View Full Version : Warm engine - no crank
Ken Packard Jan 31st, 09, 01:03 PM I have a BB crate engine that turns over easy and starts nice when cold. Timing is set and engine runs well. When engine warms up to operating temp and I shut it off, when I attempt to start it again it will barely turn over. Again, it is a new crate engine with the gear reduction starter. Any ideas??
Thanks,
Ken P.
Everett#2390 Jan 31st, 09, 01:25 PM Disable the ignition and crank it. If it cranks, then retard timing.
If no cranking, then increase the size of cables, and place negative cable on the block.
I'm certain you have cleaned both ends of the battery cables and where they attach.
alanrw Jan 31st, 09, 01:57 PM Ev, if it turns over easy when cold, would that tend to remove intial timing as the culprit here?
alan
Everett#2390 Jan 31st, 09, 03:20 PM Ev, if it turns over easy when cold, would that tend to remove intial timing as the culprit here? alanI wouldn't think so, cold engine, loose tolerances.
My experiences have been a fail-to-crank hot engine has been excellent starting cold. Either too much initial timing, heat soaked starter, too small of cabling/battery, or improper shimmed starter-too close backlash when all is hot, starter solenoid engages, but no turn and come to find out, starter drive is jammed in place and cables/battery is smokin'.
Like I said, just my first hand experience. I'm open for discussion.
Ken Packard Feb 1st, 09, 12:22 AM Here are a few other factors about the set-up in this car - New engine has only been run in driveway, has less than 1hr running time at an idle or low RPMs, engine timing is set at GM reccomendation with vac adv not attached(32 degrees advance), Optima battery is located in trunk with 1 gage cables (pos and neg) running to engine with the neg grounded to the engine. Starter is new GM gear reduction starter that came with the engine. I just bolted on with no shimms. I tend to think timing is not the issue because the timing went well and the engine runs so smooth after it's warm with smooth rpm, increases with no hesitation.
You may have a point with the heat soaked starter of the starter drive tolerances when hot. I think that with #1 gage starter wire that would not be the problem. Also, I think I have an excellent ground. And lastly, the battery is the new heavy duty Optima red top battery. Could the battery not be receiving the proper return charge from the alternator?? I'll take another look on Sunday with any ideas anyone may have.
Thanks,
Ken
Pro-Street69Camaro468 Feb 1st, 09, 08:12 AM I had the same problem put a Tilton mini on no problem since.Posted same question one year ago.$300 starter not to cheap though....
Everett#2390 Feb 1st, 09, 10:07 AM With battery in the trunk, charging cable loss comes into play. Measure the BAT terminal at the alternator and compare the battery posts measurements - s/b less than 0.4 volts difference.
If you have an ext reg alt, use a Wells VR715 reg - electronic, or adjust the OE mech reg to correctly recharge the battery.
If you have an internal reg alt, you may have to move the 'sense' wire to the positive post so alt has a better reference to charge.
And same effect happens when attempting to start. Higher cable temperature, more current loss through the cable - given off as heat. A good measurement to make is to have one meter lead on the positive post and the other lead on the solenoid stud. This measurement will show how well current is conducting through the crimps, lugs, and cables. Yes, you will have to extend one meter lead to make the connection - add the extension and place the ends of the leads together and watch the meter, it will eventually zero itself, then make the measurement. Should be less than 0.5 volts loss for the connections.
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