GM Truck Club Forum banner

1 - 20 of 20 Posts

·
Registered
Joined
·
324 Posts
Discussion Starter #1
i read somewhere that the 1 wire alt in my 94 suburban and be rewired to behave like a 3wire alt( balls to the walls charge on start up). is this true and in such case can someone please explain to me in both tech terms and like to a 5year old child.
 

·
Registered
Joined
·
1,218 Posts
i read somewhere that the 1 wire alt in my 94 suburban and be rewired to behave like a 3wire alt( balls to the walls charge on start up). is this true and in such case can someone please explain to me in both tech terms and like to a 5year old child.
Are you absolutely sure its a single wire alternator.....people often mistake a 3 wire for a single wire.

I would be amazed if it was a single wire as the 3 wire came out in the 70's. The single wire alternators were used for very limited applications(street rods, and use a specially excited regulator designed for industrial, farm and fleet usage) due to its disadvantages(warning lamps and dash lights wont operate). You have to wire a single wire to run dash lights etc...

My understanding if it does have a single wire the only advantage for a single wire is that its one wire for install...nothing to do with charging power etc... Personally I wouldnt change to a single wire for that truck.

Here is a 3 wire alt...

Alternator.jpg Alternator2.jpg
 

Attachments

·
Registered
Joined
·
324 Posts
Discussion Starter #3 (Edited)
looks like 1 wire to me. i do not want to change to a single wire, thats what i have. i want to change to a 3 wire. are you attempting to say that this truck is not supposed to have a single wire to begin with? never the less im hoping that someone knows how to switch to a 3 wire and could possibly explain what to do.
 

Attachments

·
Registered
Joined
·
1,218 Posts
looks like 1 wire to me. i do not want to change to a single wire, thats what i have. i want to change to a 3 wire. are you attempting to say that this truck is not supposed to have a single wire to begin with? never the less im hoping that someone knows how to switch to a 3 wire and could possibly explain what to do.
Ahh..I got confused while I was typing away!

My guess this a 3 wire alt even tho you only see that one wire in the harness. If I am not mistaken if it were a one wire you wouldnt have that connection with the black plug. You would only have a wire going from the alternator to the battery :) (one wire)
 

·
Registered
Joined
·
1,218 Posts
Here is a one wire setup:(note the top where there is no plug) Are you having electrical issues?


IMG_2311.jpg
 

Attachments

·
Registered
Joined
·
324 Posts
Discussion Starter #6
in a sense yes. with so much as just turning on my headlights the voltage drops up to 1.5vdc. now with the extreme added audio i find myself having to run a battery charger about once a week to help the batteries catch up. i replaced the alt 2 times thinking that might be the problem but no such luck. its almost like the so called 105amp alt is only charging around 30-40amps. my t-bird to has only a 105amp alt and with the audio system at full power and headlights on the light wouldnt even dim, the lowest voltage was 12.9vdc and that was with everything running and an underdrive pulley on the alt. so due to such im certain that something is wrong and was thinking along the lines that for some reason the alt is not being allowed to get to full charging power.
 

·
Registered
Joined
·
324 Posts
Discussion Starter #7
well i decided this week to fix the problem im going to add another alt and leave the wiring as is. after looking at the stocks mounts i believe i can mount 2 alternators with 1 bolt from each to the stock flatform and fab a t-fitting to connected the 2 alts in the middle. sorry got a 5year kicking my ars as im trying to type this so i cant think very well on how to explain what it is i plan to do. ill post pics once im done.
 

·
Super Moderator
Joined
·
3,377 Posts
Sorry mudpuppy, but if you're getting that much voltage drop just turning on your lights, you have electrical issues somewhere you need to deal with. Adding a second alt may mask the problem, but that's not a fix, it's just masking the true issue.

How did you figure out the alt's only putting out 30-40 amps? Through a test on an alt testing setup, or through some other means?
 

