Proper crank time for auto start to avoid damage/dead-battery

Question

My '99 Grand Prix has an aftermarket remote-start. When the weather gets around 5°F like it is now, the engine does not start after 0.8 seconds of cranking. The system detects the car is not running after 30 seconds and tries again. If after the third attempt, the car isn't running, it gives up and my remote/fob beeps. Cranking without starting is obviously bad because it drains my battery when I perhaps need it most. The situation is made worse because the battery is less able to function at these temperatures. Thus I'm inclined not to reattempt remote-start too many times in fear of needing a jump. This has already happened once, although I have no way to prove the remote start being at fault.

I would simply increase the crank time, but I'm worried about when it's not that cold out, or when it's very cold out but the engine is already warm. In that case, the car starts almost instantly, so the remote-start would be cranking way longer than necessary. This gives that high-pitched whine or "whurr" sort of sound before it stops cranking.

Is that bad? Can I set the crank time to 1.5 or 2+ seconds, even when it may start after 0.2?
Remote-start is very important to me when it gets this cold.

Answer 1

I would not worry too much about whether you are going to run out of battery power, especially if you keep the remote-start at a .8 second crank time. You will not burn up enough battery juice to cause yourself any issues. Your battery has several identifiers associated with it. A common one is CCA or Cold Cranking Amps. This shows you what the power output your battery has when in a closed state (+ and - are connected to something ... in this case, your starter). There is another term which is called, reserve capacity minutes or reserve capacity for short. This explains how long a battery can maintain a certain amount of amperage for the number of minutes specified. For instance, my truck's battery is somewhere around a 75 minute capacity. Your car is probably around 60, unless you have a heavy duty one. If you are only cranking your engine for .8 seconds at a time, you are not burning into your reserve. Once the engine is started, it regenerates this power very quickly via the alternator.

This leads to your questions. Is it bad for your to over run your starter? I will say, it isn't good for your starter, but it shouldn't hurt it. Starters have a device located in the tip where the gear is located. It's called an overrunning sprag clutch. The sprag clutch has, by its definition, a one-way bearing in it, which allows it to spin freely in one direction, yet is locked in the other direction. It is there for just the reason you describe. If you engage your starter for longer than you should, the engine starts, and the sprag spins freely allowing the gear to spin without pushing the starter armature. The gear gets spun up a little bit, but the starter itself is not harmed. It's just an awful noise which comes out of it. Not the best thing to do, but is not going to cause it much issue.

As for setting the crank time, I'll give you my suggestion. Depending on how much you can fine tune the time, I would start bumping it up about .2 seconds at a time until you can get it to a point where it might not start on the first of the three tries it will do, but will by the second or third without fail. This would give you the minimal crank time with the best chance of success on the first set of start tries. If you move it up to 1.0 seconds and it still won't start on the first set, put it up to 1.2 seconds, and so on. If your granularity is only .5 second intervals, use that. If you find in the summer months you are hearing the auto start causing the overrun on the starter, bring the start time back down to the .8 seconds. I do not know how hard this is to change, but would bet since you are willing to do it this time, it shouldn't be too hard to accomplish.