the terminals. Took apart all grounds fro front markers, headlights, fan and anything grounded up fron and cleaned them and made some better grounds and also had purchased a 108 amp alt. Wheni put the alt on it seemed to help a bit. once i cleaned the contacts viola!!!! Now it shows on the VM with nothing on except the car running at 14.3 volts!!! Nice i say. Turn just the headlights on and i think from cleaning the grounds a slight (maybe .3-.5 drop) nothing like the 1-1.5 drop likebefore. Turn the fan on with the headlights on and im at 13.5 volts. Before i was at 12 if not a bit less. When i put the blinkers on the gauge still moves with the blinker but not as much as before. So i think to make a better difference is that i will put the ground straps on. I didnt think that this would help but it def does help to make sure the grounds are as clean as can be.

I was thinking like this for grounding more, what do you think?
Engine is grounded to firewall. (will disconnect and clean and reinstall)
Rad support to frame
frame to firewall
front clip such as inner fenderwell to frame.
Batt - is connected to the right side bumper bolt. May not be the best so i will also run a ground from batt- to inside the car to say a seatbelt bolt. Any other ideas? Am i overkilling with the grounds? Would you add or delete some of what im thinking of doing?
Also im gonna do this tomorrow so i ll keep ya posted.

Thanks a bunch for everyones help.

[gmachinz]

It's been my experience that you should only use around 70% of your alternator max. output or capability as far as amperage is concerned. So, if you have an amp probe, (most multi-meters don't have a setting higher than 10-amp fused for checking DC amps, so you may have to search a bit...) turn on all of your accessories and anything else that draws power including everything in your fuse box-i.e. tail lights, blower motor, wiper motor, etc. and add up your total system draw. Then, make sure that is no more than 70% of your alternators total output rating. If it is more, you should step up to a little higher amperage alternator. You need to help keep your alternator cool so it can easily handle any electrical load placed on it. 30 amps is a ton of amperage draw for a set of fans. If you insist on using that style of cooling fan, you should go with a 50-70 amp relay. I'm not a big fan of relay triggered fans anymore but for that one, I wouldn't go with a cheapo 30-amp one. Those fan motors at full speed will run hot and if you go with a cheaper style relay, it could get hot if you push it to it's max and if it shorts and keeps the fan running, you'll have a problem. You do not want those fans staying on for long periods of time so I would suggest using a temperature switch in the range of 205on/190off and going with an aluminum radiator and a 180-degree thermostat. That way, once your t-stat starts to open, with a good (bigger is better here...)aluminum radiator the engine will get a big rush of cooler air and that will drop your engine inlet temps down and your fan may not even need to cycle most of the time unless it's extremely hot outside. The other tip I can suggest is wherever you draw your +12v (relay triggered) accessories from, make sure you route your alt. sense wire to that point also-your alternator will be able to quickly decipher the current load and adjust output accordingly. -Jabin