voltage drain

[2Twisted]

I seem to have a voltage drain at high rpm.  I am running a one wire 110 amp alternator on a small block chevy.  It seems to drain my new optima battery.  Any ideas?

[Chevy Racer]

Are you sure the alt is charging? I would charge the battery 100% and have it load tested hot and again when its cold.  Sounds like a battery issue to me pending the alt is working right.

[Jthomas]

Run a bigger power wire to the batt.

I run 3 1000 amp batts on a 300amp dc power alt. I run multiple strands of 0 gauge from the alt to the batts.  

But that's weird that ur loosing power at high rpms. You should be putting out more. It's possible that your power wire from your alt to batt isn't connected well? So as you turn more rpms and use more power, your batt alone can't keep up with the power draw?

Or when you installed your alt, you may have grounded it out with a wrench or anything during the install? That will cook the diodes in a heartbeat.

[2Twisted]

It is a brand new Optima blue top.  There is no factory wiring, it is all new automotive wiring crimped and shrink tubed. All connections are tight.  AT idle and lower rpm's volt meter is reading 14 volts indicating the alternator is charging.  When I get wound up to 7000 it runs good for a minute or two then will stall.  When I restart guage is dropping to 10 volts and battery is weak.  The battery was off a fresh charging in the shop and only has 4 Bogs on it.

[Jthomas]

What kind of ignition system are you using?

[betterbeaters]

what all are you running on it? fans, fuel pump, elec. water pump, msd,steering pump?

[2Twisted]

Ignition is just a drop in accel hei distributor brand new.  I am running an electric fan, fuel pump, ignition, and wipers.  Battery is brand new 1000cca optima marine blue top.

[2Twisted]

Battery has 130min reserve capacity.

[73chevytruck]

Don't sound like your alternator is charging. Start it up and dissconect your positive battery cable and see if it will stay running. If not. Its not charging.

[old school truck dude]

You can also see roughly how its charging by holding a wrench against the back of the alt right in the center where the back part of the armature is, being VERY careful to not touch the positive terminal, it should have a very strong magnetic pull at any rpm.. You should also be able to actually hear it charging, makes a "whirring" kind of sound.. This is most likely the alternator given what youve said about all the other stuff


Question: Are you runnin ANY OTHER THING on the same circuit as your HEI ignition system?? That WILL kill the motor usually. Ignition circuit needs to be all by itself for the best fire

[2Twisted]

Ignition is on its own fused circuit. 

[old school truck dude]

Ignition is on its own fused circuit. 

Alternator, provided all wiring is in good shape, thats my long distance guess

[Jjay78]

alt isn't working right man, or your wireing from your alt to your batt is to small

[Eroq]

alt prolly cutting out at high rpm.. does it on my 01 sonoma anything higher than 4000rpm.. it cuts out and lights dim..

  get a higher quality alternator

[ToughBowtieTruck]

Don't sound like your alternator is charging. Start it up and dissconect your positive battery cable and see if it will stay running. If not. Its not charging.

That test isn't that great. The battery is the "resistor" of the system, and the alternator uses it to relate how much charge to put out. Unhooking the battery results in a "no resistance" condition, so the alternator defaults to full charge capacity.

So, it may stay running, but that doesn't mean the diode trio and all that is good in the alternator . . .