Hey all:

My amp gauge drops almost to the red ( about 10 amps ) at idle when my bottle heater is on. Once I start moving it goes back up just past 13 amps It is the 860 heater and I am looking into adding another heater to get the pressure up faster with my 15lb bottle.

Is this normal or is it possible my alternator is starting to go. I just replaced the battery with a interstate battery and went with the MT-75 which has 650 cca compared to stock which is 525 cca.

If it is the alternator whold another stock one be ok or should I move up to a HO one? If so which one, how much and where can I purchase them.

Thanks

 

Mine does the same thing. The underdrive alternator pulley doesn't help either. I would like to see some responses to this also.

 

Mine does the same thing , but i have a different heater.

I also have an underdrive pulley

 

To make heat takes power -- lots of it.. That's normal, many people have killed their batteries warming the bottle in the staging lanes as well

 

I have two heaters and when they both are heating and the raid fan(s) come on, wow, the voltage drops a bit on gauge. That's with a new battery. Doing the same with my old battery it would drop to like 11volts, meaning alt was straining trying to recharge weak battery and run dual heaters and fan. Make sure you have a good battery. I went with the red top and now voltage drop is minimal. Once your car is started, everything runs off the alt, except when you have a marginal battery, then it also trys to keep it charged at same time. I also chose to use the NX heaters as they are 240 watters, compared to most that are 300watters for less strain on alt/batt. The 860 IIRC is rated in between the above wattages?
Robert