electric issue

[gjp]

I have asked this a few times and got some info but I am at a loss and need ideas....
My truck has a voltage problem. Voltage drops, idle drops and WBO2 goes up a few points. When its ideling at 12.4 it jumps to 14-15. Stil runs but the idle drops to 600. I can see the volt guage dip about 1/4 inch from above to below the line. with the truck at idle at 14.7 it junps to 18-19 and the truck dies. The Dm show the voltage from 13.8 and it drops to 11.4ish. I have a remote battery. The battery is new, so is the 140 amp alt. I have a #2 wire going from the lowe manifold bolt to the frame. The remote battery has #2 going from the battery to the frame. Both points on the frame have just been sanded and tightened down. The battery has a #1 wire from the battery to a post where the old battery was. Then off to the starter,alt....like stock. voltage drop is worse when hot sometimes its not as bad. The new battery is holding 13.5 volts? weird to think the voltage would drop with the batter still at high voltage. I bought some new battery terminals to see if those are bad. What else could I try. I do have a UD pully on the crank. But again would not the battery compensate for the voltage drop if its the alt?

 

[WyoSyclone]

Re: electric issue

Hi Gary,

My thoughts..

1. If the underdrive pulley isn't allowing the alternator to basically 'turn on', you are running on battery power, which will always be at 12.2 volts at best, then will get lower as the vehicle runs off the battery.

2. If the WB isn't seeing enough voltage (Sy running off battery) it will start producing inaccurate WB output, altering your AFR.

3. When your idle drops to 600 RPM the alternator really has no chance of outputting voltage due to the UD pulley.

4. The battery can't compensate for the voltage drop.. it is a storage device that can only store at 12 volts, it can't 'make' any voltage higher than 12.

I would put the stock pulley back on.... I bet your problems disappear.

Anyone here chime in if I'm wrong on this... but, get a set of jumper cables and hook the Sy up to another car. Start the other car, then start the Sy. If your alternator is not producing output, your Sy will start running off the other car's alternator, because it is sitting at a higher voltage potential. If all of your problems are gone, you can be assured your problems are being caused by a bad regulator, or the alternator just not spinning fast enough.

Hope this helps!

 

[gjp]

Re: electric issue

I hooked my truck up to another battery before. But not to another car. i will try that. Thanks Rob.
My truck came that way with the UD pulley. I did not know untill I went to change the belt. I cant find a stock one. Makes sense because if I drive it on the freeway it will idle fine for a little while then start acting funny again.

 

[autoaddictions]

Re: electric issue

Gary whare are the 2 ground ring terminals grounded too. Im speaking of the 2 in the same harness as the alt. wires. If there grounded to the intake bolts or the cast alt. bracket(you powder coated yours) this could be your problem. Try grounding to the front of the drivers cylinder head. Also you may want to run a larger charge wire from your alt. to the battery directly, 4ga should do. The factory wire is only 12ga and only had to travel 3 feet to get to the battery. Now your traveling 12ft or more and using electric fans that realy eat up amps. When your at 700 rpm or less theres just to much load for what your charging system can supply. Re ground those wires and run a temp. 4ga from the back of your alt. charge bolt right to the battery. Then try it again. I saw a 2 volt increase buy doing this and i was fine untill i added the electric fans. This fixed it for me.

Oh yea im also using underdrive pullys!!

 

[Syclone#892]

Re: electric issue

I recommend doing a search for a post from Ed Hess. He went through I believe a similar situation and he had a chart to go through so you could find the cause of the problem. Good Luck

 

[gjp]

Re: electric issue

I did see that post. I think I have read everything on here at one point in the last year.

 

[TYTILIDIE]

Re: electric issue

Im with the under drive pully idea. Has it always had this problem? If not and you got your truck with the UD pulley, then thats not it. Not sure if you saw my outcome of the same problem but it ended up being the voltage reg plug. The wire was toast but the insulation looked great. I swear I would have never know if I didnt push the wire in and out while hte truck was running.

 

[gjp]

Re: electric issue

It used to have a slight miss. at idle sometimes. never found out what it was. thats why I did the top end rebuild and replaced everything. problem is worse now. I will replace everywhire connector in the engine bay.

 

[SY2455]

Re: electric issue

It used to have a slight miss. at idle sometimes. never found out what it was. thats why I did the top end rebuild and replaced everything. problem is worse now. I will replace everywhire connector in the engine bay.

That slight miss at idle may have been the stock Syclone chip, mine did that after a full tune up trying to get rid of it. 99% of it went away after I installed a MSD-6A

 

[Daryl H]

Re: electric issue

I ended up putting the smallest alternator pulley on to overdrive at idle.
The alternator would not be excited enough in order to output voltage/current.

 

[cloneman315]

Re: electric issue

i did the same with my alt overdrove it at idle and keep my underdrive pulley on the crank

 

[Tooky]

Re: electric issue

My truck also came with an underdrive pulley and no stocker. A friend with a 1999 S-10 Xtreme "upgraded" to underdrive pulleys and gave me his stock pulley for free. I assume it was the same diameter as the Syclone stock one. Either way, it bolted on and has worked great for 5 years. If you really need a stock one, you could check with other S-10 owners running UD pulleys.