Is engine cranking normally slowish?

Blrfl

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The fuel rails are pressurized by an electric pump before you thumb the starter.

--Mark
 

90210brandon

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What would happen if the brushes in the starter motor were worn or something like that? Would it be slow to turn over?
 
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What would happen if the brushes in the starter motor were worn or something like that? Would it be slow to turn over?
Usually no. You would have a lot of sparking at the brushes and eventually it would not turn over at all. Actually, the brushes are soft graphite and wear to make themselves shorter, so unless one fractured, it will still do its job until the carbon is gone and the spring touches the armature.
 
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The fuel rails are pressurized by an electric pump before you thumb the starter.

--Mark
I know that, but it takes a couple of seconds for that to complete. If you thumb the start button before the FI light goes off, the fuel rails may not be fully "charged".
 
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I'm not sure about the cranking slowly part of your reply, but I don't think my ST cranks slowly with a fully charged battery, just a little longer than the C10 did when cranking it up. I can't say for sure, but I don't think my ST usually cranks long enough to prime the engine with oil, likely just long enough to pressurize the fuel rails. That is obviously not an issue with carburized engines.
Well, my oil pressure light never comes on after the engine starts. Oil pumps make (enough) pressure almost immediately. I assume fuel pressure is up when the FI light goes out, maybe before, but I usually wait until it goes out before hitting the start button.
I don't know what the actual cranking rpm is (or should be) on the ST. It certainly sounds slower than what I am accustomed to, but have no data to base that on other than what I hear/have heard. Battery is good. Cranks the "same" speed always and just takes a second or so of cranking to fire up. Not an issue, just a characteristic of design apparently in getting the ok from the various sensors.
But, the way the carb'ed Concours (both the 2002 and 2005) fired up was sort of amazing. Perhaps impressive is a better term.
 
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This afternoon,,, after disconnecting the tender,, I turned the dual 100/60 high beam switch to low beams,,, and the 50w x 2 driving lamps, and everything else that comes on with the ignition switch. And when I hit the starter,,, that little geared starter spun noticeably faster,,, pretty good actually,,, and my fairly new agm battery is nothing special. So it did actually fire up faster,,, simply because the engine was cranking faster. But I still estimate it took about number of rotations, to "light up",, so expect the ecm is really in control of the startup cycle. I will make a note to turn all these power suckers off and/or down when I park at days end. cheers,,, Cat'

I too have noticed that my ST13 Blue STar cranks more than I would have expected before lighting up. Obviously,, it is a much geared starter. But after putting in a new battery,, it did not crank faster,, either hot or cold. No big prob,, I just decided that's the way it is,,, and might be attributable to the function of the FI system. One other thing I will take notice of, is if it catches any faster after installing a new set of iridium plugs. Cat'
 
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