Converting 24volt to 12 volt M1009 CUCV

[Westech]

Ok Doghead, I'll stop now. Sorry if I seemed confrontational.

Sorry NMC_EXP, I'll stop.

Love Westy

 

[westechs_wifey]

Boy that does not sound like Westy..... maybe the Anger mgn classes are working.

 

[Bikermichael253]

Yup, that is what he was referring to. I'm going to be the devil's advocate here and ask why you want to convert it to straight 12V? You have the unique ability to run both 12V and 24V stuff, a far superior voltage for demanding starts. What is there to gain in this for you? If you don't understand the 24V and are scrapping it for that, pull up a seat and discuss it's merits. It can be converted fairly easy and if you do it right, converted back about the same. As far as reversing the poliarity, I'd not do that. The magic smoke could come out of some components. You would have to move the batts from series to parallel wiring.

Oh, welcome to Steel Soldiers.

Yes; I am also new to this forum. I bought a Banks Sidewinder turbo to install on my CUCV. Several mechanics recommended this specific brand and model for the 6.2. The problem is that the 2nd alternator mount conflicts with where the turbo physically mounts (forward end of new passenger side exhaust manifold). My CUCV really needs the turbo in the mountains where I live. I would love to keep the 24 volt system, but I can’t figure how to charge both batteries with one alternator. I had switched my starter two years ago to a gear reduction starter so cranking amps should not be a problem. If I feel that this turbo is the best option to make my CUCV more safe, more useful, and more fun to drive; I either convert to 12 volt or rig something to run the system off of one alternator. So what is the best suggestion that you would recommend.

 

[cucvrus]

I had switched my starter two years ago to a gear reduction starter so cranking amps should not be a problem.
How does this change the cranking amps? I am a bit confused. That would be a new lesson for me. 24 volts starters and 12 volt starters still require good amperage to work properly. Anyone? Happy Holidays.

 

[chevymike]

Higher voltage equals less amps.

Example, if a 12v starter needs 400 amps to start the engine, 24v would only need 200 amps. This is why the main starter cables are fairly small in size, as they don't need to carry as much current.

You can switch to a 12v starter but upgrade your main battery cables and the alt charge cables, to handle the extra current needs.

 

[cucvrus]

OK. I see that. But he is saying he switched to a gear reduction starter and that won't matter if it is direct drive or not. 24 volt or 12 volt. The direct drive and the gear reduction require the amps required of the 24 volt starter. Don't matter what drive it is. That was my point. So your example means a 6 volt GPW requires 800 amps?

 

[doghead]

• Power – Direct drive starters require up to 50 percent more electrical power to turn over the car’s engine than do gear reduction starters. This means direct drive requires more current from the car’s battery, larger battery cables are needed and other components are designed to handle higher current.
• Weight – Gear reduction starters are smaller and lighter than direct drive models. When replacing a direct drive starter with a gear reduction model, there is more space around it, which makes installation easier and may improve heat-resistance of the solenoid.
• Maintenance – Gear reduction starters have a higher part count, but internal wear is often less compared to direct drive starters since they use bearings versus the bushings common in direct drive starters. Misaligned or worn bushings are the most common cause of slow cranking of hot engines that use direct drive starters.
• Cost – Direct drive starters cost about 20 percent less than a comparable gear reduction model. However, "soft-start" gear reduction starters may require the additional cost of a magnetic switch installed in the solenoid circuit. The switch is required due to high current draw when the pinion gear initially engages the ring gear.
• Speed – In general, gear reduction starters turn more slowly at the flywheel end than direct drive models. However, because their torque is higher, they have a faster speed when pistons are at TDC on the compression stroke where it is needed most. This is why they are ideal for diesel or other high-compression engines.

 

[cucvrus]

In theory. But I still like a direct drive starter. It takes more abuse and lasts longer has been my experience. I was unaware of cost. But at the time the CUCV was made GM did not use gear reduction starters. That was always a Chrysler thing back in the day. Learn something new about cost. But still weak batteries and poorly maintained starting systems are the root of starting problems on all vehicles and engines. Maintain the entire system and you will have less starting issues. Thank you for the positive response.

 

[Bikermichael253]

I appreciate all of the input from everyone. Like one of the posts said; other than the starter, I have no need for any of the 24 volt system. I love my M1009, but it really needs the added power of this turbo. The Rosscommon modifications make great sense, but the instructions say to leave the #2 alternator so the #1 alternator could be removed. I need to modify their plan by moving #2 to the driver side (wiring and all). I can then follow the directions from the Rosscommon plan. On the schematics it shows #1 alternator charging only the forward battery and that alternator #2 charges both batteries. This is why I want to use the wiring from #2 alternator but physically mount it on the #1 bracket. I have bought a high torque gear reduction 12volt starter. GM built a few civilian K5 Blazers with the 6.2 , but they are pretty rare. The civilian Blazer used two batteries but only one alternator, so the entire electrical system in them was 12 volt only. People who actually need 24 volts should keep it; but that makes it almost impossible to boost acceleration or power. Converting to 12 volts is just copying the charging system from the civilian model.

 

[richingalveston]

if you are going twelve volt then keeping the 27si alt is not needed anymore. you only need it for the 24 volt alt. but since you need more power just change the drivers side alt to a new model like:

Mega Amp GM High Output Alternator

We have developed a high output alternator in a case that is smaller than the early GM 10SI case. The mounting on this alternator is exactly the same as the Delco 10SI, 12SI, and CS-130 cases or we have a 1 pivot ear that is common to AMC and marine use. It has the following benefits...

www.qualitypowerauto.com

This will solve your power problem. yes the banks kit will do wonders for the truck. I thought however the banks would still fit with both alts but I am probably wrong.
You could go extreme and do what I did to my 1009 but it takes some time and fab skills to make the elbow for the turbo. There is room for the exhaust to still go under the truck but I did not take that route.
The banks kit does make running the cross over a little difficult without hitting the axle. I am using the banks manifold but I changed the crossmember and motor mounts to the ORD parts and the exhaust crossover runs next to the oil pan above the cross member. The parts are not that much to purchase and it allows the cross over to not interfere with the axle or drive shafts.

If you could make the 24 volt system work. I would stay with it. Most of the new LED lights can use the 24volt input and then you can still use some of the military lights also.
I am still putting my roof rack together (work keeps getting in the way) but with my military 24volt IR lights and my $200 night vision video camera I can drive in the dark. (only off road, not used on the roads). Since my truck is not finished, I have tested it with my civy truck and you can see really good. Great for varmint hunting.