·
Registered
Joined
·
1,218 Posts
X2...have you checked the "Big 3"?

From another site:

Definition: the "Big Three" upgrade means improving the current capacity of three cables: 1) alternator positive to battery positive, 2) battery negative to chassis, and 3) engine ground to chassis. Some people replace the factory wiring; others add additional cables to the factory wiring. This instruction is to add cables to existing OEM wiring.
Parts and Tools:
As a minimum, you will need to purchase the following:
• Sufficient length of high-strand count high capacity power cable.
- The length required differs for every vehicle. You can measure the length of the existing cables and buy the same length, or contact your dealer or a mechanic and ask, or sometimes you can look it up in a manufacturer's wiring book, or guess. If you guess, make sure you over-estimate and buy too much.
- High strand count cable is more flexible and more reliable than low-strand count cable. Never use solid-core wire in a moving vehicle as it will eventually break.
- The gauge of wire you need depends on the total current draw of your audio system, and/or the current generating capacity of your alternator. Never use smaller cable that you used to power your amps; never use smaller cable than what already exists in your vehicle; never use smaller cable than the generating capacity of your alternator; never use smaller than 4 AWG (it's just not worth the time to use anything smaller); if in doubt, always use higher gauge cable than you think you need. If you look at the Power and Ground charts and your amplifier current draw corresponds to 2 AWG cable, use no smaller than 2 AWG cable, and use 1/0 if you can.
• 6 ring terminals or lugs of the appropriate size for the cable chosen. Two of these need to be large enough to fit over your battery posts, or appropriately sized to bolt onto your existing battery terminals.
• 1/2" or 5/8" shrink tubing (or some other form of permanent electrical insulation. Tape is NOT recommended.)
• Cable ties (plastic zip ties.)
• Wire cutters large enough to handle the cable you choose.
• Crimpers large enough to handle the connectors you choose.
• Soldering iron or gun.
• Solder.
• Scotch brite and/or a small wire brush.
• Heat gun.
• Safety razor blade (or other tool for stripping cable).
• Heat gun (if using shrink tubing).
• Wrenches for removing bolts in your vehicle.
Procedure:
1. Make sure your engine is completely cool before beginning. Identify the three cables being replaced. Make sure you can reach both ends of all cables. NOTE: the engine block to chassis cable may be between the engine and the transmission, or connected to the transmission and the fire wall, and is often an un-insulated flat braid cable.
2. Determine the lengths of cable needed to reach between the three locations being upgraded. Be sure you measure with a flexible tape (a tape measure used for sewing works great) and record the total length along the path you intend to install the cable. You do not want your cables to be pulled tight between any two locations as things move and vibrate as you drive. Be sure to include at least 1 inch extra for slack. NOTE: there is no reason to copy the existing wiring layout in your vehicle unless you want to. Also, be sure that the path you choose does not follow or lay across anything that gets hot, like exhaust parts, or anything that must move, like throttle linkage.
3. Cut your new cable to the three proper lengths. NOTE: some people like to use red cable for positive and black cable for negative. Doing this is completely up to you and is nice, but not necessary. You can use cable with any color insulation you like.
4. Strip each end of all cables to the proper length for the terminal lugs being used. NOTE: after full insertion into the lug, a small "band" of bare wire is usually seen between the back of the lug and the beginning of the cable insulation.
5. Begin at any one end and insert the stripped cable into the lug. Make sure it is fully inserted. Crimp the connector to hold the wire in place. NOTE: crimping large cable can be difficult. The intention here is not to make the crimp the sole means of holding the wire, but only to make sure the lug does not slip around during the soldering phase. I do NOT recommend using hammers or pliers or vices to crimp the connector as over-crimping can break the strands of the cable, reducing the current carrying capacity. Do not over-crimp.
6. You may need to use a vise or some other set of "helping hands" to hold the cable while you solder it. Heat your soldering iron and place it on the connector (on the lug side) barrel. Hold a piece of solder against the tip of the iron and melt the solder into the strands of the cable. Use sufficient solder to fill the connector and completely cover all strands of the cable. NOTE: the lug will get hot and will burn you if you try to hold it. Also, if the insulation on the cable starts to melt, you are over-heating the cable and not paying attention to melting the solder into the cable. You do not need to try and melt the cable!
