Conor wrote: ↑Wed Aug 05, 2020 1:55 pm
TomPierce wrote: ↑Wed Aug 05, 2020 1:42 pm
Conor wrote: ↑Wed Aug 05, 2020 1:26 pm
Citation needed. I will mention, my high school car which was brand new (yes, I was a spoiled), had the manual transmission replaced twice. Ironically, I drive older automatic transmissions than my high school vehicle and there isn't even a hint of issue with the auto transmissions. One has 290k miles on it and I am planning an engine rebuild this winter, but I'm not planning to rebuild the tranny.
If you wanted to say simpler, I could buy that. There are no electrical signals (other than maybe speed sensors), shift kits etc on a manual transmission, but simplicity doesn't always equate reliability.
What if your battery is dead because your alternator went out? Do you carry around a spare alternator just in case?
I've been driving longer than many on this site have been alive, I haven't run into that situation. But possible I suppose.
But it raises an interesting issue for car geeks like me (I'm restoring a '62 Austin Healey with a stick, I used to work in a garage before college, etc). Popping the clutch spins the flywheel which in turn provides the compression to start the car, bypassing the starter. I'm honestly not sure if a dead alternator would prevent ignition; the battery won't charge, for sure, but the spark for ignition is from the ignition coil, right? Honestly not sure about your problem, I'll look into that.
-Tom
Most car ignition systems are dependent on the electrical system having some life. Coil packs (which run of a control module to distribute the timing of spark) are dependent on the electrical system being alive and well. A distributor (mechanically driven by the engine) also needs the electrical system. Airplane piston 100LL engines utilize magnetos which are "Self contained" and serve as their own electrical source and spark distribution (also, most airplanes have 2 magnetos and redundant spark plugs - 2 per cylinder). An airplane with magnetos can then have complete failure of the electrical system without affecting the engine ignition system.
In other words, if disconnect the ground from a car it won't run - manual or automatic. Alternators die (I replaced my wife's toyota alternator about 18 months ago). A manual transmission won't save you in that case once the alternator dies and the battery gets worn down to a nub.
EDIT: removing the ground from the battery will render most electrical systems useless. It was used as an example of how an engine can't run without it's electrical system.
Hmm...there's a lot to unpack in there, Conor.
Yep, disconnecting the ground cable will render the system useless, although if you want to start a car by popping the clutch I'm not sure why you'd do that. Popping the clutch is a work-around when the electrical system
isn't "alive and well," the battery can be completely dead, not even a click from the starter, nada. I've done it probably two dozen times? And driven lots of miles after ignition. But to your posed issue, I researched it and while you can pop the clutch and get ignition, if there is a totally dead alternator/generator, you're only going to have power for a spark based on whatever residual power is left in the battery, which could be close to nil, i.e. a few blocks of driving. Having said all that, and having replaced hundreds of batteries (a long, long time ago) I'd say the ratio of just-worn-out batteries vs. those caused by bad alternators is probably greater than 50:1. Total guess on that. I also recall that testing the alternator with a voltmeter always showed
low voltage, not
no voltage (and excess voltage indicated a bad voltage regulator). So your hypothetical is valid, but maybe a bit (or a lotta bit?) remote in likelihood.
I was curious about this, all of my pop starts have been with older cars with generators, not alternators.
OK, I'll give the Bronco-philes their thread back.
-Tom
