Deactivating Alternator Field wire

[johnmyster]

Electrical concerns aside, fuel pumps are heat-sinked by a rather large quantity of sloshing fuel. Can't see a slight increase in heat produced making them much hotter. They fail when people run them dry - that's when they get hot.

The increase in resistive heat assumes an increase in current, which highes on a substantial decrease of inductive back emf. That is true for the case where shaft speed is reduced through application of a load - thus deflecting shaft speed from the free speed. In our case, simply decreasing the voltage (which by nature lowers the free speed of the motor, as well as the speed under load) at the SAME load does not produce the same effect.

Again, what if you were to use a 14 volt battery system rather than a 12 volt system? I just don't think a battery charger (or a power inverter) is going to be able to keep your primary charged when considering the loads of the vehicle.

[dcb]

What evidence do any of you have that the systems weren't designed to operate at a reduced battery voltage? Alternator belts break and cars still run for a time, engineers know this. Sometimes alternators just stop working altogether and you don't know till you have a dead battery.

I think the "low voltage fear so go buy an inverter and two chargers and an extra deep cycle battery and lug them around" plan should be rethunk.

[johnmyster]

Originally Posted by dcb

What evidence do any of you have that the systems weren't designed to operate at a reduced battery voltage? Alternator belts break and cars still run for a time, engineers know this...

I'm with you there, but just supposing that there's a reason why everything operates at 13.5 normally.

I'd rather not test out how a SRS system works at 9 volts. However, in the case of airbag systems, they're designed to work in a compromised situation (a crash) so I'd think they could do the job.

Lights would be dimmer. Windows slower. My power locks already struggle when cold. A 14 volt battery system would be a nice way to avoid these things.

[metromizer]

No trying to discourage anyone from scrounging parts, but sometimes being able to order what you need is the way to go. There's a lot of battery options availble thru automotive performance catalogs, including 16v batteries, chargers, step down transformers, isolation switches, sealed battery boxes and battery relocation kits and charging lugs. Check out the battery disconect switch for $16, every dragrace car with a relocated battery is required to have one, so the cost has come down. These catalogs are a good place to steal ideas to suit your own ecomodder or other needs. As someone else mentioned, West Marie is a great source of all-weather 12v electrical items, I've used many of their electrical products on race cars and trailers, very superior reliability compared to the absolute junk sold at the chain auto parts stores.

Powermaster 16V Battery Accessories - JEGS

and

Powermaster XS Power Batteries - JEGS