7. Repeat the above steps on each end of all three cables.
8. After the cables have completely cooled, cut a piece of shrink tubing long enough to cover the soldered barrel end of the lugs and reach about 1/2" onto the insulation of each cable end. Slide this over each lug and use a heat gun to recover the tubing in place.
9. Disconnect your battery, starting with the negative cable first then the positive cable. Discharge any caps you may have in the system.
10. Begin adding your new cables along side the existing ones. I usually begin with the alternator positive cable. Locate the output stud on your alternator and remove the nut. Slip the new cable onto the lug and replace the nut. There is no need to disturb the existing cabling. Route the new cable to the battery and position it to connect to the positive battery post (or connect it to the positive terminal on the OEM wiring) but do not connect the battery yet.
11. Secure the new cable in place by using cable ties every 6 to 8 inches. Secure the cable to cool non-moving parts!
12. Locate where the negative battery cable attaches to the vehicle chassis. Remove this bolt and the OEM battery cable, and clean the mounting area of the chassis using scotch brite and/or a wire brush. Make sure there is no dirt, rust, paint, undercoating, etc in this location. You want bright shiny metal. Connect both your new ground and the OEM ground back to the chassis. NOTE: Some people like to create a new ground location by drilling into the chassis and using a bolt with star lock washers for the new ground cable. Route this new cable back to the battery and position it to be attached, or connect it to the negative terminal. Do not reconnect the battery yet.
13. Secure the negative cable using cable ties every 6-8 inches. Again, don't tie it to anything that moves or that gets hot!
14. Disconnect the engine ground strap at both ends. Using the wire brush or scotch brite, clean both the engine block and the chassis as you did for the first ground strap.
15. Line up the lugs on both the OEM ground strap and your new ground cable, and use cable ties to secure them to each other. This is much easier to accomplish in your lap or on the floor than it is while lying under your car or hanging upside down in the engine compartment. Reinstall both cables at the same time using the factory bolts.
16. Double check to make sure all bolts are tight. Be careful not to over-tighten them as you don't want to strip anything! Also, on some factory alternators it is WAY too easy to twist off the positive output lug. If you break it off, well hell, you really wanted a high-output alternator anyway, right? It is also a good idea at this point to measure resistance of the new cables. Take an ohm reading between the battery end of the new ground cable and the engine block. It should read less than one ohm. Also check between the alternator bolt and the disconnected positive battery terminal, which should also be less than one ohm. If you read too high resistance, double check all connections and make sure you do not have something c**ked sideways or hanging loose.
NOTE: Realize that the "absolute ground" of the electrical system is not the battery negative terminal or the vehicle chassis, but is the case of the alternator itself. This is why perhaps the most important cable among the Big 3 is the engine ground strap, as this is what connects the alternator ground to the vehicle's chassis. Be certain the resistance between the alternator case (the engine block assuming the alternator is properly bolted to the engine) and the battery negative is minimized. (Thanks to the12volt for pointing this out!)
17. When you are sure you are done and anything in your system that you may have disconnected are re-connected, clean your battery posts and reconnect the positive battery terminal first, then the negative one.
18. Start your vehicle. Hopefully the engine starts. :) Examine the engine compartment and make sure none of your cables are getting hot or are vibrating or shaking around. If they are vibrating too much you may need to relocate them or use more cable ties. If you see smoke, immediately shut off the car and disconnect the battery. Seek help. :)
19. Assuming all looks good, take a voltage reading at your amplifier and ensure you read 13.8 (or higher) volts. This indicates a properly operating charging system.
20. Now'd be a good time to turn it on and make sure it sounds good! Then of course log onto the12volt.com and post that you have upgraded your Big 3!

---------- Post added at 07:16 PM ---------- Previous post was at 07:10 PM ----------

And what "exteme" audio are you running? Most people dont "need" 2 batteries or alternators for that matter.
 

·
Super Moderator
Joined
·
3,377 Posts

·
Registered
Joined
·
1,218 Posts
He is running tons of audio equipment in the truck, enough to blow out his eardrums. Once he gets this voltage drop issue sorted out, he probably could use a pair of high-output alternators, but first things first.

http://www.gmtruckclub.com/forum/f17601/been-busy-71104/
That doesn't tell me sqwat....


I have 2 amps and 2 12"subs that wil make you deaf,blurred vision,make your chest hurt,and induce labor if your pregnant.
 

·
Registered
Joined
·
324 Posts
Discussion Starter #12
currently im drawing 720watts when all of my lights are on. so ok the lights got away from me and maybe this poor lil alt is doing everything it can.

the sound system currently has 3 AQsdc2.0 12's with the hdc3 12 otw. it should be here by thursday. im currently at 149db and my objective is to hit 154+db.
i believe im going to add a power masters 200amp off set wired parallel with the oem alt. the wire from the alt to 3batts has been upgraded along time ago to 0gauge. i found a site the other night that offers 00gauge. i think im going to get some of that and also maybe add another 3000amp batt.

my 149db is at a voltage drop to 11.5vdc. if i can maintain atleast 13vdc or higher that in itself might put me to 150db. im also going to have to upgrade my mids very soon. with 6 6.5's and 2 5 1/4's its getting hard to here them all over the bass. that will most likely also then require more amps needing more power so the new bracket for duel alts im actually going to make it for 3 alts. im pretty sure later on ill be adding another 1.

for those that followed my other thread, the barn door window repair is still holding up. im starting to worry about the back side windows though.
 

·
Super Moderator
Joined
·
3,377 Posts

·
Registered
Joined
·
1,218 Posts
Once you get in the 154db range most people don't care of you can hear the highs as you are strictly competing for spl. You may want to have seperate batteries for your amps with a high output alt.

There is a guy in phoenix with MECA who hit 153 I believe with a single zapco 12"sub. He has the record for the loudest single 12 also.ou

I had never competed spl credit but when I got my 7th order blow through I tried out to see what it would hit..i got 147db but with better music choice and some tuning the amp I could probably get in the 150s.
 

·
Registered
Joined
·
324 Posts
Discussion Starter #15
Once you get in the 154db range most people don't care of you can hear the highs as you are strictly competing for spl. You may want to have seperate batteries for your amps with a high output alt.

There is a guy in phoenix with MECA who hit 153 I believe with a single zapco 12"sub. He has the record for the loudest single 12 also.ou

I had never competed spl credit but when I got my 7th order blow through I tried out to see what it would hit..i got 147db but with better music choice and some tuning the amp I could probably get in the 150s.
after some of the stuff that i have been starting to see i can easily believe that. without question if you stay away from the audio stores and look more for the little guys making there own off brands then you can exceed what any audio store brainwasher will admit is possible.

as for the alt system i was looking at this to much from inside the box. i did alot of research since my last reply and i have figured a perfect solution. the wire plugging into the alt is a straight through batt single wire. depending on the current delivered it tell the voltage regulator what level of charge to allow to pass by. the intent which works very well by design is to protect the alt from burning up at lower rpm.
on average (not the same for all but close) the alt will charge at full amperage between 11.9-13.6vdc. once it goes over 13.6vdc the regulator start dropping off to prevent overcharging. once it goes below 11.9 it drops off to prevent burnout until proper voltage it recovered which usually would happen as the engine turns up in rpm. now the cure to my problem is far simpler than what i was thinking. alt1 will have a 40%od pulley tricking the alt into thinking that it is spun up. alt2 will have a stock pulley. with the 2 currents parallel to the batt there is little to no chance of dropping the voltage below 11.9vdc by what my system current draw requires. the be on the safe side the 40%od on alt1 will help ensure 11.9 or higher voltage. now yes this does increase the chance of alt burnout at idle but yet most of the time im OTM to avoid 5O detection. this is also factoring in 3 batteries that i have hooked up to. the higher amp rating alows for more of a burst reserve of current allowing the alternators to be more efficient. currently my batt system amp rating all combined is 2600amps. 2 yellow tops and 1 red top under the hood. the yellow tops are great for there location being mounted in the back with the amps and subs. the red top is going to be replaced with a high amp 3000amp batt. thus leaving me with a 4800amp batt system( keeping in mind this is not actual numbers since all batteries have different aspects of power storage and certain power losses are not factored in for current travel leak off).
 

·
Super Moderator
Joined
·
3,377 Posts
I'm not sure your plan is going to work right. Logic and experience says that the alternators need to be matched in their output. The reason behind this is if 1 alternator is putting out more power, it will backfeed that power back into the alternator that's putting out less power. The result? At least 1 burnt out alternator. This follows the same logic behind matching batteries in amps and type.
 

·
Registered
Joined
·
1,218 Posts
I think if you have a high output alt running separate batteries in parallel you will be fine. Maybe use a battery isolater if you want.

Do a search on google for "battery bank"...should get lots of ideas and how to's.
 

·
Registered
Joined
·
324 Posts
Discussion Starter #18 (Edited)
ok both alts have been hooked up for some time now. 1 has a 40% od pulley on it and the other stock. no this will not hurt the alternators being at different outputs since they are both the same voltage, and no it wont hurt the batteries. with both at idle im now getting an average of 130amps for charging. at 1500rpm im getting 215 charging amps(keeping in mind this is not a constant, the alternator does modulate the amperage as needed). with both alts working together in parallel the voltage has never dropped below 13vdc. it maintains an average of 14.7 with the sound system off and an average of 13.5vdc with the system on at full tilt. no more dimming lights, slowed fans or blowers, speedo jumps, engine burps, nothing showing any signs of lack there of charge.

it was very easy and basic to rig in the 2nd alt after looking at it for about a week. anyone with a welder and chop off saw and some scrap metal can do this. ill post pics soon. whats best is the way i did it im still using the very stock belt that was also used for just 1 alternator. i didnt have to remove any components, just the idler pulley and installed a smaller pulley on the tensioner arm. from looking at it i might be able to stuff 1 more alt if needed later on. ill cross that road when the time comes.
 

·
Registered
Joined
·
1,218 Posts
Sounds like you got her whipped....how do you like the audioque subs? Post up some pictures of the alternators and system if you get a chance.
 

·
Registered
Joined
·
324 Posts
Discussion Starter #20
the subs are great. with double hearing protection on they still made my eyes water. the local audioshops worship it. however im changing up the system a lil. currently its running just 3 aq sdc2.0 12's. well im replacing these with the AQ hdc3 12's(3inch duel coils, 1ohm each, 3inches of cone movement, 2000watts per speaker) and then using 1 sdc2.0 12 up front for show. the other 2 2.0 12's will go into the gf's car. currently working on a deal for a 5k rms prototype amp from a custom amp shop. the manufactures didnt want such a beafcake amp so they had to down scale it for mass production. leaving them with 22 proto's and yeppers i get to get one. the lab even told me do not run it at full tilt for more than 20min no matter what charging system you have or it could fry your alts and batts. this thing takes 2 0gauge wires for power and 2 0gauge wires for ground. the lab claims at full tilt it will consume up to 342amps at 12.7vdc. thats more than my entire system total amp draw.

i would rather wait until its finished for the pics unless you guys are interested in its current progress then np. i can snap a few pics.
 
1 - 20 of 20 Posts
Top